Category Archives: Oldsmobile Engine Stuff

Olds Oil Flow/Oil Restrictors

this is a referrence to the oil flow and the use of oil restrictors courtesy of Art at www.arrace.com . i didn’t see any need to elaborate on it. it’s well written and worth sharing.

 In the first pic, oil is pulled up by the oil pump through the oil pickup.  The oil pump pushes the oil through a passage in the #5 main cap and then through a horizontal passage approx .500″ to the oil filter adapter.  The oil is routed to the outer passages in the oil filter and forced through the oil filter element to the inner passage in the oil filter then back into the oil filter adapter and then back into the block through the large .500″ horizontal passage that you can clearly see on the rear of the block.  The oil makes a 90* turn up and then makes a 90* turn into the passenger side oil gallery.  (Note: There is also a .312″ diameter passage that continues straight from the large passage and then make a 90* turn to feed the #5 cam bearing.)  The oil flows forward to the front of the block in the passenger side oil gallery feeding the 8 passenger side lifters, mains #5, #4 ,#3 & #2  and cam bearings #5, #4, #3 & #2 along the way.
  olds_oil_rear

Once the oil reaches the front of the block it make a 90* turn down toward the main bearing.  Once the oil reaches this point it diverges into three different directions.  The #1 Main bearing,  The #1 cam bearing, and up to the driver side oil gallery.  The oil makes a 90* turn into the driver side gallery which feeds the driver side lifters.  (Note: The # 2, #3 & #4 do not feed into the drivers side gallery.  [i]See 3rd pic.
olds_oil

Restrictors are typically installed as shown in the diagram below.  The main restrictors as they are called restrict the oil going to the cam bearing journals ONLY.  This increases the oil to all other areas.  The ONLY restriction is to the cam bearing themselves.  Properly sized restrictors in this location can be used in any engine without fear of any damage.  Street, street strip, drag, circle track, off road & boat.  The cam bearings do not need all that oil and you can clearly see that by limiting the flow of oil to the cam bearing that the only other place it can go is to the mains on #1, #2, #3 & #4 and to the drivers side oil gallery.

Lifter bore restrictors should only be used with solid lifter or roller cams a then only if you know what you are doing.  Restricting oil here will limit the flow of oil to the top end including the lifters and rocker arms.  Care should be taken here as going too small can cause damage.
olds_oil_res

Some builders block lifter passages on the passenger side completely and tap into the drivers side gallery and feed all lifters from the same gallery leaving the other gallery to feed only the mains and cam bearing.  My 414 Olds is this way.  Pauls engine also has this setup.

Blocking filter bypass.  Drill & tap oil filter adapter for a 1/4″ NPT plug after removing the oil bypass assembly.  This prevents the oil from bypassing the filter element.  If you do this I recommend a GOOD filter such as a Sytem 1 and clean it often.

Proper size restrictors are available from [url=http://www.oldsperformanceproducts.com/products.asp?page=3&menulevel=Oil%20System%20Components&submenu=]Olds Performance Products [/url]and they can supply you with a proper tap as well.

Olds Engine 77-90

oct08055The picture to the left is a shining example of the 77-90 engine blocks for v-8 oldsmobile. this one here is a 403 olds engine that grenaded. in 1977 the block and cylinder head castings were re-designed AND re-issued across several gm factory lines. these engines were the 260, 307,350, 403, and the 350 diesel.similar to chevy small blocks, on the outside they were all pretty much identical. the base design of the block and heads remained as far as accesory’s, head and block dimensions as far as looks and how it bolts together, covers, oil pump, etc. with the exception of the diesel, pretty much older SBO heads and blocks will interchange most parts with the newer ones so you can mix and match.  the thing is that  all of these engines had in common is the amount of iron they put in em was reduced when it should have actually been increased- creating an even weaker platform. even though these engines were oldsmobile they to me are a completely different engine from the older generations. most of the casting designations are a large number followed by a letter(as i stated in another blog). i am going to address each of these engines separately and in a different manner as i was around these as a kid/teenager. as they are all an abortion unto themselves i will adress each of these individually..

