[QUOTE=AU N EGL;1565763820]380 is pushing it.

a 2002 or newer LS6 motor on 100 octane race gas, stock parts though from Intake though to the cats, then open exhaust could be tuned to 380 rwhp.

Not an a 2001 or older engine.

Bolt ONs help some what. any great single CAI over stock makes a difference.

LTs yes makes a different

x-pipe with free flowing open exhaust - YES

Mufflers or cat back - nope those are just for sound

plugs and wires - nope the AC Delco are still just about the best plugs and wires. Most racers still use these

any special fluids - nope

Changing to a dry sump oiling system - YES but very expansive.

the TUNE is the biggest source of more HP and TQ


unfortunityly some shops will make a dyno reading almost anything they want to get higher numbers and happy customers.

So take dyno numbers with a grain of salt. Dont believe what you read in advertising. "THIS PART will ADD 50+ HP to your Corvette"[/QUOTE I thought from 01 to 04 had the ls6 intake manafold,What else went to ls6 in 2002.I thought they were all 350 hp from 01 to 04.from 97 to 2000 they were 345 hp.Or am i wrong...

 

The "rating" didn't change much from 1997 to 2004 but there were major block, intake, cam and head changes between 1997 to 2004 on the "base" motor. While the 1997 may have put down approx 300hp to the wheels, the 2004's usually put down about 10-20hp more, which means that GM underrated the later models.

 

The 02s and newer have the LS6 block. Better oiling gallies, better cooling chambers, stronger head bolts then the LS1 blocks up through 2001.


LS1 block engines are still very very powerful blocks. If you are looking for that last 2-5hp, as we all know those last few hp takes everything possible to get.

 

I believe that the 380 rwhp is high to me. I just had my 01 A4 at HPE in Houston, Tx. I have a Vararam, changed Plugs, wires, ported the TB added Kooks Longtube Headers with off road X-pipe with a B&B catback exhaust and I dyno/tuned 415 fwhp and 335 rwhp on a Dynotech machine. I just don't see how an 02 model can get 45 more rwhp with the same mods unless the numbers are exagerrated. But I have heard of even wierder things before, so who knows.

 

Maybe I am not following you here, but don't you only calculate hp through accelleration? And aren't the parasitic factors involved in a 4th gear run on the dyno exactly those that are involved in accellerating the car at any speed, although changing with each gear? And therefore the reason for running the dyno in the first place?
I don't think lightening the rotating drivetrain mass is going to result in a theoretical loss. It will be an actual loss that is born out in every dyno that involves a significant mass change from the flywheel back. If you are not accellerating mass, you are not changing the frictional loss either, so on the above load dyno, the measured frictional loss would only be a valid constant number for the one load RPM but would otherwise have it's own power curve.
I can understand frictional loss due to the rubber on the drum, gear teeth contact, and fluids under pressure (which a/t dyno results clearly underscore), but not how these factors would be a significant increasing drain as power increased. Wouldn't they be more affected by RPMs as presumably the heat and friction in a max 5500 rpm powerband is far less than if everything spins to say, 6500 RPMs? I have never seen any data to support this. BUT, if you can lose 10hp going from a 110lb rear wheel and tire combo to a 135lb combo, what would you gain going to a 0lb combo?
I would speculate the weight of the drivetrain in a stock C5 is maybe 90% of the power loss. Really a 45hp tax as a starting point. A figure around 15% would be accurate on a stock engine but only the frictional loss is curving up and this following the separate characteristics of the driveline fluids, the tire construction, and the various gear teeth based on their composition and contact configuration. It would be as linear as any other power graph, but independant of the driveline weight, which would be a dropping percentage of loss as power went up. So the 45hp lost to the mass of the stock system is a plummeting percentage as power is doubled, and the frictional loss follows it's own path. Unless one can prove that most of the first 50hp loss is frictional, then the whole concept of a percentage of driveline loss is inaccurate.
I think

 

The only way to get close to and over 400 rwhp is with a head and cam combo. a decent cam, not a baby cam. Plus a few other things, CAI, LTs TB and tune.

