engine ?
Thread Starter
Heel & Toe
Joined: Mar 2010
Posts: 22
Likes: 0
engine ?
my bro and i are rebuilding a 350 for his 78 because the motor that came in it turned out to be a 305 out of a 1985 camaro. we found a 4 bolt block and steel crank for $90 also came with rods and dbl roller timing chain. my question is what heads do we look for ? can we use the 305 heads? we are trying for around 320 to 350 horses. we will be using a performer manifold, 600 holley or edelbrock carb, headers, and a small performance cam, hyperutectic pistons. what cam would you recommend? thanks jim
Burning Brakes
Joined: Mar 2005
Posts: 861
Likes: 0
From: WNY
The very first thing I would recommend is getting that block and crank tested to see if they are cracked at all - I tried going that same route for the motor I had built. I tore apart a ton of blocks (at least 5 complete motors) and each and every one turned out to either be cracked in the jackets, bored to hell and back, or in one case completely cracked out cyl wall. Same with some of the heads - I had three different sets of used heads pulled off old motors and every one of them had cracks in them.
Is the crank cast or forged?
If you are bound to use older style used heads, the 461/462's are both very common for circle track racers when they are limited to the gen1 sytle and can be had for cheap if you can find them. They are pretty decent. You could also upgrade to the newer style vortec heads pretty cheaply. After the experience I had trying to find a good set of used heads I finally just gave in and bought a new set - I figured at the rate I was going it was better to just spend more up front than have to worry about a crack showing up a month or two after I got it running.
Is the crank cast or forged?
If you are bound to use older style used heads, the 461/462's are both very common for circle track racers when they are limited to the gen1 sytle and can be had for cheap if you can find them. They are pretty decent. You could also upgrade to the newer style vortec heads pretty cheaply. After the experience I had trying to find a good set of used heads I finally just gave in and bought a new set - I figured at the rate I was going it was better to just spend more up front than have to worry about a crack showing up a month or two after I got it running.
Race Director
Joined: May 2003
Posts: 10,956
Likes: 409
From: California
my bro and i are rebuilding a 350 for his 78 because the motor that came in it turned out to be a 305 out of a 1985 camaro. we found a 4 bolt block and steel crank for $90 also came with rods and dbl roller timing chain. my question is what heads do we look for ? can we use the 305 heads? we are trying for around 320 to 350 horses. we will be using a performer manifold, 600 holley or edelbrock carb, headers, and a small performance cam, hyperutectic pistons. what cam would you recommend? thanks jim
World products Sprotsman II
I am running these, although I did have them ported, polished and port matched, ........they are a great deal.....
I am running a 383, which is basically a 350 with a 400 crank. and I can Dyno well over 400hp at the rear wheels and 436 tq.... with these heads...
just my 2 cents
Le Mans Master
Joined: Aug 2003
Posts: 7,720
Likes: 12
From: Chattanooga TN
No, you cannot run 305 heads on a 350. The combustion chambers are too small and you will have way too much compression. Don't know where you are located, but I think I have a set of 461 cores if interested.
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Le Mans Master
Joined: Feb 1999
Posts: 8,351
Likes: 75
From: Tampa Bay FL
Most discount auto parts stores offer rebuilt cylinder heads for the small block chevy. For $400-500, you can get a reconditioned set of 882 casting, smog heads that were common from 74-81. I bought a set back in 1999 and they had larger intake valves (new) @ 2.00 and 1.60 exhaust valves. All new moving parts and they were cleaned/resurfaced and guaranteed NOT cracked. I ran the 882's for about a year and then I bought a nice set of DART Iron Eagle heads. 180cc intake runner, 72cc combustion chambers, 2.02 intake/1.60 exhaust valves, screw in rocker studs, max lift of .525.
However, if you also have to buy an intake, you may consider the massaged Vortec heads that allow up to .485+ (see Scoggin-Dickey's, Jegs, Summit website or any GM Performance Parts website). They often offer the vortec heads/intake and hardware in a package for under $1,000.
Either the DART or Vortec heads are easily good for 320-350 hp at the crankshaft with accessories running.
However, if you also have to buy an intake, you may consider the massaged Vortec heads that allow up to .485+ (see Scoggin-Dickey's, Jegs, Summit website or any GM Performance Parts website). They often offer the vortec heads/intake and hardware in a package for under $1,000.
Either the DART or Vortec heads are easily good for 320-350 hp at the crankshaft with accessories running.
Thread Starter
Heel & Toe
Joined: Mar 2010
Posts: 22
Likes: 0
zz4 heads
we can get some zz4 alluminum heads for a good price. are these ok heads? will they have the holes for the accessories? do you need a special intake or does a regular intake bolt down allrite? thanks jim
Le Mans Master
Joined: Aug 2003
Posts: 7,720
Likes: 12
From: Chattanooga TN
ZZ4 alum heads are the same as L98 TPI heads. They have a regular chevy bolt pattern (like pre '86 with slanted middle bolts) so an "early" SB intake will bolt right up. They do have acessory holes. They have small chambers so it will bump up your compression. These are decent heads, not great, not horrible. If you can get them cheap, they are probably good for your application.