dman0712

How strong are olds 455 rods? Will chevy pistons and rods work in the 455? i will be sing the c heads and i found these pistons
SPEED PRO 400 DOMED SBC CHEVY PISTONS TELFON 4.185 5.7.

jensenracing77

i am not the guy for this answer but i do know that people have had a 425 steel crank off set ground to the BBC rod big end but also to a 455 stroke. they had to use BBO pistons as far as i know. i don't think you can use those.

Run to Rund

You would have to bush the Olds rods for Chevy pins. The compression height is wrong on those pistons. You'd have about as much compression in the oil pan as in the chambers.

cutlassefi

Too much compression with C heads and those pistons (about 12.5:1). You really need the 12.5 cc dished ones. With 80cc C heads and a 4.150 stroke crank (which I happen to have a 425 forged one for sale in that stroke) will yield you a compression ratio of a little over 10:1 and 457 cubic inches. You'll need to use an aftermarket 7.1 BBC rod bushed to a small block pin size as mentioned. Eagle makes the bushings. I have the rods and crank for sale in that configuration if you're interested. It was the way I was going to go before I decided to stick with a small block.

Run to Rund

You will definitely need special rods and crank with a compression height of 1.425. Stock 455 height is 1.74" Even the 9.5 cc dome won't help enough to get any compression with stock rods and crank. If you spend all that money, you wouldn't want to rely on those little grenades (hypereutectic cast pistons).

You sure won't get any 12.5 compression with stock rods and crank using those pistons.

csouth

Why not just buy high compression BBO pistons and save yourself a lot of machine work? Unless you have the ability to do the work yourself, you are going to spend the money one way or the other....

dc2x4drvr

What Csouth said, stock Olds rods are good to 400-450 hp.
Take a look at TRW or Keith Black for pistons.

procharged70cutlass

im gonna say this from experience . leave well enough alone and build it the way it came. when you start trying to amateurly experiment its gonna back fire. that is why the factory spent millions of dollars in r&d for these motors. heed the warning

MI455

meh, That's what hot rodding is about right? Experimenting? Factory stuff was made with as little material and as cheaply as possible, lots of room to play around!

Run to Rund

Factory rods are good, a little better with ARP bolts. They act a little "soft" and the big end can deform a little under very high power. As it turns out today, rebuilding them, polishing the beams, and installing ARP bolts costs about as much as a set of new aftermarket SCAT etc. rods. . .hopefully the new rods are made correctly and won't need massaging. Olds pistons are good but heavy. So are the aftermarket Speed Pro factory replacements. They also have .060" pin offset and 5/64" wide rings which can "flutter" at high rpm. You can lessen the load on those rods with light pistons and pins, and get zero pin offset with 3/16" rings all at once. However, if you choose Chevy pistons you will have to deal with different compression height and bushing the rods for Chevy .927" pins (Olds are .9805"). Then you need pistons with pin retainers and use floating pins. Go ahead and hot rod, but use an excellent, knowledgeable machine shop and be prepared to learn a good bit about engine component design.

BIGJERR

If you have to ask a question like this PLEASE do not attempt to work on your own cars......This is for your own safety...............Jerr

MN71W30

My 455 has the same speed pro pistons. Mine have a slight dish that keeps the compression around the 10.0 range give or take a little. I still need premium gas, but my 455 runs very strong and I'm pretty sure it will see a 12.99 next summer with the factory manifolds, it went 13.1 already. I agree with procharged, Save your self some headaches and buy the right ones from Summit.

BIGJERR

Hotroding isnt about making a time bomb tho......Chevy parts can be used in a Olds motor but you better know what your doing.....

rtpassini

why use chevy parts? do they not make any parts in equal quality for an olds?

380 Racer

They are not actual Chevy parts. They may be Chevy style and a spin-off from a chevy. In my SB I have pistons that a SBC ever came with. Or the 6.200 length rods never came in a stock SBC.

OK the Chevy parts are cheaper because they are making them for 50 kazillion Chevies out there. Also the chevy parts are most usually much lighter. There's two of the benefits'

procharged70cutlass

please show me you experiments that have worked and i will retract my commet. other wise im pretty sure you dont really understand what we are saying.