Just got my 05 dyno tuned. I just had the L92/L76 head intake setup installed. Already had a 228/232 cam and headers, exhaust and cai. I also have 3.90 gears.

What kind of numbers are others getting out there with a similiar setup on a LS2?

 

My mods are in my signature....GREAT #'s

 

Thank you! Very nice #'s yourself.

 

We're pretty close! Mods in sig. I have stock heads, FAST and a little larger cam.

 

Great numbers!

My cam is larger than yours. Stock heads and compression. Auto A6.



Mods are in the signature.

441rwhp & 386rwtq | Kooks 1 3/4,cats, x-pipe | VR,160 t-stat | Cartek 3X cam |
Rt.66 catback | Ported fast90 | ASP underdrive pulley | 3200 Vigilanti converter |
| Stock 2.56 gears | Stock heads and compression |
Cartek tuned and track tested.

Best 1/4 (ET)60ft 1.65 - 11.132@125.03mph...60ft 1.64 -11.133@124.84mph

Best 1/8 (ET)60ft 1.64 -7.172@98.08mph.......60ft 1.65 -7.181@98.38mph

 

05 MN6, L92/L76 stock heads, 440/405. Baseline bolt on was 378/366. Do you have the stock L92 heads?

 

So you gained 23rwhp and 24ftlbs of torque with the bone stock l92 heads and intake bolted up? Just out of curiousity I wonder what a stock set of ported 243 heads and a ported FAST would have added? I always here the ported FAST is good for about 20rwhp in the mid range.

 

My dyno sheet above shows a ported FAST vs. ported stock intake, both on stock non-ported heads.

 

Here's my 05 LS2 mn6 with stock heads, FAST, 1 3/4" long-tubes, cat-back and Comp Cams 230/236 .608/.613 113 lsa cam.

 

'05 Z51 6MN, stock heads, Mods:

228/232 114LSA .598/601.
springs, pushrods
1-3/4 Kooks LT, 3" x & mids
u/d pulley
Ported FAST
Vararam & spacer
160* stat

 

in 3 days, 2 head swaps were done on my car...on the graph you will see the L92/L76 setup and my Trickflow 225 setup...these numbers are through 4.10 gears

L92 and L76 462/423
TrickFlow 490/442

 

Great numbers.

 

The heads were milled to get the compression up to 11.2:1. Stock gasket.

 

The dyno sheet is the difference with the tune. Both are with the L92 heads. The first run is what it did in the door. The higher numbers is with the tune.

 

The Ported FAST must make a big difference. Before I did the L92 heads I had almost the exact same mods as you. My cam is almost the exact same as yours, dynatek Lt's, u/d pulley, ported intake, 160 stat, B&B bullet, cai.

I dynoed at 425rwhp with these mods.

I am now at 453rwhp. So the L92 heads added 28rwhp. ( I also added 3.90 gears which they say will drop the dyno number by about 10 rwhp.)

 

Very nice!

 

I had DTE do a L92/L76 plus Dynatech headers, pulley, K&N, and Corsa exhaust on my 07 MN6. I don't know the cam specs but it's pretty mild. I went from 353/357 to 460/432.

 

I can't say for sure, but I certainly believed the ported FAST was the culprit. I did it myself w/ some guidence from Spin, & will admit I went all out on smoothing all transitions, removing any extra material, etc. to as close to perfect as possible. I think there's also a perfect combo of mods tuned to perfection. I just know when I look at cam only LS2s, mine, even w/ only a 228/232 cam, stacks up against the best. Note most of these guys are running substantially bigger cams.

 

Careful.....the experts will think you are 'poo pooing' the precious L92's.

Same cam and no other changes it appears to me that you shut the case down....the L92's are a cheap head that is only good when you look at the cost and use a medium sized cam. Port them and turn them into a 2k head and the AFR's, ETP's and Trick Flows run away with the show. Bigger cams need lots of fly-cutting which isnt free and lessens the value.

What I would really like to see is someone swap out the Ls3 heads with the trick flow 225's or bigger and see what the bigger bore does for the best of the cathedral heads.

For the $400 heads, 280 for valves and 300 for springs, the l92's are a good alternative with a medium sized cam but lose the value when you up the ante with porting and flycutting costs. I have seen some impressive results from RPM and DTE but both use secretive builds and arent the norm. Since not many have duplicated the 500rwhp results on a LS2 with ported L92's, it makes sense that a good set of trick flows that repeatedly yield 500 to the wheels are more likely to be had with the cathedral heads if you dont have the magic cam already in the car.

The highest I have gotten to date with the bone stock L92's was with a 230/236 XFI cam on a 114 LSA. It made 477/437 through 4.10's.

The real story is the 4k rpm torque with the best cathedral heads. This is often the result of good compression which is difficult at best to get with L92's. Be prepared to flycut for anything over a 224 cam with ideal compression. ETP and trick flow can use a 236 cam without cutting into a piston.

The OP's results are good and for a street car the power is likely more than he can use on street tires.

One tech point is that you always exhaust a thinner gasket thickness before you mill a head. Stock gaskets and milling hurt flow compared to less milling and a thinner gasket. You could have used a .040" gaskets and milled 1/2 as much for the same compression preserving some of the flow lost with the milling. Thinner gaskets also help with octane related sensitivity by reducing the quench area.

 

My number are similar on a dyno jet dyno. I have a slightly smaller cam and the afr 225's. Im also an auto with a stall which eats horse power. The true numbers are your track times. It sounds like you have a nice ride though. So have fun and be careful!