olds 350 heads question

hey i need to know if its possible to put chevy 350 heads on a 72 olds 350 rocket? if not where would be a good place to find some decent olds heads

 

Chevy heads won't fit. A set of w-30 heads off a 455 are really good. A lot of performance can be gain by converting the heads to screw in studs and using adjustable full roller rockers. Good aftermarket performance cams really bring Olds motors to life. Even though the W-30 heads are Iron, they flow real good. Hope that helps

 

thanks also would any 455 heads work? if so which ones would flow the best other than the w-30s?

 

So what's wrong with the '72 heads? That was the last year they had decent heads before the smog heads starting in '73. You should have the 7A heads on the '72 350.

The best flowing heads are the 5's from the '68-'69. But, everyone that has a 350 Olds knows that, so they get pretty pricey on eBay or any other source.

I have a '70 Olds 350 that I'm dropping into my 37. I used this site for my research, it will have everything that you need.

http://www.442.com/oldsfaq/ofhed.htm#Heads

 

Man, I cant think of any reason to put a chevy head on an Olds 350.
The 455 looks good on paper but unless you are gonna rev it past 6000 rpm, there is no need.
Small block heads flow great in the intake side, the Exhaust side is OK.
Run a cam that accents the exhaust side and you will be golden.
lunati makes cams that really are for oldsmobiles( others often use chevy specs )
Edelbrock made 397 hp from a 350 olds with 7a(smog) heads, I would assume that would be enough ? (performer RPM package)
Chevys are like Big Macs, they are cheap, plentiful, and no matter where you go they are all the same.
But if you drive across town you just might find the best burger you've ever tasted, didn't come it a card board box.
Honestly, the 350 Olds is a Damn good engine, and should be capable of being scary fast without much trouble.
Check out the RPM package, or mondello performance, just because summits not full of parts doesnt mean the engine is no good.
BUT, if Revvin is your game those 455 heads will flow well past 6500 rpm.

 

All Olds heads will interchange. To put big block (400, 425, 455) heads on a small block (260, 307, 330, 350, 403, 350 diesel) you'll first have to drill out the dowel holes in the heads. All small block heads have a 3/4" number cast into the outside surface near the left end below the end headbolt and will be either #1,2,3,4,5,6,7,8,10, or 2A,3A,4A,5A,6A,7A. Most of the small block heads have 1 7/8" int. and either 1 5/8 or 1 9/16 ex valves. The #10 heads have 1 1/2 int. and 1 5/16 ex. There were three types that had 2" int. valves and were used mostly on the W 31 small blocks. These were some 5s and 6s and some 4As but you'd have to check the valve sizes to be sure. These heads all had 70cc chambers but the 4As were 83cc(77-80 403cid).
Big block heads had a letter cast on the outside of the heads in the same place and were:A,B,C,CA,D,DA,E,F,G,GA,H,J,K,KA. All the big block heads came with either 2" or 2.070" int. and all had 1 5/8" ex. All the big block heads had either 79cc or 80cc chambers with the exception of the '68 and '69 W-30 455 D and DA heads which had 72cc. These are as you might imagine, very rare. All the later W-30 heads had 79cc chambers.
Olds engineers adjusted compression ratios using different dish designs in the tops of the pistons. The main difference in performance figures they got was by using different camshafts and any olds cam will fit any olds engine, big block or small.
These number and letter designations were used from the begining of this series of engines starting in '65. The lower numbers eg. !,2,3, and letters eg. A, B, C etc. were used first and on up from there. When looking, you'll want to find a set of 7s and later or a set of Gs and later to get the hardened valve seats. On earlier heads you'll need to have them installed.
I'd recommend that if you can get a set of big block heads, try and get the cam from the same engine and swap it in also (be sure and use a degree wheel for accuracy). When you have located that set of heads, make damn sure that the tech who does the valve work knows the ins and outs of olds engines as the valvework has fooled more than one mechanic over the years.Yes you could swap in the expensive aftermarket valvetrain stuff, but remember, these engines have plenty of grunt with the factory stuff cause contrary to popular belief, even back in those days the engineers at the factory knew what the plan was.


