pdasterly

iTrader: (4)

I have a forged ls2 403 and want to know which heads should i use for daily driver, street car. I have a set of ported 243's from corvette with sodium filled valves 64cc. Also have 317's ported by same machinist, guessing regualar valves 72cc.

car has max pullied d1sc, fmic

MUSTANGBRKR02

iTrader: (91)

You need to figure what compression ratio you would like and pick the head based off of that. So you need to know a few things about the shortblock to figure that out.

pdasterly

iTrader: (4)

9.1 compression ratio according to mahle, engine has factory crankshaft, forged rods and -20cc pistons. the pistons are oversized making the engine 403 cu in.

turbo iroc

iTrader: (1)

I'm running l92 heads, can't deny the 265 CC runners and 2.16 valves. L92 ls3 and lsa there, hands down the best factory heads out there.

killernoodle

He may not want to change his intake manifold, or switch away from a head he already has.

Cathedral ports only?

I say 243s, with the 317s I bet that brings your compression down quite a bit with -20cc pistons. The fact that you want daily driver tells me you probably would like more compression better.

You should be fine with stock heads and LS9 gaskets and good studs at 15lbs.

MUSTANGBRKR02

iTrader: (91)

Head CC will make that determination along with how far the piston sticks out of the head, head gasket thickness and bore etc. Mahle gives a generic rating based on a certain CC head.

L92 fox

iTrader: (2)

How is it a 403 with a stock crank?

westtexasbuff

iTrader: (40)

LSAs ftw, they are casted with a better material than the LS3/92s and are 68cc chambers. Here are mine ported.

pdasterly

iTrader: (4)

going to get some ls3 heads, I didnt want to change my intake, not to many aftermarket options. bbk should make a ls3 metal intake

westtexasbuff

iTrader: (40)

LSAs have the same rectangular port as LS3/92s, so you wouldn't have to change your intake. You can get them cheaper too brand new, I got mine $315 shipped bare for the pair.

LSevil1

Interested in this as well. 317's, in case you go to an F1, boost > compression on pump 91-93 oct.

pdasterly

iTrader: (4)

my bad, I have a unknown engine size, seems online calculator is wrong

killernoodle

If he currently has cathedral port heads/intake, he would have to change his intake for l92, lsa, etc.

bonestock_442

iTrader: (1)

Who ported those LSA's WestTex? They look awesome.

turbo iroc

iTrader: (1)

Don't forget you also need offset rockers on the intake side.

westtexasbuff

iTrader: (40)

My bad, I misread his post about going to LS3 heads, I thought he already had an rectangular port intake. But yepp, if he is switching then he will have to get an LS3 style intake. LS3 intakes are not that expensive, and work good.

Can't say on here, since he's not a sponsor, but it was a local shop here in town.

PRAY HRD

iTrader: (119)

in your other post you said the lsa's were 68cc chambers, and i could be wrong about this, but when i was looking at the lsa heads months back i couldve sworn they were 75cc as cast. please correct me if i'm wrong.

westtexasbuff

iTrader: (40)

They are 68cc as cast, but can be 75cc with some work to them.

http://paceperformance.com/i-6255521...te-engine.html

"Cylinder heads - 12604860 aluminum L92 style with 68cc chambers"

PRAY HRD

iTrader: (119)

thanks a lot man. i know i read it somewhere they were 75cc but that person was obviously incorrect.