Another what cam thread. Lq4 and 243's
Another what cam thread. Lq4 and 243's I'm pretty new to this, never built and engine before.
I've got an lq4 with 104k and a set of 243's with ~50k miles off a member here. Otherwise it's stock.
Vehicle is a jeep tj at around or under 5k lbs. nv4500 manual transmission and a set of block hugger headers. Keeping it n/a also.
Going to be taken off road but I'm not sure I should put emphasis on low end torque, meaning not sure if it will make a difference, as I'm used to the factory 4 cylinder and a massive 120 lbs of torque.
Would like to be around 400 rwhp ( just cause no real reason for needing)
A few questions. Should I mill the heads? If so how much and should I use a stock head gasket? I need to use pump gas not sure if it matter but here I only have 91 and I'm 1000 ft altitude. And I need it drivable. I would like to take it to Colorado and be capable at 10k feet.
Anything else besides a tune I should get? Supporting accessories etc?
I've got an lq4 with 104k and a set of 243's with ~50k miles off a member here. Otherwise it's stock.
Vehicle is a jeep tj at around or under 5k lbs. nv4500 manual transmission and a set of block hugger headers. Keeping it n/a also.
Going to be taken off road but I'm not sure I should put emphasis on low end torque, meaning not sure if it will make a difference, as I'm used to the factory 4 cylinder and a massive 120 lbs of torque.
Would like to be around 400 rwhp ( just cause no real reason for needing)
A few questions. Should I mill the heads? If so how much and should I use a stock head gasket? I need to use pump gas not sure if it matter but here I only have 91 and I'm 1000 ft altitude. And I need it drivable. I would like to take it to Colorado and be capable at 10k feet.
Anything else besides a tune I should get? Supporting accessories etc?
Since you can only run 91 octane, I'd opt to not max the compression. Just mill the heads .010 for a flat clean up and call Texas Speed for some GM head gaskets and new TTY bolts. They can also sell you an LS2 timing chain and a new LS6 oil pump for added peice of mind. If you want a custom cam I'd call Geoff Skinner at EPS...very happy w/mine. If you don't have the time to wait and want to pull the trigger on a shelf grind.....I really like this one here for ya.....http://www.briantooleyracing.com/nat...-camshaft.html
Brian's also the go-to guy for quality valvesprings/push rods....
Brian's also the go-to guy for quality valvesprings/push rods....
Im close to 400rwhp on my lq4/243 combo with stock exhaust.And on that dyno day I had a muliple issues..slipping clutch,failed alternator and very restrictive air intake.I run 91 oct on mine and my 243 heads are milled.030 with stock gasket.I think the comp ratio was around 10.5:1..maybe a lil more.
Havent been to the dyno since things have been fixed but its night and day since then.
Havent been to the dyno since things have been fixed but its night and day since then.
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Joined: Feb 2009
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figure out what compression you have after you mill the heads and buy the heads gaskets .then buy the cam to get a pump friendly dynamic compression ratio .with too much torque you mite be breaking drive train parts .what size tires ,and what gears do you have ?check out a Texas Speed cam kit ,or go to Tick Performance .are you using a ecm or a stand alone system ?do a valve job on the heads .
IMO the piston is too far out of the hole on an iron block motor usually to run a .040" or even a .045" aftermarket gasket. I'd run a stock thickness gasket.
I'd personally leave the heads alone as you can't gain much without losing a lot of P to V and you have 91 octane. You could mill up to .020 with the cam I'd recommend and possibly gain 10-12rwhp, maybe 15rwhp when the cam is added.
Jeeps being pretty light weight vehicles, I'd recommend this camshaft:
229/232 .615/.575 112lsa
I'd personally leave the heads alone as you can't gain much without losing a lot of P to V and you have 91 octane. You could mill up to .020 with the cam I'd recommend and possibly gain 10-12rwhp, maybe 15rwhp when the cam is added.
Jeeps being pretty light weight vehicles, I'd recommend this camshaft:
229/232 .615/.575 112lsa
Thanks for the help guys.
Went ahead and milled the head .01" just to make them flat. And I'll be going stock head gaskets.
I'll be running either 37's or 40's. And probably 4.88 gears.
I'll be using an ecm.
figure out what compression you have after you mill the heads and buy the heads gaskets .then buy the cam to get a pump friendly dynamic compression ratio .with too much torque you mite be breaking drive train parts .what size tires ,and what gears do you have ?check out a Texas Speed cam kit ,or go to Tick Performance .are you using a ecm or a stand alone system ?do a valve job on the heads .
I'll be running either 37's or 40's. And probably 4.88 gears.
I'll be using an ecm.
