Brian Wright

After my last thread I got a lot of good info and thoughts to research and read about so as the title says I'm going with a N/A e85 build. My goal is mid 400s at the crank, so here's what I have in mind. Ive got a stock bore low mileage 5.3 short block with new ring, I have a guy local selling a set of 862 heads with 2.02 intake valves for a really good price so I'm thinking of going with these due to budget, my first question is how much should I milk the heads and what head gasket should I use for optimal compression for e85? Secondly I need a cam and spring suggestion for this setup, I am partial to Comp and Tsp so a I would like to stick with them, what cam would be best for my setup?
Other info: I will be running a ls6 intake I already have and in thinking of running 42lbs ls3 injectors? Ive found a set for a good price so let me know if these will work.
The vehicle is 2000lbs and I'm running a 4l80e with 3.73 gears out back, the vehicle is solely my toy so idle quality is not important, it can be rough as a cob as long as it doesn't die at the light. It will be mostly street raced but will spend time at the strip too.
Id like max effort and power out of the cam as it's my toy, I also plan on a 125 shot.
let me know if you have any questions
thanks, Brian

omc8

iTrader: (7)

So you're going 5.3 e85 build . Is this going to be high compression 13:1 build? As for the heads , some may disagree but the 862 w/ 2.02 maybe a bit too big for the small bore.

Brian Wright

yes I'd like the best compression for e85, don't know what gasket and how much I should mill the heads to achieve this.
And I was reading where some people think that about the valve being too big but would it be worse then than a stock valves 862 head?

omc8

iTrader: (7)

What is your budget for this build ? And what car is this going in ? You do know street racing is against the law !

Brian Wright

Not a set budget but I will be sticking with a stock casting head and and rotating assembly. And its going in a 1946 ******. And yes Mom I'm fully aware street racing is illegal🙄

64post

iTrader: (5)

It would depend on the way it's tuned but I've heard of 14:1

Brian Wright

what is the max I could achieve with just head gaskets and milling? Would this even be feasible or should I look into 4.8 flat tops? Would the head gaskets and milling cause problems with a high lift cam?

64post

iTrader: (5)

No, you should look into pistons with high domes if you want high compression. The milling will help but with the small displacement engine your talking about you'll need a purpose built piston. The head gasket will used to get the quench you want and only help minimally with setting static compression. Just turn it into a 5.7 and compression come with that. Yes to good ported 862's
L

Brian Wright

Brand new pistons are out of the question, I can either run 4.8 flat tops or the 5.3 pistons and I'm gonna stick with a stock bore as it's low mileage and I've already hot it hot tanked and it's ready to go.

64post

iTrader: (5)

With that small displacement engine and stock style flat tops you'd be lucky to get close to 11:1, you won't need e85 for that.

Brian Wright

Correct me if I'm wrong but I'd still make more power at 11:1 if I use e85 over 91 though right?

G Atsma

E85 has less energy per pound than straight gasoline. The only way to take max advantage of E85 is with much higher compression.

Brian Wright

So you think I'd be better off to run 91 at a lower compression of 10.5:1, plus doesn't e85 help against detonation?

G Atsma

Hard to say on the lower compression. E85 DOES help against detonation due to its high octane from the alcohol content, but at a cost of lower efficiency and overall power. The only way E85 really pays off is with very high compression.

uraloser2me2

Without aftermarket pistons it will be hard to get the compression where you want it and not have piston to valve issues. My 706 heads are milled .044 and with 6cc domes it is only 12.2 to 1 compession.