Venkman

iTrader: (4)

let me guess, your block casting number is 12561584...

u8dusst

And what does him having the ls6 BLOCK have to do with anything?

And are those numbers in your sig are just with a lid and loudmouth?

MarineBlue03GMC

yea those numbers are high but might be possible!

This past weekend, at morgan motorsports in Reseda,CA, I saw a 02 Z28, with an air filter, exhaust, and a few other small mods, make 350+ hp to the wheels.

One question how are you guys correcting hp? Any internet links that have such a calculator? What are you correcting for, RWHP too flywheel HP?

Venkman

iTrader: (4)

Thats just it, its not the LS6 block. The LS6 cast number is 12561168. Ive seen this motor (12561584) in a few 01's and 02's and they all fly. I dynoed 357, the maker of this thread did 355, and a friend trapped 109 with lid and cutout. Theres something about this motor that will outpower a LS6, with LS6 heads and cam added, and i dont know what it is.

Vents

iTrader: (9)

um, i really dont think that there's anything diffrent about these blocks other than the casting numbers. i've got a friend w/ an 02 full on SLP ss car. he put down 335 bone stock and i mean right off the showroom floor bone stock.

aside from that, my car in stock form went 13.3 @ 109 on street tires. lid and a cutout. so what? it's a 99 even...

all this hype about LS6 blocks is a crock. it's just a block, and technically the only real diffrence is a few bits of casting flash we call an id number.

MarineBlue03GMC

not that this is part of a LS6 short block BUT the LS6 factory heads have sodium filled valves. Has anyone tried using sodium filled valves? Any point or is this just a minor gimmicky mod?

TWS

iTrader: (63)

Kinda late jumping in, but I can vouch for Jason's numbers. I know him and his car and have held both dyno sheets in my hands.

Also have to echo what was said about Colvin's where the dyno pulls were performed: they've been around a long time and have a solid reputation.

FLYNLO

On any particular day due to ambient conditions, the actual horsepower may vary. For example.....if you dynoed your car at sea level on a 60 degree day, let's say the dyno was 310rwhp. Now if you took that same car to Denver(5300 feet above sea level) on a 90 degree day, it would put out some hideously anemic numbers due to elevation and temperature(also referred to as Density altitude). So the Society of Automotive Engineers(SAE) has come out with a standard atmosphere(just some sort of reference). If the ambient conditions are different from that standard, then the dyno programs will correct for non-standard conditions. So in our little scenario, theoretically speaking, the corrected numbers from the first dyno should be the same as the second dyno....after the correction. The actual power generated at the dyno roller would be very different. Make sense???

Also as far as the sodium filled valve stem question, it is not gimmickry. If you lower the rotational mass of your engine, it will turn more freely and therefore develop more power. Also, due to the valvetrain being lighter, it allows more stability of the valvetrain(re:valve float) which allows the LS6 a higher more reliable redline of 6600RPMs.

Hope all this makes some sense.