Youth and enthusiasm is no match for old age and treachery

 

I´ve would not recommend a big block head on a small block engine for street use. I had the same plans many years ago but all Olds builders told me to use the small block heads. Big block heads will be a lot of work to no gain at all. Also, stay away from Mondello. Joe Mondello has nothing to do with them any more and it´s run by a guy that doesn´t do very good work and mark up the prices on stuff you can buy elsewhere.
For great service and knowledge try Smitty at http://www.mjproformance.com

Found this explanation on 442.com which are exactly what i´ve been told.

Yeah, you could bolt them on, but what do you hope to gain by putting a head with an 80cc combustion chamber (BB) onto and engine that thrives on heads with 65cc chambers (SB)? What would that do to your compression? Not to mention the larger ports and valves would enhance WOT performance at the expense of low-rpm response. I.e., if you wanted an all-out, race, on-or-off type engine, that MIGHT work. Otherwise, keep your SB parts on a SB and BB parts on a BB. There's also the intake port size at the head/intake interface discrepancy.


Jan

 

all i no is olds engines, rv cam, high volume oil pump, better intake 'anything but stock', carter type carb, if you have duels a cross over pipe is best for power and sound, no smittys or cherry bombs you will hate the sound. this will work om small and bigblocks and make sure the cam is dialed in for sure, and beleave it or not, your mpg will improve 3 to 4 per gal.

 

Olds 350's are nice. I've always had 455's, but I wouldn't mind a '68 "Ram-Rod" engine with a Muncie behind it. That W-31 cam had a pretty lumpy cam. I think the duration was 308 deg. Supercars Unlimited supplies factory spec cams made in the USA. I just received my '70 442 "manual trans" cam.
A bullet-proof 350 can be made from 330 steel internals. Real Olds Power.com is a good source of info.

 

another , i would not put bbo heads on a sbo.....do the math, its not a winner......sbo heads just arent that hrd to find.... FORGET THE CHEVY HEADS

is there more to the story (specs) about your small olds?

ther are better cam choices too!

 

There are always some nay-sayers in the crowd....ya I know,I know... a ford only in a ford; a mopar only in a mopar and on and on and yadda yadda yadda!
Just wanted to mention Mike that if you decide to use the bb heads and cam, you won't be able to use the stock intake. Actually, you won't even be able to use the standard edelbrock performer which is #3711 I think. No you'll need an edelbrock #7111 which was developed by a certain Joe Mondello for edelbrock. You may or may not have heard of him but he's a 75 year old man who's forgotten more about these olds motors than most guys will ever know. Throughout the early days of drag racing, Mondello-ported heads were constant winners, used by all the major names in the sport. He worked in R&D for GM for years and designed the small block chev combustion chamber which is also used by Dart and he created GMs big block open chamber design. His talents in R&D were also used by olds and the edelbrock #7111 that he designed was designed to allow using bb olds heads on a smb olds. It is designed with extra material above each runner to allow port-matching to the bb heads. You'll lose about half a point of compression which is really not that significant these days considering the quality of pump gas, but you'll gain breathing efficiency as long as you don't get tempted to over-cam. That's why I said to try and get the cam with the heads. You'll want a 750 cfm carb and tube headers. The center two ex ports are siamezed so what I did is cut a small tab of 3/16" plate roughly to size, and file-fit it into the center of the siamezed exhaust port, then mark it CAREFULLY and weld it to the back of the header flange. Then when you bolt the headers on, the tab goes into the head and butts up against the port divider. Don't forget to allow for the thickness of the gasket.
I have an olds small block in my '69 firebird cause I like to go real fast.(sorry poncho boys). I'm using a diesel block because it has the three inch mains. I took the crank from a '68 400 bb out of a 442, with a 4 1/4" stroke, had it de-stroked to 3 7/8" by offset-grinding and widened the rod journals .022" and to fit sbc rods. I used 6" sbc rods and adjusted comp. height pistons from Childs& Albert and turned the crank down 3/8" to shoehorn it all into the block. Had the assy balanced and put it all together using the cam from the 442. Put on the heads from the 442, they were C s, with just a good valve job and exh seats. I'm using the stock valve-train with the exception of the steel rocker bridges instead of the die-cast ones. Its a real strong setup as the crank-overlap is approx. 5/8' which is almost the same as the imortal chev 302. Runs pretty impressive. Its 414 cu in. and it has a ton of torq. I should put it on a dyno sometime just out of curiosity.

