I have a 88 camaro that I'm putting in a carbbed 350 but the 350 heads need to be rebuilt,if I put the set of good 305 heads on what will I lose or gain if anything?

 

305 heads are a great idea if you use the right ones. Try a set of '416 casting heads. They are 64cc's and will raise your 350 comp ratio to around 10.2:1 (assuming it is a normal 350)

Those heads certainly flow decent, and you will have to run 91+ octane.

A great cam to match up to stock 416 heads is a decent 93-94 LT1 cam with 1.6 rockers.

You can get the cam next to nothing, and 1.6 rockers are pretty cheap.

Good luck

 

the heads came from a stock 83 camaro 5.0 carbbed.the pistons I beleive are stock(they are 4 valve releifs on each??)and the cam I already got is a hyd. flat tappett and a 420-442 lift and 204-214 at .50 in timming

 

Chances are the heads are 416's which were dime a dozen on 305's from 82-84's since you are running a flat tappet cam.

The cam you have sounds like the "summitracing special" SUM-K1102
Which is actually a decent cam for those heads. If you use 1.6 rockers you will be just under the max lift for the heads and you will be well on your way.

Good luck.

 

can I use the stock rockers?are the 305 and 350 rockers the same?and yes it is the summit special,lol

 

You can.. but the stamped rockers get very brittle and have a tendancy to crack inside the bowls. It would be a smart move to get new ones. Summit sells "summit brand" ones really inexpensive. 1.6's is what I recommend for you.

And yes... the rockers are the same between all small block chevys

 

Thats not necessarily true... there are self-aligning rockers and non-self aligning rockers out there. Only the newer heads can use SA rockers if I remember right. The 416s use the 'narrow hole' method to keep the valvetrain in check, so you'll need non-self aligning rockers.

 

I could have sworn that the "narrow hole" was for center bolts.

Anyways, I made a mistake eariler. The 416 heads are 58cc

 

I was going to comment on that, I'm fairly sure all 305 heads are 58cc. Just picked up a pair of 416s myself.

 

081's are also a nice choice

 

As are 601s (better flowing, 492 chamber shaped, 53cc 305 heads w/ 1.84/1.50" valves) and 187s.

 

Just to bring this back up: Which "stock" rockers? The '83 rockers will work fine on '83 heads. The '88 rockers will not. The 350 rockers - depends upon what the 350 really is.
----------
Again, depends upon the 350. If they are truly flat tops with just 4 valve reliefs, your compression will probably be too high with 58cc (or certainly with 54cc) chamber heads. If in fact there is a slight dish along with the 4 valve reliefs, then you'll probably be fine.

 

Nope.. all SBC heads use that method, except for ones with a guideplate setup and the ones with self-aligning rockers.

 

305 heads work just fine on a 350, another happy camper here.
That's a weenie cam on a 350 though, like mucho smallo. Hope that's what you're going for.

 

Exactly the opposite. Slotted pushrod hole is the "old" way, through 1987. Starting in 1988, the pushrod hole is round, and the rocker is aligned on the valve stem itself (self-aligning rockers, they're called). Centerbolt covers started in 1987. So, no direct correlation between centerbolt covers and rocker (pushrod hole) type.

 

I always depend on you to bring up the old ways. I am just messing

 

1990 up is all "new-fangled" stuff to me. . .