When i was a kid, my dad got a used 82 cutlass station wagon with a 260 olds engine. it ran right for about a week and then for the next 3 years or so that he owned it, it was a nightmare. as a kid, it was the car that made me realize the power of a good mechanic- and the horror of being bullshitted by a bad mechanic. that car was an awesome solid car but was plagued with problems. we nicknamed it the copper bomb cause we always figured it would explode one day. it was a terribly under powered piece a shit, equipped with the half-assed q-jet carb and computer controlled HEI, it would simple never run right. to be honest you couldn’t see the engine as there were so many vacuum lines on the thing . my dad more than once threatened to reach under the hood and rip it all out like spaghetti! because it ran terrible from a poorly engineered engine management system, the engine carboned and loaded the engine full of sludge, plugged the intake and the oil return ports in the heads, bent push rods, rocker arms, overheated more than once. finally one day the tranny locked up at a stoplight and she went down the road. hind site 20/20, if you could have ripped the carb and dist off an older mid 70’s 350 ,it would have probably given the engine new life. but it those days it was the dawn of emissions/fuel management systems and unlike today, most mechanics outside of a dealership didn’t have a clue how they worked or how to work on em so they would throw parts at em and bullshit the customer over-and over-and over.  i hate to know how many times the old man got screwed on that car by an ill equipped mechanic. the engine simply never had enough power to ever put stress on the block. so in that reguard the lack of iron didn’t matter.

next would be the 307. now these believe it or not were a good engine. i, along with many friends, but nearly 200,000 miles on these engines without burning oil. now they had the same horseshit fuel management systems, but where the 260 was literally smothered by it the 307 survived, AND did not have enough power to stress the block. these were found in a lot of full size buicks and oldsmobiles from 1980-87, whereas chevy’s and pontiac’s got the 305 chevy. the 307 was not over powerful, but simply got the job done. the early 80’s 307’s were a bit sturdier in my books. from what i can gather sometime around 1984 they incorporated a swirl type combustion chamber for the cylinder heads and they really didn’t have the same longevity of the older 307’s. a 307 has windowed mains so if you want to put any kind of performance parts into a 307 block a girdle is the best place to start. i do believe that a 307 has a stock class speed record in nhra somewhere in the 12’s but i am not sure. don’t really give a shit to be honest.

next is the 350 gas engines from 77-newer. basically the same engine as the older 350’s but the main webbing was cast so thin there were windows in the casting above the crank: leaving only 3 small pieces of cast to hold the crank in on each journal. i am not sure what moron had the idea to do this, but in a stock application it would live because they put it in cars with a 260 rear axle gear so it was damn near impossible to stress the engine. of course like the 307, if you want to build it-start with a girdle. the cylinder heads were also a thinner smog casting different from the earlier ones. easily identified with an “A” after the number designation on the lower left corner of the head. i personally shit can these engines when i find em as the older 350 olds engines can still be had reasonable and it make perfect sense to go that route.

then there is the 403. my 77 olds 98 was originally equipped with a 403. these things were in full size cars from 77-79 primarily with a 2.63 rear axle gear and a th400. they were basically a 350 block with an ungodly huge bore and of course the windowed main webbing on the block. they also put these in the trans am’s in the late 70’s using a conversion bracket and a chevy motor mount. it’s kind of funny if you ordered a trans am with an automatic you got an olds 403; if you wanted a 4 speed you got a 400 pontiac engine. it’s because the bottom of the block was weak from the get go and GM knew it if you ask me. as with the car i had, usually even when driven by an old lady these things went to shit and were scrapped many years ago. BUT, the wild thing about the 403 is it retained the largest standard cylinder bore produced  from the factory at 4.35, yet retained the 350 stroke crank. so the potential for big horsepower is there, and many people have tempted fate. some did it successfully, and others like in the picture at the top weren’t so fortunate. if you really want to see and know about some wild 403 olds stuff seek out my friend Jim at www.jsmachineoldsmobile.com . there are others in the country that get into hardcore olds engines, but i think he is pretty straight up and seems to know his shit if you ask me.

and last but not least is the dreaded 350 oldsmobile diesel engines.after the fuel crisis of the 70’s, there was a call for mileage and the 350 diesel came about…touting 30mpg it was a sales pitch for the cars gm produced in the late 70’s. it was a half assed engineering feat if you ask me. it was basically a gas engine with a steel crank, flat cylinder heads, and a roosa-master injection pump atop the front to inject fuel. these engines still had a plug at the back like a dummy distributor to drive the oil pump. 

now as with anything produced that could possibly fail, of course my old man owned one of these engines also in an early 80’s station wagon. actually i had a few relatives that owned these as a kid. they indeed would get 30mpg in town, and were some noisy bastards that didn’t like cold weather. these things had weak blocks and were known for popping head bolts and cracking the block- after all it was a gas block not a diesel. by 1981 gm figured it out and re-cast the block heavier to solve the problem, but it was too late they had such a horseshit reputation that they were discontinued soon after.

 the later diesel blocks were given a “DX” designation. these blocks were beefy and could have the boss for the injection pump machined off, older heads and intake installed, and you could enjoy a 9:1 compression gas engine with beefy block and steel crank. some guys will overbore the hell out of these blocks and squeeze a 400 or 425 crankshaft into it for racing engines. not real cost effective though.

