HAte

does anyone read my posts? (OP) hahahaha

bhop42

iTrader: (2)

Buy an LY6 which already has the L92/LS3 heads, Fast intake, and a Pat G cam. Remove the heads and have them shaved to up the compression and have them ported. That should put you in range.

bhop42

iTrader: (2)

BTW, an Lq9 is a Gen 3 engine so you would find more responses in that section.

Stumped1215

iTrader: (9)

Defiantly do the lq9 over the ls6. Cubic inch will be your friend in meeting this goal.(not that it cant be done with a ls6)

The hp over the 346 will not be any thing huge but torque will be up quite a bit, and every little bit helps if you dont want to be disappointed in the end.
I would run the stock bottom end if I were you, but you could do a cheap rebuild with scat rods and a good piston.

speedtigger

iTrader: (16)

LQ9 here. Ported heads, small 226 cam and 2800 comverter. 7.20s @ 96 in the 1/8th at 3700+ lbs.

HAte

yes thats why im researching lq9s because i want to go bigger and figured itd be easier to make what i want to make to the wheels out of an lq9 instead of a ls6

and the lq9 gives me room to grow later. (i.e. stroker and or bored or boosted or blown)

for the record i dont mind about paying 2000 for aftermarket heads, thats why i made this post to find out whats gonna yeild best results without parts almost being at their limits.

was hoping for input from people with aftermarket heads and such what results, and also opinions on what brand or size head is going to be the best choice

Stumped1215

iTrader: (9)

From the research that I have done on aftermarket cathedral heads they are all basically the same. Some have a little better midrange or top end than others but we are talking very minimal differences here. For a 364 I would look at anything 215cc-235cc runner depending on how wild it is. AFR, TFS, PRC, ETP are all great choices.

Well I can tell you that right now I'm putting together a forged lq with trickflow 225s, yellow tera rockers, fast 92/92, 230/238 .618/.618, 11:1 underdrive pulley, kooks 1 3/4, 42 lb injectors, ect.

This is going into a true daily street car 3700 lbs hence the smaller cam for power under the curve.
Car has a A4 3600 stall so I'm not looking for a huge dyno number here(If I had to guess I'd say 460-480 on a dynojet), but my real goal is to dip into the 10's and possibly 9's later on spray.

I feel that cylinder head is one of the most over looked items in a build because of the cost associated with it, but if you want a good running setup this is not a place that you want to skimp on. A good cylinder head is where most of the power is at.

You should read this if you haven't already.The thread is fairly old so its much easier to do now with the bigger intakes and better deigned heads, but a great read none the less.
https://ls1tech.com/forums/generatio...heads-cam.html

slimbobaggins

I dont know about the rest of the ls world, but (at least according to ls1gto) the record holder for ls3/l92 heads with a stock 6.0 bottom end is 487 rwhp.... so I would expect you're going to fall somewhat short of your goal with them. Im not knocking on ls3 heads though...500rwhp with a 6.0 bottom is going to be difficult regardless. OP, if you make 500+, you're going to be squeaking it out

KCS

iTrader: (20)

What about having a set of GM heads hand ported?

You won't get the best results with a set of CNC'd heads that anyone else can get. Those heads are based off a port someone did by hand, and chances are that head porter kept plenty of tricks up his sleeve or has learned some new tricks since making that port.

Here are a few recommendations:
Greg Good
Curtis Boggs
Ed Curtis
Dennis Wheet

HAte

i agree 100%, many people over look it

stroking the engine isnt out of the question, just was going to see what # i could possibly make without a stroker..... i guess not too many people have built these engines, i thought there would be more build references.

slimbobaggins

Building a lq9 is no different than building a ls2. Hop on ls1gto.com and theres a plethora of na 6.0 builds. The majority of them fall short of 500rwhp

HAte

O intsresting,boggins,I just found a few lq9's on here makin a little over 500 to the wheels with stock bottom end and ls3 heads.......id like input from experience internet forum hopping doesn't warrent that. Thanks to everyone with good input so far

slimbobaggins

I only suggested stopping by ls1gto since you're talking about building a stock bottom-end 6 liter, and that's what the majority of GTO's had, so there's a lot of knowledge over there directly pertinent to what you're looking for.

I never said there weren't stock bottom-end LQ9's making over 500 to the wheels... but whether they have square port heads, or cathedral port heads, I think you're going to find perhaps 10% of stock bottom-end (all motor) 6 liter's make 500+hp, and 90% make less than 500hp, unless of course you're running race gas.

You said yourself:

Building a 6 liter engine that has a stock bottom-end, can run on pump gas, and makes north of 500rwhp without a power-adder is going to be difficult, and certainly you're going to end up "squeaking by" 500. If you add more cubes it's a whole different ball game, but that's not stock bottom-end.

low2001gmc

iTrader: (148)

l92 intake is dyno proven to make about 10 hp over ls3 intake. l92 intake can still be ported to get a few hp more.

ls3 heads best bang for buck and if you want a combo to build on and expand on such as a stroker in the future and dont mind spending extra money on $2-2300 heads, it would be cheaper to just go ahead and get stroker kit and use ls3 heads to begin with and be happier for less $.

some to think about.

i got lq9 and ls3 heads. self porting my l92 intake to use with fast 92 tb. looking at using eps 226-234, 598-602, 113+4 cam which pat g recommended. will be using harlan sharp trunion upgraded rockers and lighter ti reatiners. headers and all bolt ons. to go in a 72 nova project. unfortunately, lost my job, so project is on hold but in mean time porting my intake and then plan to work on the ls3 heads exhaust to improve flow. hoping for 465-475hp which should be plenty for the nova