Spartan built LS2 GTO goes *492RWHP/448RWTQ*
 

Before we go any further I'd like to point out that this car has 4.11 gears. In an IRS car that's a solid 20rwhp loss on the dyno. I don't really care about dyno games, but this is a solid 500++ rwhp car with a stock gear. Pulls were also made through the mufflers.

Anywho...

Details:

-2005 Pontiac GTO M6
-Stock untouched bottom end LS2
-Trick Flow 220cc "As-cast" cylinders heads worked over with A.I.'s TFS CNC program for the TFS 220's. A.I.'s work on these heads (and every other set) is second to none. Heads are 59.5cc.
-Spartan cut Cam Motion camshaft: 230/236 .6xx/.6xx 113+2
-Stock rockers with custom shim kit (made by Spartan) for TFS heads
-Custom length TFS Pushrods
-TFS .700 lift Valve Springs (Not my choice, but they were already on the heads)
-LS7 lifters
-Melling HV Pump, GM LS2 timing chain
-1 3/4 Longtubes, OR mids, Corsa Catback (Pulls were made through the mufflers)
-G-Force 4.11 Gear set installed in-house
-Unported FAST 90mm/Stock LS2 90mm TB
-Vararam Intake
-ASP Pulley
-Spartan COS Tuning (Street tuning only. No tuning was done on the dyno)
-Numbers are SAE corrected

http://i773.photobucket.com/albums/y...005GTODYNO.jpg


Notes:
-Big thanks to A.I. for the work they did on the heads. I'll leave it up to Phil if he wants to release pictures of the work, but it's top notch.
-This build was intended for "daily driving" quality driveability, and far surpassed our expectations. Lugging around town in 6th @ 1800rpms is no problem.
-I DO NOT SELL CAMS, and cam specs are done for in-house builds only.
-Shoot A.I. an email if you'd like details on their TFS CNC program.

Nice results, bet it's fun to drive around town...I'm sending a set of heads off to AI this week.

Very nice results on a mildish cam. Really looking at the rest of the build other than an awesome set of heads that is a very reasonable build. Didn't even need 1 7/8" headers.

Its actually pretty useless in 1st/2nd gear with the power and 4.11s. Kinda like simulated ice skating, but it was cool. :D

I saw this car in person trust me its a total sleeper

Awesome work! I rolled that cam & really appreciated that it didn't follow the current trend of ever increasing aggressiveness. It is quite mild relative to the cams most run these days. :)

I have another LS2 dyno w/ our CNC'd TFS head on an LS2 w/ a 230deg cam that I'll have to dig up and post. I bet yours would even pick up a bit if the owner wanted to pay to race the drum for a couple hrs, port the TB, etc., but in the end I prefer your approach & doubt he cares since it turned out so well. :)

Thanks Josh!

-Phil

It could probably use 1 7/8 at it's power level, but the owner of the car is very happy with the way it is now. With a bigger header and stock gears this is a 510-515rwhp LS2, but we're not chasing the dyno so oh well.

The TFS were ported due to circumstance. The car already had TFS 220's on it and suffered a Comp camshaft failure. Since the heads were off we decided to let A.I. work their magic knowing that we were going with a smaller cam than before.

We're happy with the result.

Very nice! I plan for a similar build with those heads, except with a fast 102, ms3 cam and stock gears. Still don't know if I'll do a 402 or just stroke my ls1 to a 383.

Thanks for the kind words Phil.

Reasons you listed above are why I continue to do business with A.I. We are not interested in internet hype or sticking the biggest stick we can get to fit. It's about the combination of parts creating a well working package. It's a shame that internet marketing for LSX parts as a whole has moved away from this style of thinking but we're slowing bringing it back.

I also don't like big square lobes that beat the snot out of the valvetrain. A nice smooth lobe will get the job done with minimal wear on parts and retain nice stability @ high rpm.

Great job, and good to see someone not chasing NUMBERS.

Impressive numbers

GREAT JOB Josh!!! Keep up the good work man!

Another great build Damian!! congrats!!

This GTO was in the shop the same time I was getting work done on my 04Z. The car is a beast and sounds fantastic. Josh does better than quality work and like I've said before, he treats his customers better than we deserve. If you listen to his advice you will end up with a LSx masterpiece that is better than you thought it could be.

Keep up the excellent work Josh and if I ever see that heifer in the SW 01Z I'll tell her the car makes her look fat and that a vert would make her look 20 again.

LOL at simulated ice skating...
 

LOL at simulated ice skating...

That's a nice powerband. Nice numbers!

Not trying a :hijack: but my car is a perfect example of not chasing dyno #'s. I have a built 402ci LS2 with TFS215cnc heads opened up to 4' bore and other secret work done to them by us. EPS custom grind cam, ported fast 90mm intake and TB, TH350 tranny with a 5000rpm PTC stall converter and a strange 12bolt rear end with a 4.11 gear. The car made 450rwhp on the dyno but has gone 10.39@129mph 1.41 60ft first time off of the trailer and the car is full weight @3540 race weight. This motor will only get faster as time goes on.
Dyno #'s don't mean jack!! Thanks

Bringing this back from the dead... Josh, what do you think AIs 220 program would yield on a 346 with a similiar sized cam (228/232 or 226/234) and LS6 intake?

Awesome numbers!!!

Personally, I think the CNC program for the 220's is best suited for the 6.0-6.2L engines.

For a 346, I like moving the air into the chamber as fast as possible. Look at the HCR 219cc 241 and the 218cc 5.3L heads A.I. offers. Those are the best bang for the buck for a stock short block 346.

The TFS/A.I. route is also not a very cheap route. Albeit effective, you're talking about an $1800 cyl head and $600 (not including to/from shipping) of CNC work. As seen on this car it's an effective program, but not necessarily for the budget minded folks trying to stretch a dollar as far as possible. But, if the funds are available I do believe that the TFS/A.I. combo is probably in the top 3 most potent cyl head combo's in existence for the LSX engine.

Hope this helps.