Olds Engine 64-76

 in the 60’s there were the 330- 400-and 425 early olds engines which had a different lifter bank angle at 45 degees than the later engines . All of them had steel crankshafts. the 400/425 block is basically the same engine block as any of the 455 blocks other than that for the most part. the 330 is a different bore than the later 350 olds engines, however the crankshaft is the same journal and stroke as the later 350 olds engines so you can use the crank out of an older 330 in a 350 for performance. the flywheel pattern is different though.

Although i have heard guys tell me of 455’s in 1968, i am going to say in 1969 for sure that olds shifted production to two v-8 engines. the 350 and the 455. these and all later engines used a  39 degree lifter bank angle- so you guessed it the camshafts will not interchange with the older engines. the cylinder heads will interchange however. similar to chevy some had more performance potential than others, but in this day and age it is kind of a mute point with aftermarket heads available.

obviously like with any auto maker at the time there were factory options with both of these engines. ROCKET350 or ROCKET455 was more of a label than a designation and doesn’t necessarily mean it had more performance than an olds engine without the label. i think it was more of a sales gimick. the 442,w-30, and toronado’s did mix it up a bit. i am not going to keep going into the specifics as it has been a real sore debate with some enthusiasts over what went with what originally.

for the most part, from 1970-76 was the bulk of the oldsmobile V-8 engines that people deal with. those being the 350 and the 455. they were essentially the same but the 455 had more deck height. most of the accesory’s, covers, ignition, and how they mount in the car will interchange. although the cylinder heads were different from small block to big block as far as valving and chamber size, they were identical and would interchange if you have enough patience. the thrust bearing sits at the middle of the block rather than the rear for the crankshaft. firing order is 1-8-4-3-6-5-7-2 just like a chevy, but the distributor rotates counter clockwise and uses a hex key to drive the oil pump. the intake can be removed without pulling the distributor, but it can be a pain in the ass with some intakes. there were also two different timing markers- one for small block and one for big block: even though you can use the same dampener. water pump snout lengths were different, as well as front accessory set ups. pulleys can be a real bitch to get right on just about every oldsmobile i have ever owned.  it seems like they changed the damn alternator and power steering set ups every year from 68 thru 73. they also had both right and left hand alternator positions for non-AC and AC equipped cars.

Now, early 455 blocks are a bit more sought after and are marked with a big old “F” on the block. most of these were from 68-72 although sometimes they appeared in toronado’s all the way up to 76. when i started out into the oldsmobile shit, these were the blocks to have for nickel content. from 72-76 the 455 block had an “Fa” designation and omitted the boss above the starter on the left side which was used for a manual clutch set up. i have been told that the F blocks had more material at the ends where the Fa had more material in the main webbing at the center. to be honest there is no real difference between the two other than the older F blocks are worth more for the clutch boss for 442 collectors. both the F and the Fa block are ultimately the weakest link in the engine when you build performance. there just isn’t a lot of material on the main webbing of the block to keep it from flexing when you start to make big power with performance parts. so pretty much if you have a hard on to build big horsepower and torque with a 455 you need to invest in some kind of a girdle to help support you main caps.

400-425-455 cranks were all big heavy bastards at around 80lbs. all the 400 and 425 crankshafts were steel. some rare few 455 cranks early on were steel cranks, and are worth good money if you get your hands on one. most were a cast iron or a nodular iron. the nodular iron basically is a different casting that allows the crank to flex and take more load. they were marked with an “N,NAK or CN” on the front counterweight of the crankshaft. the nodular crankshafts are preferred and were put in the cars with tow packages or performance oriented from the factory in like a 442. really though, none of these crankshafts will be better than the other as the block will let loose first.

when you start to beat on these big blocks, the first thing to go is the #4 main bearing, which sets off a chain reaction through the bottom end of the engine. since the bottom of the block doesn’t have much for support, that big crank will flex like a fishing rod and take out the #4 main. this is my theory on it anyways. there are many things to do to get around this. bigger aftermarket main caps, arp studs, halo girdles, and even a full girdle that in corporates the oil pan bolts to help hold the crank in are all options. some guys also rework the oil system restricting the oil to the camshaft and top of the engine so it will force more oil to the crank. to me that’s more like robbing peter to pay paul.

basically on the big engines, a safe rule of thumb is if you keep the lift of your cam less than .500″ at the camshaft and keep it under 4500 most of the time, you won’t have a problem. if you want to push it harder, you need to look hard into having everything rebalanced, oiling upgrades, and definitely pump some money into the bottom of the block to hold the crankshaft in.

