99-LS1-SS

I was wondering if the 6.0 truck heads flow better than the 5.7 heads right from the factory.
The reason I as is would it be any improvement in power to switch to a set of stock 6.0 liter heads from my stock 5.7 liter heads.

Boostaholic

iTrader: (4)

I'm also intrested in this

kickassT/A

iTrader: (3)

the LQ9 heads flow better, as they are a big chamber ls6 head. i dunno if it would be worth the swap though, seeing as you would loose compression. they work well in forced induction apps though.

xp3nd4bl3

Yeah, you'd at least want to get them milled. Or perhaps you could use a really thin head gasket. The LQ9 heads port really well too.

Ravenous T\A

iTrader: (12)

Thats what Patriot uses for there LS6 heads special, LQ9 is same design as the LS6 but with lower compression ( I think thats it, might of left something out)

Another_User

my understanding is that they are the exact same design as the LS6 head with a larger CC chamber to lower the compression ratio (agreement). Unless you are doing something to maintain your current compression ratio, or increase it I would not do it. Lower compression ratios have a lower volumetric efficiency at all RPMs and you will lose horsepower and torque across the band, and maybe gain a little way way up in the RPM band due to better flow...maybe. I would love to see a dyno chart, but I doubt you would like to see it. It would suck. I think the amount you would have to shave would be too much, which is why the head companied that use them fill up the extra space with some filler or weld or something. You could switch pistons though. Now if you are going for a blown application, yes they would work out awesome. But...you would probably still want to replace your pistons so you don't blow a hole in one (or more).

jrp

iTrader: (16)

and check my cam guide for the stock flow numbers.

ls6jimmy

iTrader: (2)

0.30 will give you 10:1 compression and you wouldn't have to modify your intake. And you could take as much as 0.70 but your intake would need modification's

LS1derfull

So would your pistons, extra valve reliefs. .070"off heads with any cam would come up shy. Do a search about 6.0 vs. ls6 heads because there is a intake port design difference. Someone has chimed in about this in the past, maybe Brian Tooley from TEA.

JZ'sTA

iTrader: (23)

Yo jrp I read the whole thing, no where did it show stock head flow numbers.

toxic99

I looked at your "cam guide" and I don't see any flow numbers, as in, head flow #s. If that is what you were refering to? I am trying to find stock head flow #s for 241s.

jrp

iTrader: (16)

lol, im a dumbass, your right. i though i put that **** in there but i didnt. was gonna make a head guide as well but never got around to it. anyway here it is:

http://ourworld.cs.com/jrpws6/heads+...ckheadflow.jpg

99-LS1-SS

Can you translate the columns for me?

L/D
Full CFM
Test Pres
Flow Pres
Corr CFM

jrp

iTrader: (16)

what the heads flow are the Corr CFM.

toxic99

Thanks for link JRP.

fast98

iTrader: (16)

whats the bore on a 6.0 stock?

jrp

iTrader: (16)

4" bore

marc_w

I could have SWORE that LQ4's (9.4:1, "regular" truck motor), and the LQ9 (10:1 Silverado SS, Caddy SUV motors) all use the same heads?

The compression from my LQ9 comes from flat-top pistons.

toxic99

LQ4s came with cast iron heads and aluminum. LQ9s came with aluminum.

jrp

iTrader: (16)

only the 99-00 LQ4's got the iron heads, all 01+ got the same 317 or 052 (i think) aluminum heads.