bkeese

I have a Rallye 350 (yea, I know it was just an appearence package) and want to make it run the way the General should have constructed it with a W31 engine. It needs to appear stock, with the exception of a W31 intake. It has a TH350 and will be gone thru and a larger stall TC installed. I do have an OW TH400 that I could use if need be, but would prefer sticking with the 350 and selling the OW. It is a factory 3.91 posi, so those are the gears I'm sticking with right now, along with the 4 core radiator. I have done alot of research and completely understand it needs head work. Does any one know of a shop that does CNC porting on SBO, probably not?

My objective is to be in the low 12's and to scare the hell out of the 11's. So, it appears I need something near 400+ hp.

So, how much head work do I need and I perfer to do it, can I?
Do I need to grind the crank for sbc rods?
What type of cam? Do I need to go to a hydraulic roller?
What cam would you recommend? Rough idle is a must!

I'm looking for recommendations, lessons learned and build threads with similar desires. I'm not looking for a crate motor. I will be building my original block.

Please keep the 455 remarks to yourself. That would be too easy!

What do you think? Easy task? Must have aluminum heads?

455man

Check out the head porting thread. You'll probably need most of that work done. Roller cam would build more power. Aluminum heads would be a good idea also and would save you some time on head porting. I'm sure others will chime in with specific set ups. The rallye 350 is not just an appearance package. It was a healthy 350 in a 442.

pogo69

to answer your question properly.... how much cash do you want to spend?

oldzzy

I think it was on the old ROP site that Bill Trovato built a pretty stout "stock" appearing stroked 350. He might be the one to call.

tonycpe

i am running the BTR stroked 350 in my car . has over 500 hp call me if you want details , you have a pm.

bkeese

As little as I have too to achive my goals.

Fun71

Why the W-31 intake? Isn't it just an aluminum version of the factory iron intake? There are much better intakes for actually making power. Performer RPM or a single plane, depending upon what cam you end up with.

cutlassefi

I'd be interested in the specs, I'm sure others would be as well.

If you're ok with not using stock heads then I'd do the Procomps, otherwise just put a set of big block heads on it, cut enough to give you the compression you need with a set of flat top pistons.
Then stroke it to 380, a good hyd roller in the mid 230's@.050 and either an RPM or Street Dominator intake. Add to that a 750cfm carb and you should be able to reach your goals. The 3.91 gear helps, make sure you're still making power at the rpm that gear will require.

oldsmobiledave

Likely because they are lighter and still fit with OAI

Most Rallye 350 cars that I have seen came with 3.23 gears. Optimize your current engine by dyno tuning it then change to 3.91 gears. Enjoy the new found acceleration.


Oops...just read back & saw that you already have the 3.91s. Best way to go is to decide FIRST how much money you have to spend then decide what will give you the best results for the money you want to spend.

pogo69

that was a good answer an offy dual quad tunnel would be nice or a edel torquer maybe a 750 holley, elec fuel pump cam would be a tough choice an old jm 44 would rock the boat high stall converter head work and your good to go

those btr set ups sound interesting

HWYSTR455

My hand is raised, would like to know the specs. Shouldn't be a secret anyway. Certainly have to be aftermarket heads and run some lofty RPM I would think.

Pretty solid advice cutlassefi, could probably do it without stroking it, but if you're doing it, do it.(so to speak).

I'm almost ready to take my rebuild to the track, have my fingers crossed I will break into the 12s. My guess is it will be close if I don't, and that's with less gear, less cam, and iron heads. I could have gone bigger on the cam, know I would do it then, but this car has power brakes and AC, plus my daughter needs to be able to drive it.

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bccan

"C" heads made into "6" heads w/ a little weld or epoxy, wouldn't have to put a whole lot of money into them if your trying to keep it stock looking. Modified W31 intake would need some work but would also retain a stockish appearance, at a cost.

firefrost gold

Knolton thunder heads does a cmc iron head . BTR has done some surgical work on heads that can make your Big Block c head look like a 6 or other numbers in his book the D heads that are for a stock looking race car are not D's at all.

s i 442

Your already shooting yourself in the foot.
Low 12s with an olds 350 is going to be some thinking, mostly out of the billfold.