As i said before, big block cylinder heads used letter designations. the better heads are cast with a “C,CA, or an E”. these supposedly have the best flow characteristics. however all of them were meant for leaded gas, and probably have small valves. which put you back in the same boat as before: go get aluminum heads. the only reason i can see to pump money into cast iron heads is if you want a stock appearance for restoration/collecting. 

the next common head were both the G casting and the Ga, which aren’t bad. the all too common head though on pretty much every 455 from 72-76 was the “J” head. most people call them smog heads. considered horseshit for performance a lot of people toss them out. what a lot of people don’t realize is they have more iron in em than most of the other big olds heads. so with some pocket porting  below 4500 the J head gets the job done nicely. if you want to goat an oldsmobile guy- grind the “J” off and say they are” I” heads!

as far as valvetrain- as you may have read previously in another blog, there were two different lifter bank angles. the 400/425 being 45deg and 455’s 39 degrees. olds engines to be honest have a non adjustable pedistal mount rocker arm set up. the geometry is pretty much horseshit so when you get into radical lift cams, you must switch over the entire valve train to adjustable rockers-cut heads for aftermarket springs and seals, custom length push rods, and then swear at it a lot. so hear again- hello aftermarket heads.

with the 350 engines, pretty much you are stuck with the same valvetrain issues. However the bottom end of the block was MUCH better with more material on the main webbing and a smaller crankshaft. also being a smaller engine you don’t need as much camshaft so the valvetrain nightmare may not be as bad.  the better heads for the 350 were the 5,6,and 7 designations. #8 heads being the most common and basically the small block equivalent of the J head. you’re still stuck with the same heavy block(as compared to a SBC) and oiling system though, so in that respect there are still some of the same issues as the 455. you just have less rotating weight and more block to work with.

well that’s all for today. thanx

Olds Engine Section

371187339

Back in high school, one of my friends bought a 1970 olds 98. it was a beautiful old man’s car. i loved it, but unfortunately my friend was a dumb ass and wrecked the bitch twice, pulled the engine w tranny and scrapped it. bot times he simply over powered the corner he was turning in and put it into both a guard rail and a brick wall of a building. i’ll never forget the excuse he had. “Someone killed themselves in the car and the damn thing must be haunted. it drove itself into the wall.”

Anyways, it sat on the lower half of a shopping cart for the rest of high school and i went away to trade school.While i was gone i offered to buy it off him when i got back from school. My friend offered me the engine as a gift when i came back from trade school, he and his brother had decided to stick it into his pickup truck. it completely pissed me off. he never could get it to run right. 2 or 3 years later i got a phone call from his brother asking me to buy the truck and 500$ later it was mine. unfortunately it had a dead #6 cylinder- which was diagnosed by his brother as a a carburetor problem. overall, it took me 6 years to finally get own that engine.

Well, since it took me 6 years to get my hands on it, i spent some time during those years doing some research and it is basically where i ended up becomming an oldsmobile engine nut, along with most big gm engines like cadillac, buick, pontiac, and the like. as with any passion, you get to know the history along with the engine. So here’s a brief and incomplete history.

From the mid 60’s and the days of the 371 olds up to 1970 the oldsmobile v-8 underwent an evolution and had many different variations of blocks, cranks, and cylinder heads. i believe in and around 1969 the castings on iron crankshafts advanced to where they no longer needed steel crankshafts and the 400/425 engines became 455 engines. in 1970, as it turns out, most of the gm v-8 engines were 10:1 compression advertised from the factory. it was actually closer to 9:1 if you ask me. there were some rare high compression 455’s for the w-30 and believe it or not gm had the 455 hemi engine in developement, 5 of which actually were built and are in a museum somewhere. oldsmobile also developed nascar blocks for racing around this time period, which was also short lived. some of the nascar blocks are still running today at drag strips in the midwest, and they are of freakish capability leaving the line at 7000rpm and shifting the car at 9000rpm.

in 1971, emissions hit and the compression and design direction of these big engines changed. Basically most of the big engines were deemed to pulling luxury cars down the road. by 1973 most all the big gm engines were smog tuned with retarded camshaft grinds, egr valves, hardened valve seats for unleaded gas, and depending on where you lived even smog pumps. from 73-76 pretty much the olds engines were about the same. Although it was never the most powerful engine in the muscle car era, it was not the weakest. Actually of all of the cars that came from the factory i believe Buick had the most power in 72-73 buick gs.

in 1977, the big blocks were finally scrapped all together and the small blocks were basically fucked over- giving us the 260, 307,403, and the oh so infamous 350 olds diesel abortions. all but the 307 were pretty much abandoned by 1982 and the 307 persevered until 1990 before all the V-8 oldsmobile engines were scrapped- and not too many years oldsmobile was scrapped entirely as a car division of general motors.