Youth and enthusiasm are no match for old age and treachery

 

a high volume oil pump will just make prolonged high rpm use kill your motor. Mondello and my machinist agree.
olds heads flow best when made by edelbrock. the improved heads are just so damn good.

 

olds and high rpm's don't go together, and yes mondello and kenny bell have alot of my money, and i have alot of there stuff for sure.

 

yeah im restorin a 72 cutlass supreme doin it resto mod so im just aimin for around 350-370hp right now with the rpm intake and edelbrock 1406 600cfm carb and stock 7a heads im around 260 and 4mpgs so in summary i would love more power for the pavement with sacrificing any more mpgs lol

 

See. Now you screwed up. You shouldnt of mentioned it was a 72 cutlas. The traditional guys are going to be chiming in and bashing you about being on the wrong site now. To answer your question: chevy heads dont fit on olds. Olds engines are wider than chevy.

 

If you can find them, #5's are very good for 350's. My next choice is to find #4's off a 67 330. The combustion chamber is the best of all small blocks and after having 2" intakes put in them (#4's), they wil boost 350 performance very much. Don't believe everything on the 442 FAQ. There are some mistakes that should be taken with a grain of salt. I have been building Olds motors for thirty years, both big and small blocks, and have learned some do's and dont's.

 

Drag car or street car ,I had a 69 rocket motor with a cam RV towing cam ,Had it up to 130 mph .It was fast even with the puny 2,56 gear ratio .And had a 600 holley . Had a 69 olds 4 door sports coupe .No post
If your motor has heads run them .If not post in the wanted section and someone here will contact you ,I don't know if their are any aftermarket companies that make heads ,Like World products .

 

I've been on this site a lot since I got my 55 Olds post project. I don't normally post here, but I'm an Olds guy and I think you need a hand.

No chevy heads do not fit, for one- Olds are 4 bolts per cylinder, chevy are 5.
That's like asking if mopar heads fit on a ford. (I really hate sbc)
Edelbrock and Rocket Racing both make heads. The Rockets are nice.
I do not use mondello, ever. I have found the truly fast guys DONT. Try Dave Smith Engineering, BTR, M and J Proformance, OPP, Rocket Racing.
The RPM intake is a good choice. The 600 Edel is not the best. The stock Quadrajet is a 750 and a better choice.(why would you go smaller??)
The stock cam w/ the heads?? I'll say this, down-rite will NEVER break that diesel block bottom end with that top end.

Check out real olds power .com if you are serious.

 

Natedrag makes a good point. I probably did overbuild when it comes to the bottom end. I think its because I have this phobia now as a result of an engine I was running a few years ago that went away when everything south of the cam all went further south...ouch! It was costly to say the least. I've been considering a hotter cam and valve train mods, but I haven't decided just what as yet. The bottom end setup that I'm using took a lot of planning and I'll probably spend an equal time planning the top. I'm guessing that a roller cam might be the way to go although a full roller setup is questionable to me as I've never been fully comfortable with the idea of aluminum rockers. I've also been wondering if there is the possibility of swapping in a rocker system out of a ford 460 as a low cost alternative way to raise the rocker ratio from 1:6- 1:73. These are just ramblings at this point as the engine is still in the firebird and I'm fairly busy with other stuff

 

That stock 350 OLDS will make more power than a stock 350 chevy.

the heads flow better and it has a big bore short stroke long rods, rhe 1970-72 heads are fine, small chamber and flow well, the bigger 455 olds valves fit right in.

4.057 bore, 3.385 str4oke 6 inch rods.

the rods and crank are tuff.

also a 455 olds will bolt right into a 72 cutlass, the dist, water pump, PS pump and all the brackets are the same.

for a street curiser a 455 cutlass is hard to beat.

the 35o olds runs hard too.

here is an olds forum

http://www.realoldspower.com/phpBB2/index.php

 

Okay, so this is some major thread necromancy, but i have been offered a pair of G 455 heads, and i have the 79cc 8 heads on my 350, the asking price is a couple hundred bucks, and Edelbrocks are expensive, considering i already have low-comp heads, should i go for it? Got an Edelbrock Performer intake manifold, and the engine's had flat-top pistons and a mild cam installed