I'm going to put in a used motor while I start putting the parts together for my 385 build. I want to do a cam only E85 motor, using a custom LE cam, and mill the stock heads as far as possible and use a .026 head gasket, so I was wondering how far can stock LT1 heads can be milled and how small the combustion chambers (in cc's) they can get. I want to make the most of the E85.

Also, would angle milling them say 1* give ANY gain, even if small; or would it cause too much of issue with the headers?

 

Subsribing. Don't know if it helps, but I know that LE said we could shave another .020 of my heads and they have already been cut .010.

 

I was thinking about .030 was what I had heard before, I just want to make sure, and also approx what the chamber size would be after that?

 

If you mill the heads you will, sooner or later, have to mill the intake as well. A firend of mine did that with his '93 and had fitment problems afterward...

If you're after higher compression to maximize the use of ethanol, why not use domed pistons?

 

Domed pistons require a full engine breakdown to replace the pistons, heads are easy to get off

I have been there, done that. I haven't had said fitment issues yet, but I only milled .010".

 

so ur going to put in a used motor in and want to run a higher comp ratio but dont want to pull the pan to check rod and main bearings to be on the safe side and replace them while the engine is out? if its already out u should tear it down and have the deck milled to 0 and then shave the heads .010 and use the impala lt1 head gasket that is .021 thick and use flat top or mild dome pistons to get close to a 12.5-13.0 comp ratio

u can mill .030 on your heads with a stock deck hight

 

I guess I misunderstood..I thought the engine would be out and built into a 383.....

 

Impy gaskets are .029, the OP has already mentioned the others that are .026. I was also recently told that chevy makes a .015 head gasket that when modified for an LT1 can be used.
I might look into that option when my heads come back off in the spring.

 

well autozone does have some .021 i think gaskets for the f-bod IIRC from last week

 

Well I'm not going to get new pistons for it, I already have pistons for my 385 build, will be shooting for about 14:1 CR on that build. My car has been down for over 1.5 years and want to get it back on the road and enjoying it again while taking my time building my 385 right. I have a Canton RR pan that will probably be going on along with a new oil pump with high pressure spring for a little added insurance on the used motor. I don't plan on changing out the bearings, except maybe just the cam bearings, thus the reason I want to find a lower mileage motor. This block is NOT going to the machine shop.

I just want to get my car back on the road and enjoy it while taking my time building my 'real' motor.

So if I mill the heads say .030-.035, approximately what will the chamber size be?