Anyways back to that original 455. i ended up spending about 6000 bucks on it and it led to my first race car that you see pictured on the main page of the website. After i bought my house, my obsession grew to a collection of over 20 oldsmobile, cadillac, and buick engines- most of which are no longer here cause i had to buy diapers for my son. in the many years though of the oldsmobile hobby, i learned a lot about the engines- both building and longevity, and i will be posting most everything i know here in comming weeks. it is just too much to cram into a couple of posts, so i will be writing a whole section and breaking it up for easy referrence. and yes if you think my info is wrong- please go pound sand. thanx

Olds Engine Identification

Olds v-8 blocks had their I.D markings on the top front of the block behind the timing cover and infront of the intake. it was a 6 digit number followed by either a letter or a number. the Julian date can be found on a small pad in the casting under the cylinder head at the left front of the block behind the power steering pump, usually caked in shit and so rotted you can only read part of it. this is only somewhat critical for guys doing accurate restorations. cylinder heads had a marking to the lower left of the cylinder head near the left spark plug as you face the head.

i consider there to be two generations of oldsmobile v-8 engines. Prior to 1977, Big Block olds engines used letters on both the block and heads, small blocks used numbers. these were the 330-350 small block engines, 400-425-455 big block engines. there were several variations in both heads and blocks from the mid 60’s through 1976. some are worth big money- some are scrap metal.
Starting in 1977 they abandoned the big blocks all together and redesigned the small block castings and heads. often referred to as smog motors, this generation of engine was the 260-403 engines, including the often seen 307 of the 1980’s. these engines were marked on the block and head with both a number and letter, like a 7a or 5a as an example. it happens frequently that you buy a 350 from a late 70’s car that looks identical to an early 70’s engine and it turns out to be a complete piece a shit for any kind of a serious build platform to start out with over an older engine.

i found a few old I.D charts in my library that should help you guys to reference where to look and what you have when you have an olds V-8 you want to identify. it is by no means completely accurate as over the years many parts were mixed and matched for auto repair and performance, and has been disputed by many olds websites and enthusiasts over the years. you may need to copy it to your computer and blow it up to read it.

olds crankshaftolds blocks
bbo heads
sbo heads

Engine Build #3: Top end

S3700155Now what in the hell is this? well, after i got the bottom end of the block assembled and went through my dial-in to set my camshaft and timing, it was time to start on the heads. on the oldsmobile v-8 cylinder heads, both the center exhaust posts of each head feed the exhaust crossover to the intake. good for cold weather/ not good for performance. Chevy cylinder heads would also use either one or both center exhaust ports for the same purpose, but it was not as severe as on the olds heads.  there are numerous ways to block these off using block-crete, epoxy, and there is also some kind of a goofy zinc alloy you can use(which can melt). the way i do it is melt down some scrap aluminum and pour it through the exhaust post openning until it fills just below the exhaust port on the back side. i melt the aluminum in a blacksmith’s ladle and use the rosebud on the acetylene torch for heat.  now it isn’t contoured at all for peak flow and there is a reason for this. if you contour it into a nice bowl shape, the edges of your plug will erode and flake causeing it to end up just like you see it anyways. the best i have found in doing this is to create a wall/plug of aluminum at the back of the exhaust port pocket and leave it. these are factory heads mind you.

 in this day and age if you want serious performance :buy aftermarket cylinder heads and say screw it. more often than not it is cheaper than jacking around fixing up factory heads. but here again, i am just seeking to improve a pair of factory heads a bit not re-invent the wheel.  on chevy heads for derby engines i have done this with good results, but just welding a plug into the intake seems to do about as much good on a chevy small block.

 Now the next step in fixin up my heads was to go throughS3700157 the valves.  Since i am on a budget i elected to do what i call a polish valve job, which is actually a service technique i learned in trade school from an old fart diesel mechanic i had as an instructor. basically you take lapping compound you can get at any parts store and spin it with a power drill instead of that ridiculous stick with a suction cup. i don’t have all day to mess with that shit. as you can see in the photo i have a quick-chuck style power drill. you put 3 or 4 dots of valve gringing compound on the face of the valve, stick it in as so and spin it with the drill at low speed; lifting and applying light pressure in 2 second intervals. you want to go low speed and yo don not want it to bark loudly or screech as it grinds. this causes vibration which will ruin the cut. after you grind, clean em off and check your valve action. your valves should pop closed and sit flush to the valve pocket. if it doesn’t that you may have bad valves or need to have everything sent to the machine shop. also while you’re at it, check your valve guides for excessive side play. if they are real sloppy your valves can stick open.

