Hello, I am a newbie to the site and looking to take the plunge on a project that will most likely take several years and have plenty of learning along the way. I look forward to chatting with the folks here about their passion for Oldsmobiles.

I plan to take a not yet purchased 1970 Cutlass and swap out the rocket 350 and put in a built 455 coupled to a Tremec T-56 manual transmission.

As I " have to start somewhere", I am going to dive into the purchase of the 455 engine first as this will ultimately be the heart and soul of the build.

There is a local option for a good price that looks to be a '75 motor (seller determined this based off of the numbers on the transmission, I will look at the codes on the engine to verify), I have heard that the later motors were not as strong due to the fact that they did not need to handle as much power as the '68 - '70 units.

I suspect this is a Fa block with J heads (J heads for sure as I can see in the picture). My plan is to either buy C heads or Edelbrock performer RPMs so I am not concerned with the heads as much as the block itself.

My main question right now is weather or not the Fa block is going to be adequate enough for my build, I want to make some good power but plan to drive it a lot so I don't want to overbuild it to the point that it is cumbersome to drive.

The seller states these motors were taken from Toronados and kept them for replacement motor home engines.

Wondering if this would be a good starter for my project or if I should wait for an earlier engine to come available.

Any thoughts would be greatly appreciated!!!

 

The later blocks don’t have the clutch pivot hole, I’m guessing that won’t be a issue with the late model hydraulic clutch. Supposedly the earlier blocks have better metallurgy, but even if that’s true I doubt that will be a concern for your build.

Don’t skimp on the pistons and rods. Build the short block stout, you can always upgrade to top end. Olds pistons and rods are HEAVY! Put quality lightweight rotating assembly in it, it will stay together. Find a machine shop familiar with Olds. Oldsmobile engines have their own machining tolerance, build them like a Chevy and they don’t last.

 

I have a set of C heads that are mildly ported for sale. They made 400 HP on the dyno with my combo. I had a beaing clearance issue and decided to go with aluminum heads, so the C's are fresh.

 

X2 on the quality parts.
However its never been proven one way or another that there’s any difference in the metal of an Olds block.
When I can’t tell you is that the later blocks, 73 and up, seem to have at least as thick or even thicker walls than some of earlier ones I’ve checked. Go figure.

 

I seriously doubt there is a difference in metallurgy. I’m guessing Olds was more concerned with casting enough blocks to meet demand, as long as the casting was good enough for their needs performance wasn’t a concern.

I work in a factory that casts aluminum. I wouldn’t be surprised that the later years would be cast thicker. The diemakers who repair the molds sometimes have to grind the molds to repair them, that would make the casting a little thicker. I know very little about how parts are cast, just have seen the molds and talked with a few die repairmen.

 

Thanks for the responses, I will probably pick this one up then.

What is the general consensus about C cast iron heads vs the aluminum edelbrock heads? Are they worth the $?

The seller says that his dad picked them up (he has multiple olds engines, only 1 455 however) over 10 years ago and has kept them covered outdoors since. In the pictures there doesnt seem to be anything out of the ordinary in terms of oxidation, Do I need to worry about any internal damage? He stated the coolant was drained prior to storage.

 

Shouldn't worry to much about that. it would nice if it will turn over with with wrench .
You are going to change everything any way. you are probably going to bore the block and turn the crank.
Aluminum head will be a very good choice.
a performer intake and away you go.
Talk to Cutlass EFI he will set you up with your cam needs.

Gene

 

Depends on location if i store stuff covered outside at my house in newengland, its gonna be rusted stuck. In the southwest its probably gonna be nicer after 10 years than my stuff was to start with.

 

I am located in central Minnesota.

 

The nickel content story is a myth that won't die. Use a little common sense - why would that only apply to 455s and not every other block Olds made?

 

Minimum required for a solid rebuild, IMHO:

Magnaflux block and heads for cracks
Block cleaning
Line hone for mains
Decking
ARP bolts on mans/rods
Cut/polish crank
Resize rods
New pistons/rings
Balance job
3 angle valve job if using stock heads
New valves/guides/seals
New cam bearings
New main/rod bearings
New oil pump/pick up and drive shaft
New timing chain and gears
New can and lifters
New rockers and pushrods
New water pump
New gaskets

I may have forgot a few things, but plan on a minimum of $6,000 - 7,000 to do it right.

