New pistons and 64cc heads.

after saying that rebuilding the engine will most likely cost more than buying a crate engine with more power a a good warranty.

look at Blueprint Engines.

 

Hey everybody, brand new to the forum.
I am looking for some wisdom and advice on an engine build I am just starting out.
Here’s my situation:

I just torn down the engine in my Camaro to the block, and I learned that the block is a late 70s, low compression block with dished pistons. The exact part number on the pistons is “H580P .040”.
Now, I am pretty new to the whole engine building process but from what I understand they’re low compression, bored .040 over pistons. The engine had 58CC “416” casting 305HO heads on it.

I have a comp 268H cam I got for a steal, and I wish to run it. I have the option to either Buy a set of 64CC aluminum heads, or I have a friend that has a set of 56CC aluminum heads I could buy.

My main question is, do I go with the 56CC heads to boost compression for the cam? Or stick with the 64CC heads? I can try to provide any more details possible if needed.

Thanks y’all!

I would get quotes from local machine shops to see if the block will be OK to use. If it needs more boring, it may not be usable. It then becomes a matter of money and also a 350 is always better than a 305.

 

Understood, if I REALLY didn’t want to pull the engine and go through all that, would the 56cc heads maximize what the block offers?
Totally agree on the engine pull/build vs crate. Unfortunately I’m just not in the position to be able to pull it. So, just trying to maximize what I’ve got until I can properly buy a better engine.
Also, just to clarify, it’s a 350 bores .040 over

 

I'm confused since you put this in your original post:
"I just torn down the engine in my Camaro to the block, and I learned that the block is a late 70s, low compression block with dished pistons".

 

What heads are the 56cc ones? If they're stock aluminum corvette heads, then your just bumping compression up, but not much flow gain. Again, if it's the stock aluminum vette heads thhn stock vortec heads from a truck flow better. 350 in my camaro is a crate 8.5:1 motor with 76cc heads. I replaced the heads with 64cc vortec heads and a comp xe262 cam, and for such a tame motor, it runs good.

 

They’re the Trick Flow Super 23 heads. 56cc chambers, 175cc intake runners.

 

@fairfax1000 I think the OP is saying somebody put 58cc 305 Heads in his 350. This was something people did back in the Smogs days to boost compression on the low compression engines. Downside is the flow terrible so most of the compression gain was lost due to flow.

 

Right on the money.
Previous owner had the engine put in. I’m leaning towards going with the 56cc heads, I figure the loss of a couple CCs of combustion chamber but increasing flow will net the best gains given what I’m working with.

 

Run the Trick Flow heads. Have them surfaced to decrees the chamber volume slightly more and use the thinnest head gasket you can find. You won’t have V/P clearance issue with thad cam & piston combo.

 

I haven’t done the full math and don’t have enough data to do so, but that piston has -20cc volume, which combined with a 56 - 58cc combustion chamber should result in a 9.2:1 - 9.5:1 CR depending on deck height. This is a perfect CR for the cam you’ve selected.
if this is a stick car I highly recommend running an L79 327 cam grid. It’s to this day a better hydraulic flat tappet profile than most offered by the aftermarket.

 

I haven’t done the full math and don’t have enough data to do so, but that piston has -20cc volume, which combined with a 56 - 58cc combustion chamber should result in a 9.2:1 - 9.5:1 CR depending on deck height. This is a perfect CR for the cam you’ve selected.
if this is a stick car I highly recommend running an L79 327 cam grid. It’s to this day a better hydraulic flat tappet profile than most offered by the aftermarket.

Exactly what I was hoping for. I will definitely be going with the Trick Flows. I’ll take a look at the springs to make sure they’ll work.

thanks y’all for the advice, just what I needed.

 

One final thought.. regardless of which head you choose, ensure the valve springs are correct for the cam. Heavy seat and open pressures will destroy any cast hydraulic cam you choose resulting in a much bigger job.