what you are doing by lapping the valves to the valve seats of the head is mating the two surfaces together to improve the seal of the valves. it also works to clean the carbon and other odd deposits off the seats. it is a cheap ass way of fixing up your cylinder heads rather than completely ignoring em after you go through the bottom of the block. this IS NOT an alternative to a valve job from the machine shop. regrinding the valve seats and valve faces completely is the right way to do this. a 3 angle valve job is also an excellent idea but i don’t really see the benefit of it unless you are going to be doing other port work on your heads and try to flow some serious cfm’s.

once you get your valves in order, it’s time for springs. although you can shim your springs according to wear, i always replace valve springs when i am replacing the camshaft. the valve spring tension must match the cam lift requirements otherwise you will have problems. i also replace my keepers every time. your retainer are a toss up. i elected to keep my rotators since they were factory. on chevy heads i usually omit the rotators in favor of solid retainers on both intake and exhaust. once you install your springs, take a rubber mallot and tap the springs to make sure the keepers seat fully into the retainers. you would rather have em shoot across the garage instead of comming apart and dropping a valve into your new engine!

it’s time to bolt on your heads. don’t get into a hurry here.  this is where the chevy and the olds engines really went two different directions. on your SBC’s, it can be as simple as bolting em on and setting your valve lash. on the oldsmobile: the rocker arms are not adjustable. actually they are a piece a shit. the aftermarket adjustable stuff isn’t much better it is usually re-fucked ford parts. so before you torque make sure your valvetrain will not bind- especially with an aftermarket camshaft.

for a non adjustable valve train: assemble your heads to your engine block with hand tightened head bolts. do not torque. put in a couple of push rods and a few rocker arms. check to make sure your valve lash is going to be spot on. you may need different pushrods or even convert to an adjustable valve train to make your camshaft work. you want a bit over zero lash for a hydraulic camshaft to preload the lifter(check your factory spec). converting to an adjustable rocker arm set up may or may not require some major machine work depending on what kind of heads you have to convert to an adjustable set up. this is why you don’t torque your heads until you know for sure.

if it looks good then roll it to maximum lift on both the intake and exhaust valve to check for valvetrain bind. now there are numerous ways to check for your valve clearance to the pistons and/or rocker arm bind.  the most unique way i have seen is using play-doh on the piston faces while swapping in solid lifters for checking. you then roll the engine over slowly and disassembe to check your pattern of valve to piston clearance in the play doh. .

 on a hydraulic lifter set up, an aggressive camshaft can be binding the valvetrainS3700161 during assemble and never know it as the lifters are collapsing as your spin the engine on the stand.  it will bind after start up and snap the front of the camshaft once you build enough oil pressure to pump the lifters fully. this can be due to either the valves hitting the pistons from incorrect piston: cam timing combination, valve spring coil bind, or the rocker arms are not slotted far enough and they bind on the pivots. a simple check is to stick a big pair of channel locks on the rocker arm at max lift of the valve and pull the rocker arm down until you have play on the push rods. this also checks for coil bind on the valve springs. i would not be doing the channel lock method on a race engine with aluminum rocker arms. this is a simple check that works well for a cheap build like this.

NOW, once you have ensured you valvetrain is going to be alright. torque your head to specification and assemble your valvetrain. start at the center of the head and work your way out. i torque the heads on in 3 stages: like 20-45-85 ft/lbs, have a sip of beer in between stages to give the head gasket time to crush.

i like to use the mr gasket head gaskets for oldsmobile they seem to hold up better over the fel pro. it’s also cheaper. for SBC, i tend to shy away from the metal head gaskets- especially on derby engines. even when using the ultra-copper i have had gasket sealing issues with stamp steel head gaskets. i had better results with the cheapo summit head gaskets for SBC over the stamp steel fel pro gaskets. it didn’t matter if it was a light or heavy casting heads either.

there ain’t much left to do on the olds at this point , but you chevy guys(and anyone else with an adjustable valvetrain) have to set valve lash. on these is do what is called the companion cylinder method. you basically take your firing order and chop it in half. so 1-8-4-3-6-5-7-2, 1 would be in the same position as 6, 8 the same as 5, and so on and so forth. this is how most engines for automotive work.

look at your rocker arms. you want to set your valve lash at or close to TDC compression of that cylinder that you are on to ensure you are not part way on a lobe. so to start, you bar the engine over looking at the rocker arms on #6. when the exhaust is just about finished and the intake rocker starts to move: you are at or near TDC of number 1 cylinder and can set your valve lash on both intake and exhaust of #1.

once set, you go about a 1/4 turn on the crank and watch the rockers on #5 to do the same thing as # 6  having both rocker arms in motion: this will center #8 at TDC compression and you can set both of those valves for lash. you just work your way down the line and should make 2 complete revolutions on the crankshaft ending up back at TDC#1 compression when finished.

the main reason i like doing it like this is because with aftermarket camshafts can be ground all over the place. so it may seem like you are on the bottom of the lobe and you really aren’t- causing lost performance from incorrect lifter preload.

