rennat_2006

iTrader: (10)

I recently picked up a 2004 lq4 truck engine that im going to be installing in my 71 nova with a t56 behind it.

Plans were to throw a decent sized cam in it, Switch to a ls6 intake manifold, and to ls6 heads. I have done some more reading and i may be wrong but i think that the ls6 and 317 lq4 heads flow the same but of course the chamber size is different. So i was wondering for a cost standpoint wouldnt it be cheaper for me to have my lq4 heads milled down instead of buying a set of ls6 heads or am i missing something?
Any other benefits to running the ls6 heads over the 317's?
I want to stay on pump gas but still have good power out of it.

I have heard some horror stories about ptv clearance on the lq4's because of the dished pistons, Is there a accepted cam number like how big of lift etc that you can go with before you need to get them flycutted? I would really rather stay away from going that far into the engine right now.

Thanks alot

A.R. Shale Targa

iTrader: (2)

Yes the 317 and 243 ports are similar but the chambers are different by
7 cc of volume so unless you were gonna mill .050 which will not be cheap
because a machine shop would have to make about 20 passes w/the cutter.
Plus the deck surface of the casting would get thin and the intake probably
wouldn't line up well either. My vote would be for the 243 heads. IIRC you'll
have like 10.5 : 1 comp with a cleanup cut .007-.010 off the 243s and GM
mls gaskets.
Also cam lift isn't what causes PTV issues...it's duration. Depending on how
much the heads are milled, the gasket thickness, and piston type (flat or dished)
most people have no clearance issues with 230 to 234 duration @ .050 cams.
Always check to be sure especially when in the 238 and larger range.

WS6tx

iTrader: (25)

In for the answer too... I see 317 heads selling all the time for like 100-150. I'm A power junky on a tight budget. Although mine would be goin on a stock bottom end 346 ls1. Let us know.

95FbFormula

iTrader: (25)

They both flow the same but the problem is the more u mill the less u flow and even if you took them down to 66cc which I think is max you would essentially be putting ls1 heads on it I would get the 243 ls6 heads and save the truck heads for boost I'm cheap so I just bought 241 ls1 head to bump compression on my lq4

Jason 98 TA

iTrader: (4)

What camshaft are you planning on running? This will give us a idea of what p/v your going to need. We mill for customers for $75, that's a pretty typical amount.

rennat_2006

iTrader: (10)

Honestly I don't know yet. I had a 327 that was built with a big cam and all the other supporting mods in the car before this and peak power was at like 5700rpms. I'm planning on putting the ls6 intake manifold on it also with a set of long tube headers, full 3" exhaust.

The 327 sounded awesome at idle and was a screamer when you nailed the go pedal and that's what I want here too.

What would you suggest?

CHADMACK282

get 243 or 799 heads get them milled per cam and that will bring that LQ4 to life. That higher CR makes that motor a different animal right off idle The guys at TSP took care of me for reasonble rates and quality products. obviously you also need springs, pushrods, and tune also.

rennat_2006

iTrader: (10)

Yeah but I wanna keep it running on pump gas, be able to drive it when its 100* outside, and I don't want to have to flycut the pistons right now

zachplank

im looking in to the same thing atm got a stock lq4 putting it in my 99 z/28 m6, trying to figure out what heads and cam to go with, torquer v2 seems good for dd/track every now and again, and ls6 heads seem to be good but its gotta be drivable too, any one have this setup, anyone know what cr ls6 heads on lq4 will be and if the tv2 will have ptv issues ?

rennat_2006

iTrader: (10)

I went with 799 heads milled .010 and was told a torquer v3 would fit without ptv issues.

I ended up going with a custom cam, cant remember specs off of the top of my head though

Pachuco SCT

What do you mean milled per cam? I want to run a btr stage 2 227/234 cam on my lq4 with 243s but I want to mill them hopefully to 62cc. I wanted to see if anyone knew if I would run into issues.

G Atsma

CHADMACK282 hasn't been here for over 9 years.