 

I'll add my 2 cents here.

Horsepower measured at the flywheel does not take into account power lost to accelerate the drivetrain and the wheels/tires. All the weight has to be moved and according to the laws of physics it takes energy (force) to do so.

BTW, what is actually measured is torque. HP is calculated using a formula based on torque. By definition, the HP and torque figures should be equal at 5252 rpm.

At the end of the day, rear wheel torque (rwtq) and rwhp are what count as that is the power available to accelerate the car.

I happen to have an LS1 motor, which I am modding (with the help of my brother), and hope to get somewhere in the neighborhood of 420 to 450 rwhp. I am doing heads, cam, ls6 intake, headers, and Z06 Ti exhaust among other things.

Given the weak cam of the early C5s (mine is a 99) I can't see getting to 400 rwhp without a cam change. My car is a 6-speed.

 

FYI here is a link to a 398 rwhp car I was dealing on last year. The power mods give a good idea of what is required. http://forums.corvetteforum.com/show....php?t=1668225

 

What I've highlighted in red is what I was conveying. If you make the driveline assy (including wheels/tires) harder to spin up then you are essentially LOSING RWHP because it takes HP to accelerate mass.

Go run your car at the drag strip with stock wheels and tires, then go slap on some wheels and tires that weigh 3 times as much. Guess what the outcome is? That's because you have ate up some engine HP spinning up those heavier wheels and took HP away from accelerating the CAR.

The statement in red is not true. Frictional losses in the driveline are proportional to load -- this is true for any type of friction; it’s a basic engineering principle. If you have high loads at a constant engine load, you will also have high driveline friction and will lose more and more HP as the level of HP is transferred through the driveline is increased. The frictional HP losses through the drive train at WOT at 6000 RPM is going to be a lot more than the frictional losses at 6000 RPM with a 10% throttle opening (ie, low engine load = low engine HP output).

You need to study up on friction principles. If you put more load on something then the frictional forces increase proportionally in a linear fashion.

http://en.wikipedia.org/wiki/Friction

 

[
The statement in red is not true. Frictional losses in the driveline are proportional to load -- this is true for any type of friction; it’s a basic engineering principle. If you have high loads at a constant engine load, you will also have high driveline friction and will lose more and more HP as the level of HP is transferred through the driveline is increased. The frictional HP losses through the drive train at WOT at 6000 RPM is going to be a lot more than the frictional losses at 6000 RPM with a 10% throttle opening (ie, low engine load = low engine HP output).
My bad. Loaddyno .



You need to study up on friction principles. If you put more load on something then the frictional forces increase proportionally in a linear fashion.

http://en.wikipedia.org/wiki/Friction[/QUOTE]

Eep! High school physics! Correct again of course.

 

and why in many race cars we see Carbon fly wheels, carbon clutches, carbon fiber drive shafts, micropolisher gears in the trans and diff. All to lower the drive line friction. special gear oil and transmission fluids all to reduce friction and lesses drive line losses.

Even something as simple as an aluminum fly wheel reduces drive line loss.

 

Chad Knaus (NASCAR Crew Chief) was explaining how for a qualifying run at Talladega they put in a super low viscosity oil in the tranny and diff, and they put in the ABSOLUTE minimum possible .... all to get that 1 or 2 more HP by eliminating the gears "churning" in a heavier oil ....

 

driveline loss is not the same as friction, but friction is a non-trivial portion of driveline loss.

the primary benefit of a lighter flywheel is a smaller moment of inertia, secondary benefit is smaller mass. It has little to do with friction.

Though I do agree with the claim that friction is, for the most part, linear in load.

 

The general term of "driveline loss" is typically meant to simply mean "lost HP between the engine and rear wheels". It really consists of both frictional losses and intertial losses.

 

That's what I was saying I just don't understand why au n egl included a light weight flywheel in a friction statement.

 

Zero wt oil. Felt some Quaker state 0 wt oil. it was like there was nothing there