Engine Build#2:Camshaft Dial-In

S3700153

if you have never done this, or never even heard of this, it’s called camshaft dial-in. although not as many people do it as should, it is something i had to learn to do by force cause of this damn oldsmobile habit i have. unlike the aftermarket for chevy, olds performance products ore usually not right. i have only had two timing sets ever be spot on to there advertised markings. believe it or not the most consistent timing chains i have bought in recent years are the summit racing brand timing chains!

in a nutshell, your engine is a rotating assembly. your camshaft is designed to orchestrate your valve motion in relation to the rotational position of the crankshaft. by dialing in your camshaft, you are verifying that your camshaft and timing chain are going to fire off your valves at the right time and the proper lift to what you want. like i mentioned, there are numerous timing chains and camshafts out there, and they may or may not be made correctly. hell even my edelbrock cam was a bit off on the exhaust valve duration. a lot of your factory cams and bad replacements are ground retarded from the get go- and some of these multi position timing sets that actually sit 4 deg retarded at the 4 degree advanced markings!

Now, i could sit here and write out exactly how to do a cam dial in, but a quick google search will reveal some spot on articles on how to do it, as well as video’s you can watch on the web. you can buy complete kits to do this as well through summit or jegs. what i will do is point out a few things that i do whi;le going through the procedure.

there are a few ways of doing dial in, i use the intake centerline method with a dial indicator at the lifter. this eliminates all loss of lift through the valvetrain. yes, you can lose quite a bit of advertised lift through a poor valvetrain(like the olds). i use the large moroso degree wheel, a home-made pointer i made out of a bolt, and a piston stop i made from a piece of angle iron and a few bolts. i have a hydraulic lifter that has been welded solid with a plug so it does not collapse and throw off the measure of the dial indicator.

once i center my degree wheel to TDC #1, i position my dialS3700154 indicator directly on the lifter of either intake or exhaust # 1. you then zero the indicator and crank the engine around to .050″ lift at the indicator. look at your wheel and see how it corresponds with your cam card specs. if it is not spot on, note the degree’s of difference. this is the first sign of your cam timing being way off. i go through the process for both intake and exhaust lift. if all readings are off by about the same # of degree’s, adjust your timing chain…or in some extreme cases if it is off by 8 degree’s or more from the card on both intake and exhaust, shit can your timing chain.

as a rule of thumb, advancing your timing chain will usually help your bottom end power-retarding it pushed the power band up the rpm scale. for the most part, you should achieve correct cam timing with the timing set installed in standard position. if the cam is way retarded or advanced from the cam card while the timing set is installed straight up- call the manufacturer cause there is probably a reason for it, like valve clearance to the pistons for radical lift . do not plan on buying a cam and changing it at the timing chain from the get go. although it can be a neat way to save money- just save yourself a headache and buy the camshaft you want. use the timing set adjustments for fine tuning not overhauling the cam timing.

i quit buying used camshafts or anything without a timing card simply because you really don’t know what the hell you have. you can use this process to read an unknown cam or a camshaft you have ran for a few years to check for wear.

once i have my cam timing set, i wheel the engine to TDC#1 and remove the wheel. slide your dampener on(sometimes part way) and see where your ignition timing mark is located in relation to the true TDC location between your indicator and the groove on the dampener. you’re checking to see if the outer weight outer weight of the dampener has spun on the rubber and moved the mark. if this has happened, then you need to shit can your dampener. on the SBC chevy’s there were a few different balancers and timing covers so you can really mess up where you set your timing.

Engine Build #1: Bottom End

S3700147

Well, i must be an idiot as i have decided to build myself yet another olds engine after i swore the damn things off.  I pretty much have given up on the 455 olds based engines as after about 10,000$ and 6 blocks. i have come to the conclusion the block itself has an achilles heal. the olds V-8 blocks like you see here have the thrust bearing at the center of the block. i theory is that on the 455’s, when that 80lb crankshaft is under major load like going down the track at the drag strip, the crank bends like a fishing rod flexing the block. the center thrust bearing aids in absorbing the thrust from the front 4 cylinders- but the back 4 cylinders have nothing to help it. basically the #4 main flex’s and shits out the main bearings. some engines do it- some don’t all i can say is balancing and camshaft selection are key with 455 longevity. also- buy a girdle for the bottom of the block. Better yet go buy a chevy based Merlin block and forget about it!!

