L92 HEADS l76 intake on LS1?

**schrysler** · 12-14-2006, 12:09 PM

Ive seen L92 heads and L76 intake work with a Ls2. But will it work with my LS1? I eventually want to go to an LSX block. Will this work or is it just wishfull thinking. I know the intake and heads will work well together but just dont know if it will fit on the block. If it will, how good do you think the set up is. On ebay I can get them both for about $1,100.00 plus shipping sounds like a good deal but will it work?

**Toes** · 12-14-2006, 12:17 PM

nope...

**schrysler** · 12-14-2006, 12:46 PM

why?

**mrr23** · 12-14-2006, 02:47 PM

yeah tell me why as well. after all ,the LS1, LS2 and LS6 are the same except the LS2 has a larger bore.

**9T8W66** · 12-15-2006, 06:57 AM

You need a minimum of a 4" bore to use those heads.
6.0 or bigger only. It sucks but thats the truth.

**mrr23** · 12-15-2006, 07:10 AM

again, why? there are plenty of people using 6.0L heads on LS1 engines. need to be more specific.

**12secSS** · 12-15-2006, 07:25 AM

Because the larger valves (and angles) of the L92 will smack the cylinder walls of bores smaller then 4.00". Those heads are designed to work with 4.06" bores ideally. Typical 6.0L (LQ4, LQ9) heads have smaller valve then the L92, I believe they are the same size as LS1 valve sizes ... hence why LQ4 and LQ9 heads work on bores smaller then 4.00". The LS2 uses 243 (LS6) heads.

**9T8W66** · 12-15-2006, 07:35 AM

The L92 Heads have different valve spacing and bigger valves.They also use an offset rocker arm but I'm don't remember which one off the top of my head.
They won't work on the smaller 3.90 bore of an LS1.The old Gen III heads have all the same valve spacing and work on 4.8's 5.3's 5.7's and 6.0's
When they designed the new Heads GM new they could increase valvespacing and therefore put larger valves to increase airflow, This was because they were going to 6.0 and larger displacments in the trucks
The L92 heads are similar to early prototype LS7 heads but it is still a truck head that's why it's so cheap.

**schrysler** · 12-15-2006, 08:08 AM

Is there anything out there for the LS1 that would compare to those heads and intake for the price?

**ibanez7** · 12-15-2006, 10:23 AM

as stated above you need a 4" bore minimum.

blocks to bore
ls1, ls6

blocks it bolts too
6liter iron block -great block low cost
ls2
ls7

the fast 90mm intake with a machined ported ls1 heads w/upgraded valvtrain is close to cost to the l92/l76 combo, just alittle more pricey!

**mrr23** · 12-15-2006, 06:21 PM

yeah, i got the answers today at PRI. the intake valve is 2.150". this will hit the cylinder on a 3.900 bore. i'll have some pics up shortly.

**z28misfit** · 12-21-2006, 11:53 AM

Just pick up a copy of the new GMhigtech magazine. It will tell you what you want to know.

**djvaly** · 01-15-2007, 02:53 PM

what is the gain due L92 heads on 402 ls2 forged block?
I am swapping ls1 to ls2 402 stroker, so if I were to use L92 rather than Patriot stage III would I be better off? I know L92 are cheaper but what about the gain.. 30-40rwhp? or what>?

**z28misfit** · 01-16-2007, 11:40 AM

I would say they are deffinately worth the switch over. The ports are designed better than an LS1 head, even ported ones as far as I understand. If you want to make sure you deffinately have a better head, I believe Livernois Motorsports offers a cnc'd version of the L92 head now. Not 100% sure but check their website out.

**djvaly** · 01-16-2007, 11:42 AM

Originally Posted by z28misfit

I would say they are deffinately worth the switch over. The ports are designed better than an LS1 head, even ported ones as far as I understand. If you want to make sure you deffinately have a better head, I believe Livernois Motorsports offers a cnc'd version of the L92 head now. Not 100% sure but check their website out.

cool man, I'll do that research.

**Bob K** · 01-17-2007, 03:47 PM

I dropped off my L92 heads at the shop on Sat. He's going to mill them .030 to make the chambers 65cc, clean up the bowls and exhaust ports.

The L92 heads and the L76 intake (90mm throttle body) cost me $1380.00 delivered. I spent another $500.00 on springs, rockers, stands and bolts. The head work will cost about $650-700.

I expect to get about 500rwhp and 500 rwt with the above heads, a custom cam and a SLP 402.

Should be very interesting.

Bob K.

**djvaly** · 01-17-2007, 03:57 PM

Originally Posted by Bob K

I dropped off my L92 heads at the shop on Sat. He's going to mill them .030 to make the chambers 65cc, clean up the bowls and exhaust ports.

The L92 heads and the L76 intake (90mm throttle body) cost me $1380.00 delivered. I spent another $500.00 on springs, rockers, stands and bolts. The head work will cost about $650-700.

I expect to get about 500rwhp and 500 rwt with the above heads, a custom cam and a SLP 402.

Should be very interesting.

Bob K.

I am getting 402 stroker block, G5X3 cam custom grind, and some good Patriot stage III heads or L92 modified like u (put the heads on a little later due to stock tranny still that can't handle over 450rwhp) and the mechanic said 490-500rwhp tuned..
yes.. that's cool, make sure u have the 12 bolt rear end, and decent suspension work done (shocks, SFC) too.

**FASTSS** · 01-18-2007, 08:45 AM

Originally Posted by schrysler

Is there anything out there for the LS1 that would compare to those heads and intake for the price?

In aword no. These heads are great as they come. The cam requirements for them are SO much different than any of the ls1/2 stuff though. I would personally not even consider a cam with less than 12-14 degrees worth of split.

**z28misfit** · 01-18-2007, 11:56 AM

Yeah I would imagine with those heads you can run a pretty healthy cam with excellent power. I believe in GMHPT, they said around 700hp naturally aspirated with the right parts should be no problem with the L92 heads and the right intake of course! Don't qoute me on this though, just going by memory.