ls4_newbie

Hi guys I was wondering if somebody could tell me which head stud I need to fit the ls4 block. I'm using the 317 heads if that makes a difference. The reason I ask is apparently there is a 11mm choice LQ9 and 12mm choice ls9.
Cheers

Dom87SS

iTrader: (3)

id guess they are 11mm since a LS9 was not even released for sale years after the LS4 was killed off. call a machine shop or someone like ARP and they will be able to look it for you.

91parkave

iTrader: (4)

why are you using 317 heads IMO it would be better to keep the 243's and thicker head gasket for boosting

ls4_newbie

I'm using the 317 heads and the thicker head gaskets to lower the cores soon to be able to run more boost safely as when I read into boosting these engines you had to use a 9:1 comp ratio to to be able run over 15psi

91parkave

iTrader: (4)

I would disagree and 15 psi on this car is some serious power I hope you got money for a transmission and a. 1" gmr chain otherwise the power will never get to the ground

ls4_newbie

Yes the transmission is not an issue I'm basically buying triple edges catalogue of parts then when I have something to work with I have a company in the UK willing to make a Borg Warner 1" wide chain, failing that ill get adaptor plates made to fit a different box

Brian396

iTrader: (3)

If you have E85 in your area, 10:1 and 15 psi would not be a problem.

91parkave

iTrader: (4)

Whoa dude if you have a line on those chains you're going to be rich look forward to the build man

ls4_newbie

Unfortunately mate in the uk E85 never took off and the only way to get it is from someone like vp fuels at about $120 a 4 gallon barrel

ls4_newbie

Thanks mate I'm gonna put these chains through some serious grief before we market them. But I'm wanting them to strong enough to take seriously high torque

itsslow98

iTrader: (18)

I agree, id rather have the 243s. You can make the same power on 10psi with 243s as you would with 317s and 15psi its all in the tune.

Also if meth is available over there id strongly consider it for IATs and octane.

91parkave

iTrader: (4)

^^^^^^^ this.

Also if not denatured alcohol and distilled water will work 50/50 mix I'm sure you guys in the UK have that at hardware stores

ls4_newbie

Yeah I was planning on running with meth injection anyway so hypothetical sakes if I was to keep the 243 heads and run 10psi what sort of power would you expect to see. Just to be aware I'm running on aftermarket management anyway.

itsslow98

iTrader: (18)

Hard to say without more details on the build. What size turbo, stock cam, stall etc.

Brian396

iTrader: (3)

GXPJAY was getting 505 hp at 12 psi with windshield washer fluid injection. https://ls1tech.com/forums/ls4-perfo...-kit-sale.html