I'm looking a tweaking my 72 350 engine. What heads should I put on it?

TIA for your help!

 

For factory heads 5 or 6 will be your best bets. Chamber size is still reasonably small, they flow well and it's easy to put in bigger valves. Next best would be 4 or 7 (which should already be on a 72 engine).

Put it this way- they got 315 horses out of a 330 using 3's and 4's, so they can't be but so bad.

 

Thanks for the quick response.

What heads were on the W31 350?

 

Keep in mind anything pre 1972 does not have the hardened valve seats.

5 is the best, followed by 6 and then 7.

I think the W31 had 7's but the valves are bigger

 

Number 7/7a heads were for use with unleaded fuel. Starting in 71 they had hardened valve seats. The best flowing heads seam to be at the height of the W-31 development, the 70 #6 heads. Here is some flow numbers. Look at the #7 heads at the .200" lift exhaust flow with the bigger 1.6" valve size. http://users.erols.com/srweiss/tablehdc.htm#Olds

 

I have a few sets of SBO heads that I got hot tanked and squirreled away 30 years ago. As noted above, for best flow, put in the standard 2"BBO intake valves with the 1.62" exhaust valves.

 

I have a 72'; on the 7A (A is subscripted) head Intake is 1.875 and exhaust is 1.622. The W31 head had 1.995 intake and 1.624 exhaust with the #5 heads, but they're pretty hard to find.

The 7A heads are actually pretty good and for the money to purchase #5s you could take your 7s down and have them ported. Then maybe think about throwing in a little bigger cam in like a Crane powermax. At that point you'd be pretty darn close to a W-31 top end.

 

would it be worth it to track down a W31 intake or is there an aftermarket intake that would do the same (or better) ?

I want to really wake this engine up while retaining a stock appearance. I will keep the Qjet and have it rejetted.

Anyone have a streetworthy 350 engine, running on pump gas that runs like a scalded cat and would care to share the specs? I'm kind of spoiled by my 72 Chevelle 454 with 462hp and 535tq.

I would say that my budget is around $3500 to $4000.

BTW, the engine was rebuilt stock (.30 over) by the prior owner less than 3500 miles ago.

Thanks guys, I'm new to Olds performance.

 

This one might work for you, but I doubt it could be done for only $4 grand.

edit: just noticed that it has Edelbrock heads too.

 

The W-31 used #6 heads. These are supposed to be 64 cc and 2.00 intake valves with 1.662 exhaust. I have a set of these heads and an Edelbrock RPM intake. I would suggest # 5,6,7 or 7a heads. Try not to go with more than 230 duration@.050 Isky makes some Really good Cams for Oldsmobile.
Hope this helps.

 

Closer to 70 CC. One of the Oldsfaq (442.com) uncorrected errors.

Yes they do, but they are "single pattern" grinds, and conventional Olds wisdom dictates "dual pattern" only.

Another of the many things I found out (via the Internet) that I've been doing wrong.

Norm

 

Me too Norm. The cam in my 461 from Bullet is an Ultradyne design that is single pattern. And I like it just fine.

 

Tim at Bullet still likes the single pattern cams, and they most certainly work. There are plenty of Olds powered cars running very well with them. But, many professional grinders and not "internet experts" like the split pattern to help out with the disadvantaged Olds exhaust ports. Harold knows a fair amount about cams in Oldsmobiles and his designs are split, as are Dave's at Engle and on and on. It would be ridiculous to say that an Olds can't run well with a non-split cam.

 

Yes it would.

That is why no one said it.

Norm

 

dick miller racing says #5's flow best..

i like 7A for the hardened valve seats.

 

If you have some port work done to the heads you have now will make all difference in the world. You can have bigger valves put in and you will be far ahead of any head you may think is out there. And you will still have everything all stock looking.

Gene