$10,000 or more if you go top shelf and use aluminum heads.

 

Are the solid main web 403 cast with the high nickel metallurgy? 😂 Might want to look for you me of those blocks, since EVERYONE knows 455 headers won’t fit on a Cutlass Supreme. 😂🙄

 

So I picked the engine up last weekend, everything seems in order with the crank turning with relative ease. The only issue was a hole in the oil pan that happened during transport. This is not a problem as the Toro oil pan was to be replaced anyways. The seller did not have time to remove the TH425 transmission form the engine so he threw it in with the deal. So now I have one of those i need to get rid of (If anyone is in need of one, I guess they are getting rarer) as I don't have any use for it nor the space to store it.

My question to the experts here is how long I can store an engine that is completed before putting it in a vehicle? Does the assembly lube eventually gum up and create issues if not run for a significant time before being put into operation? Does it make more sense to wait to break it down until I am close to using it? Can I disassemble and have the machining done but wait to do the assembly, collecting parts along the way? I don't want to spent the time and money on something only to have to redo it because it took longer than expected to put it to good use.

Also, thinking of the build itself, What is a good target to shoot for knowing it will be street driven? I am looking for good driveability( I'm not building a race car) but want plenty of power as well. 500hp build good? Too much? Any input is appreciated. Thanks

 

If it was me I would go with a factory W-30 engine as close as possible with the exception of adding long tube headers. OAI hood and it would be awesome.

 

What are your time constraints? And Budget? That will determine a lot.

 

I noticed the motor home guy stopped advertising a 455
Good luck with your project
C heads can be money pits if you are planning to do whole meal deal
seats guides etc etc

i have some big valve KA and GA heads that have hardened seats .. $200 to $650
And if you want cheap..... To buy that is $100 for 2 pairs of C heads parts / cores??
maple grove minnesota

Cheers
brian

 

My main concern is to do it right. My plan is to purchase a drivable car and run the 350 until I am ready to do a restoration.

as far as budget is concerned, I have not set one. Meaning if it takes longer to build to make sure I use the right parts to build to the best possible street drivability level, so be it.

Thinking of the build initially. I am planning on aluminum heads with a hydraulic roller cam, Line hone the main bore, bore the cylinders, turn the crank, head studs, cam, water pump, oil pump and pickup, etc...

One thing I am still considering is to increase the stroke. From what i've read, this will increase hp and torque at the lower RMP levels seen with street applications. With the added benefit of being able to use a wider variety of more readily available Chevy connecting rods.

 

In my limited experience....do the engine and transmission last as they take the least amount of time to complete. You'll see completed engines on stands on craigslist with "had to let the project go, my loss, your gain" and people might get back half of what they have in the engine. Get your budget, then your timeline and follow it as close as possible. Better to be waiting on an engine and transmission then it sitting in the corner of the garage possibly rusting away or rodents get in it.

Also....the trans. If you find a reasonably priced used T-56, sure, go for it, but I'm a huge fan of the TKO since you have to cut the floor either way.

 

As an FYI.... I am not sure of the type of assembly lube used on our Mondello-built engine from the late 80’s, but it was as hard as carbon and the engine was locked up because of it on the pistons/ring packs. This means it was also built and crated 30+ years ago.

You can see my thread about this if you search batten head Mondello, etc...

I do know that the white lithium assembly grease gets dried out and hard very quickly....

I would recommend assembling with a Gibbs racing break in oil and assembly lube or torco.

I would also tell you that the power for Oldsmobile’s is found like every other engine.... the heads/induction system and the cam (use a freakin’ roller cam, please!).

The stroker cranks make very little difference if you aren’t using very high flowing heads.

if you notice on our build, we had a first try on the poorly machined Batten heads with the mis-matched intake and a cam that was too aggressive to be controlled with normal valve springs that we were using...

this was a stock stroke 455 steel crank....

with all the problems, it made 474hp and wouldn’t rev out/fell on its face early on...


fixing the heads/intake, and keeping the same exact shortblock made a huge difference in horsepower and torque.


in all honesty, your engine will only be as good as your machinist and build quality allows...