Anyways, when i finally sold my 462 drag engine a few months back, i got this mid 70’s olds engine in on trade. last friday i tore it down and i have to tell ya, it is one of the cleanest Blocks i have ever seen.S3700146 it literally had a stock bore with no piston ring ridge on the cylinders. the Crankshaft was also spotless with normal wear on the all the bearings. so i elected to re-ring it for future use on a street car i have planned to putz around town in. i am using a mid 70’s 350 block, plain jane crankshaft and the original rods and pistons. the identifying mark on olds blocks sits right on the top of the block behind the timing cover. in the picture here to the right above is the serial number you would look for for the good olds 350 blocks. after 1976, the bottom of the block on most all but the diesel engines had large windows in the supporting cast iron of the block for the main journals making for a very weak block to begin with. in my opinion the only block stronger that these 350 olds blocks are the DX designation 350 olds diesel blocks of the early 80’s(which can be converted to gas).

Now to do up an engine right, your block, crank, heads, rods & pistons need to be checked for wear and damage.  things like journal diameter and cylinder bore wear and taper. if you do not have the machinist’s tooling to do it, find a GOOD machine shop(which can be hard to do) . if you are building a high dollar power plant, you should definitely have the block, crank, and heads magna-fluxed for cracks that cannot be seen by the naked eye. pretty much in my book any engine that will see over 350hp/ 5000rpm OR serious amounts of abuse should be checked. things like lifter valley crack can become major deals the more you push an engine to the limit.

 NOW, does this mean you cannot build an engine without a trip to the machine shop- of course not. in my case i started with a great core and have a 500$ budget to get the thing running, and it will not see serious abuse. if the machine shop is out of the question for whatever the reason….usually cost….here’s a list of things not to forget while tearing down, inspecting, and re-assembling you short block :

– i always check all 8 bores with a bore gauge for size and taper due to wear. visually check for pitting and wear to the top of the cylinder. slight ridge-ring is not a definite sign of needing machine work. a ridge reamer can take care of a lot of it. as a personal rule if it is over .010″ of wear you really ought to consider boring it out….however if you are building a loose derby motor, ring seal is not quite as critical so .010″-.015″ is not all bad. in that case the engine i built to run extremely hot and will actually run better as it runs hotter due to the tolerances tightening up. it’s a fine line- too much and you will have piston slap.

-always check the journals on the crankshaft with a micrometer and visibly look for hard wear and damage. you are checking for undersize and taper. if the bearings look bad- chances are the crank is screwed. even if it looks good, if your engine was making noise CHECK IT!  you never know when someone else has been into an engine haf-assed the assy with the wrong size bearings at some point in the past and it bites you in the ass(it happened to me years ago). if your sizes are not to factory spec, look over the crank for any markings on the ends. machine shops usually stamp an undersize on one end of the crank on the counterweight.

-check your pistons and the old rings. look for stuck rings. clean any and all carbon from the ring grooves with a piston ring groove cleaner so your new rings will not jam between the cylinder walls. make sure piston pins are free. check the rods for blue marks….some discoloration of the rods is fairly normal, blue indicates heat damage and it must be replaced.

-if you had spun main bearings or severe bearing damage, the alignment bore of the crankshaft in the block could be compromised and you will need to make a trip to the machine shop, or shit can the block if you have a pile of cores….LOL!

-if you are not replacing the camshaft take a pair of calipers and check EVERY lobe for wear. 90% of the time you will find one that is not up to snuff. always replace the timing chain. always dial in your camshaft. if you do not know how to do this- learn how to. over half of the timing chains on the market are not accurate, and camshafts may or may not be ground retarded in the timing from the get go. you can lose incredible amounts of performance because of this! on some applications it can cost you an engine at start up cause the valves hit the pistons!!

-stick your new piston rings into at least one of your cylinders with a piston to center them and check your piston ring end gap. excessive gap for a derby engine is not hyper critical. you just don’t want it to bind.

-if you are going to run it over 5000 rpm on a regular basis, having your rotating assy balanced is a good idea. if you are changing hard parts like rods & pistons and they are not factory replacement, you should definitely have everything re-balanced. new and oversize pistons are suppose to come from the manufacture already weighted to a factory piston weigh, but the quality control on some of these parts can be a little left to be desired.

-when you are installing engine bearings, do not touch the bearings with your fingers if you can help it. the acid from your fingers can put marks on the bearings. i put a glob of lubri-plate engine assy lube in the middle of the bearing and put it together. S3700149you don’t have to lick the bearings and fondle em like your having sex, you just need to throw some on there so it isn’t dry! i also use two pieces of 3/8″ fuel line with dowel rods stuck inside to not only guide the rod ends onto the crankshaft, but it also holds the bearings into the rod ends so they don’t fall out onto the floors while you are trying to install the pistons into the block leaving both hands free to run the piston ring compressor. always use red loctite on the connecting rod nuts.