I decided to put a cam and assembled aluminum heads on my Pontiac 350 and call that good for this year... no one seems to carry heads for a 350... summit has them for the 400... any suggestions for a cam and heads combo that will help speed the car up some? will 400 heads fit the 350?
72 CC Edelbrock heads will work on a 350. May want to try KRE Kauffman Racing in Glenmont Ohio for an additional bump to 65 CC Kauffman Tiger heads.
AFA a 350, I would get with Mark at KRE on what he would recommend as far as a cam.
In my opinion, aluminum heads on a 350 will not yield you much in performance. 72 cc heads will be 9.1 to 1 and 65 cc will bring you in at 9.8. For a $2600 investment, I do not think you will be happy.
Si Vis Pacem Parabellum
1967 Starlight black PMD Engineering 400 Auto 1968 Alpine Blue 400 4 speed 1968 Verdoro Green 400 HO 4 speed 2013 1LE 2SS/RS Inferno Orange Camaro.
You obviously know what the new parts will cost, and have that much to spend. So, talk to the guys at KRE. They can build you a set of their 65cc D-ports, with smaller intake valves. No need for the 2.11 valves. There is a road racer on the PY site who had a set built, with 2.08 valves, if I remember correctly.. Probably 2.02's would be big enuff. That's bigger than the stock 1.96 intakes. (I believe the '69 350HO, with #48 heads, was the only early 350 to use 2.11 valves.) As mentioned, the Kaufman's can fix you up with the heads you need.
Then, with having more compression, you won't need a Voodoo cam. You can go to something like a Summit 2801. This cam is basically a higher lift version of the Pontiac 068 cam.
Assuming your shortblock is in good enuff shape to survive with more compression, the combo of more compression and cam, should add quite a bit of spunk to your 350. The alum heads will also take some weight off your front end. Add a Performer intake and alum water pump, and you'll be even lighter. With a properly tuned Q-jet, you should have decent power and gas mileage--a nice little street package.
Using the old iron heads will require new stainless valves, a GOOD valve job, screw-in rocker arm studs and hardened valve seat inserts. Then, if you have any porting at all done, you'll have well over $1000 invested. And, you'll still have the heavy iron heads. If you run 'em at 72-75cc you'll still have fairly low compression, and will need a small Voodoo cam, like a 256, to increase cylinder pressure. Of course, as always, this is just one opinion--and opinions differ.
Example: 350 + .030 overbore, 75cc heads, 5cc valve reliefs, .027 x 3.95 Cometic head gaskets, .020 deck height ( a guess)
Put these numbers into the CR calculator and the static compression ratio is 9.24, which should be safe with pump gas, with a regular cam, like the Summit 2801.
BUT, if you still have a standard bore and run the cheap Fel-Pro head gaskets that most use, the CR is only 8.78. The Summit cam calls for at least 9:1 CR. So, the Voodoo might be good in this situation. Now, I've read of several guys who have actually measured those old 350 heads, like 17, 47, 11, and found that MOST of them have bigger than advertised chambers. Those advertised at 72-75cc measured closer to 80cc. That would reduce the CR to 8.38. So, if you use iron heads, you'll need to have 'em measured and cut down, IF you want more compression. At 80cc, you will definitely need the Voodoo cam. IMO
Note: All these CR numbers are aprox. I had to guess at some of the numbers, to plug into the calculator.
Just to add on the head comparison; depending on fuel octane and dynamic compression, the AL heads are less likely to experience detonation. I would much rather have heads that allow for more tuneability in both timing and cam selection.
@jman; are you running flat top pistons and has the block been decked? Also, is it auto or manual? If auto, what is the TC stall? What is the diff ratio? There are several factors to consider before selecting a cam..
In my case, I had to change out the original #62 heads for a set of 6X-4's because of the low octane fuel here in California. I was detonating all over the place. If I had the $ I would've gone with AL heads. BTW, It's no fun to R&R iron heads with the engine in the car.
I'm just curious. Since this is the 1st gen site, there should be lots of guys on this site who have had 350 2-barrel engines. So, have any of you guys ever measured a set of virgin #17, #47, or #11 2-barrel 350 heads ? If so, what size chambers did they have ?
I read where one guy said he's measured several sets and none were even close to the 72cc number that some sites list.
I don't know where all these head info sites get their info, but this site lists the #17 and #47 heads at 80cc, and the #11's at 85cc.
I measured plenty of various heads. My large valve #16 are actually 77cc not 72cc as they are thought to be. even the heads off 326 have larger than 72cc, not sure what the chambers are on the H.O. heads.
I measured #46 350 heads I have, the chambers are 74cc.
I assume you mean the '69 400/428 #46 heads. Several head ID sites list these at 68cc. From what I've read, most Pontiac heads actually measure more than the listed numbers.
The only #46 heads I can find, that came on 350's were in '73 & '74. Those are listed at 98 cc for most, and 89cc for the '74 GTO. Of course, I can't confirm any of these numbers. As we know, there is a LOT of incorrect info on most all Pontiac ID sites.
This is why most everything on the interwebs should be taken with a grain of salt.
I sold a friend of mine a set of 1970 RA3 that were milled down to 68cc. He has these on a +.030 350. His compression is in the range of 9:1- 9.2:1. Engine runs great.
From what I've read, most Pontiac heads actually measure more than the listed numbers.
^^^^^This. All those specs (compression ratio, cc's even cubic inches in some cases) are "advertised" numbers, rounded up or down for one reason or another. That 350 is really a 353.6
