Wally

Here are some questions for the experts out there.
Is it possible to use the 371 Crankshaft in a 324 block?
If it is possible, what modifications have to be made to the block?
What is the required piston/rod combination required?

Wally

oldsmobum

The main bearing journals on the 371 are larger than the 324. I'm not sure that you can align bore those journals to the size. There are many tricks to help make these engines rip because they were very popular drag race motors in the 50's and 60's... Do some lurking on the H.A.M.B. there is a lot of good information over there on this topic.

Wally

Oldsmobum,
With a 371 crank and a 0.040" overbore in the 324 it becomes a 355. The right cam and carb combination and it would be pretty hot little engine.
I've started surfing the HAMB for more details on fitting the 371 crank into the 324 block.
It sounds like I need to start looking for a crankshaft.

Wally

59-59-59

Remember that not all 371 crankshafts are the same. 1957 and 1958 are the same while 1959 and 1960 are in a different class. Some differences are clearances and different main and rod bearings are used. Make sure you do your homework on this one

Wally

Thanks 59-59-59,

I'm guessing that the '57 & '58 371 crank is the closest to the 324 but I will be checking it out.
Any ideas where to find the details?

Wally

Tedd Thompson

Wally, why not just build yourself up a 371 from the get go.The 371 has better heads plus the cost of special machining and access to hard to find parts are going to add up fast. Just paint it green and no one but a true Olds nut will know....Tedd

oldsmobum

Tedd is on to something. The 371 has a 4" bore, which is much more conducive to building horsepower. This is because it unshrouds the valves in the heads. The 324 has a pretty small bore at only 3.875'

Wally

I understand that the "easy" way to do this is just build a 371, but I am known for not doing the things the easy way.
I just finished building a SBC 283. It is bored 0.040 over (so now it is a 289 but we don't talk about that). I had a set of Corvette 327 heads from another engine so those were ported and polished and used like they would have been "back in the day". There are several other internal mods to improve horsepower.
Before that I built a "stock" looking Ford Flathead with all kinds of tricks to improve it that only a true expert could find, most would take a tear down of the engine.
So now I'll looking at this '55 Olds 324 I picked up for $100. I have a set of '56 324 heads in my stock of misc parts but I might look for a set of '57 heads. If the 371 crank will fit, with a 0.030 to 0.040 overbore it becomes a 353 to 355. With the right cam and carb setup it should produce some pretty good horsepower.
When I investigated parts cost, it wasn't that different between the 324 and 371 but I'm still in the planning stage.

Thanks for all your thoughts,
Wally

Olds Dad

Wally - Keep us in the loop on this thread - I've got a '57 371 short block in a '55 mated to a syncromesh (heads are bare and off the car) and I'm contemplating putting a '55 324 back into the car (for correctness) but I don't have a standard shift flywheel for a 324 - maybe Tedd is onto something in making the 371 look like a 324 - anyone know if the intakes interchangeable?

oldsmobum

Well if you want to get close to 350 out of the 324, I would bore it, not stroke it. Word on the street is with a solid core it will bore out to 4", making it a 346 cid. The shorter 371 pistons are the appropriate ones to use in that application as I've been told. It is something I hope to accomplish some day

Tedd Thompson

Olds dad, I think the intakes will bolt up but not line up because of higher deck height,holes not align.I have heard of hot roders back in the day using a aluminum spacer then placing 324 gaskets on one side and 371 gaskets on the other and machining to mate up the holes.Seems like a lot of work and still have to put up with sucko heads mated to a good intake.

Olds Dad

Yeah - not sure which way to go - the engine in my post car is a 57 371 according to the numbers on the block - heads were bare and off it when I bought it - engine looks like it has aftermarket pistons and it looks like it's brand new - but it's never been run and been sitting for years - no rust on the bores and it moves - so I have a potentially "new" engine, with bare heads - potentially 'built' - bolted up to the syncromesh in the car - but I've got no valve train or intake - then on the other hand, I've got a beatiful '55 324 (automatic) running, but no flywheel for it.

Sorry to hijack this thread - it just got me thinking...

Wally

Olds Dad, I understand how those things go. It's interesting anyway. Which automatic do you have? Hydro or Jetaway?

Wally

Olds Dad

Hydra-matic...so the pilot bearing issue is on my side - I may keep the 371 for something else (have four '55s) or sell it. All my other cars are Hydra's so I'd have the reverse flywheel problem if I went the other way.

Wally

Olds Dad, too bad you're so far away, otherwise we probably could do some parts swapping. I have an extra 324 4-barrel stock intake.

Wally

64Rocket

In the early 70's, i took my 324 block and bored it and used 371 pistons, of which I thought it was a 345 cid but 346 cid is close. The thing ran strong. I had gotten a set of heads and the J2 intake and carbs. That I put on the 324. I was young and dumb and thought they were 371 heads. The intake fit perfect. Maybe I did not have 371 heads, for you say there is some problems with doing that.
Anyway what I had ran great in my '50 Olds coupe. I used a trans-dapt bell housing and a McCloud flywheel with a Muncie 4 speed. AH, the good ol days.
I still have the coupe but the engine long gone.
Gene

Wally

Gene,
A 324 bored to 4.000" is 345.58 cubic inch so some people would call it 345 and some would call it a 346.
As far as the intake fit, the issue is when you try to install a 324 intake on a 371 block. The 371 has a slightly higher deck height which then requires a slightly different intake, either shim out the 324 intake or use the 371 intake.
I've heard that the 324 block is a pretty hard casting. It takes a lot to machine it 0.125 over and it also ends up with pretty thin cylinder walls.
I'm thinking 0.030 to 0.040 over and possibly dropping the 371 crank in to give me some higher displacement.

Wally

Wally

Just to follow up on this thread. I ended up buying a '58 371 and now I'm in the process of building it to look like the 324 in my '56.

OLDSter Ralph

Walt, I think you might just "Git R Done". Welcome back.