bwarren337

iTrader: (1)

I was looking in to getting ls3 cnc machined heads for my 1999 Z28 and was wondering if they would work with a MS4 cam shaft..Any info would be greatly appreciated

Zbinkley

Different intake is also required.

Bowtiedford

iTrader: (9)

I thought they did not work due to the bore spacing is different on a LS1 motor.

mike c.

iTrader: (1)

Don't do it. They make great power numbers and people are blinded by the great flow numbers. When i removed my cnc ls3/l92 heads for trick flow heads i gained 20 hp under the curve and 15 lbs more tq over the ENTIRE rpm band. my car gained 3 tenths with a much worse 60 foot. Get good heads one time like trick flow or afr,you will gain more power go faster and you will not be sad you did my friend. try a 215 head from tfs or afr. Remember the big key''you do get what you pay for''.

Darkman

iTrader: (2)

Information on cam selection-

https://ls1tech.com/forums/generatio...47423-cam.html

JUICED1

iTrader: (3)

LS3 heads need a minimum of a 4" bore! So no they won't fit a stock LS1. We have some ported LS6 heads that flow as good or better then a LS3 head. Check out our site JuicedMotorsports.com for some more info on them.

mike c.

iTrader: (1)

Let me add one last thing. The ls3 head out flowed my trick flow heads and yet the tfs head made big gaines flowing less. There is more to a head then flow numbers. there is chamber design,valve job,valve guid honing,the quality of casting these are things that are over looked when buying budget heads. This is where i say you get what you pay for in quality and performance.

JUICED1-This was not saying anything against the heads your talking about. This is just me using two cnc heads in the past and running a AFR and a trick flow head on different motors and gaining big each time. due to that,i push the AFR and trickflow heads.

JUICED1

iTrader: (3)

AFR heads are legit! They make good power as well.

87silverbullet

iTrader: (11)

Its great that you made more power and went faster by going back to cathedrals but done right the LS3/L92 can make big power. It just takes the can do attitude and a little knowledge to get the power out of them. They need a different complement of parts to make power compared to cathedrals.

For example this thread with a motor done by TSP: https://ls1tech.com/forums/dynamomet...o-results.html

A.R. Shale Targa

iTrader: (2)

Ls1=3.898" bore
Ls2=4.000" bore
Ls3+4.065" bore...The General feels this is an adecuate size can to unshroud
a 2.165" diameter intake valve
I wouldn't use these heads on a 408 (4.03X4.00") unless it was a drag only
application...big split dur cam, high rpms, lotta gear
Street apps need torque, airspeed comes from an efficient port, ls3s are 265
cc volume

bwarren337

iTrader: (1)

I was thinking of going with ported AI ls2 heads. I was just wondering if i would have to do any cutting of any type...ex: flycutting... Any suggestions on heads with an ls1 with a ms4 cam, hooker headers 1 7/8, ls6 intake, ported polished ls6 oil pump, ls2 timing chain.

PREDATOR-Z

PTV clearance on a cam the size of an MS4 require checking/measuring clearance and maybe flycut if necessary.

Patrick G

iTrader: (14)

Please listen to the words spoken here. The L92 heads have great flow numbers, but do not perform well with a smaller 4.00" bore. Why? Because the intake valve is so big and it's crammed right next to the combustion chamber and cylinder bore. This really disrupts cylinder filling. You may not see this on the flow bench, but the dyno and 1/4 mile trap speeds don't lie.

And for what it's worth, the L92 heads won't fit on a bore smaller than the 4.00" anyway. And one final thing, you cannot run more than a 231 duration intake lobe on a 112 intake centerline before you are tighter than .080" piston to valve. Big cam guys will need to flycut or risk contact.

PREDATOR-Z

Patrick: Do you know of anyone trying a smaller intake valve like a 2.08 for instance, if so what were the results??
Valve seats probably need changing but can it be done?

Patrick G

iTrader: (14)

Yes, HK Racing Engines cut down the LS3 intake valves to something closer to 2.13". This still fit on the stock LS3 seats and flow numbers were around 400cfm. Sadly, the 6.2L 2010 Camaro they were installed on did not break 500rwhp. This is why I say you can't judge power potential only by flow numbers.

WheelsUp84z

iTrader: (14)

I have PRC 2.5 LS3/l92 heads with a ported LS3 intake and PTM 92mm TB. My cam was spec'd by the man above (Pat G) I have no complaints on RWHP number, or street/track performance. Its the total setup that makes or breaks a car IMO. Throwing together a lot of off the shelf parts wont always give you the best outcome. Nor will the biggest flow numbers and largest cam you can find.

11.7:1 402 (LS2 block) 244/256 on a 114 LSA cam. Put down 554rwhp, and has put my 37xx lb car 10.8x@132 with a M6, and thats with a very novice driver (i'm terrible). I drove the car on a 700 mile road trip and got 22ish MPG and you can usually find me cruising around on the streets with my AC blasting.

mike c.

iTrader: (1)

My car ran 10.63 130.8 on a 1.55 60 in a car that is 3480+my 230lbs(3,710). I got the intake ported and pat g did a cam spec for me. I hope to see 10.4 or 10.5 in a car i can daily and gets 20+mpg. I feel the trick flow and afr is a easier head to make more power and go faster.. BWARREN337-Good luck to you my friend.

bwarren337

iTrader: (1)

Thats all great info guys appreciate it...im going to keep doing some research and try and figure out a little bit more on what heads will go great for the setup i have...

MM98

iTrader: (13)

These use a smaller 2.04 intake valve. The flow#'s are insane but haven't had any luck finding anyone running them.

http://www.mastmotorsports.com/2010/...sembled&id=360