Hey i tryed searching but didnt find anything im just curious what the actual crank hp is on the ls1 in my 2001 trans am, i know they are rated at 310 but being they dyno close to that stock i know gm's underrated the motors does anyone know what hp they actually are at the crank i would gues around 340

 

Generally speaking the 01-02's are around 350-360+ at the crank bone stock. It is not uncommon to see power variances with the LS1's.

I have seen A4's on a Dynojet put down between 288-300 RWHP, and M6's between 300-310, sometimes more. The general consensus is that the drivetrain loss is roughly 17.5% on the A4's and roughly 14.5% on the M6's.

 

FWIW, noone looks at hp at the crank, we look at what you are making at the wheels. also there is a forum dedicated to dyno/hp information just below here...

 

I think its closer to 15% for the A4 and 12% for the M6 but there is no real way to know.

 

exactly, and who gives a **** about flywheel hp unless you just want to inflate numbers. the power at the ground is the power you have that is useable so why worry about anything else

 

well here at work everyone really isnt car guys and they have things like maximas and stupid **** and they say oh well ur only like 50hp more than me no big deal but they dont understand wheel hp to crank hp difrences, and im trying to make then understand that when they say that have 250hp they really only got around 220 so to stop confusion i can just say i got ex.. 360hp and to compare evenly sense there idiots

 

i can understand that one ahha

 

just say yea your right, lets race for lunch lol

 

yeah i know some guy that has a 04 civic ex i think an ex actually thinks hes better and likes to call my new car a POS and i just laugh and say stop talkin about your honda like that i know it gets u around slow but it gets u there lol

it amuses me some of the guys here are like how can u spend 13k on a used car with 50k miles when u can buy a new car for the same price and i try to explain that u dont get great handleing and 310hp or an aggresive look and sound for a 14k new car they just dont get it. he drives a chevy aveo and a corolla what can i expect

 

Yeah, around here most people dont know the difference between WHP and BHP. Just about everyone goes by factory ratings. Depending on who Im talking to and what were talking about, Ill aproximate the translations in my head.

You can calculate yours by taking your RWHP and dividing by .88 for an M6 and .85 for an A4. You might want to lower that number by .01 or .02 for a 12 bolt or neumerically higher than stock gears and or real heavy tires.

 

RWHP is the ticket, but crank HP plays a very important role as well.

Fuel consumption is a function of flywheel HP NOT WHP. It doesn't matter whether you're running that power through a high (13% loss) efficiency manual T-56, or a low (25% loss) efficiency drag race automatic drive train. The engine needs a specific amount of fuel based on flywheel HP NOT WHP.

On a side note, keep in mind also note that a pump's flow capacity is a function of discharge pressure. As the fuel system pressure increases, the flow drops off. This makes estimating fuel demands and setting up you fuel system more important on an LS1 because of it's relatively higher (58 psi) fuel pressure.

You estimate the fuel needs based on crank HP and brake specific fuel consumption (BSFC). For example on a N/A setup, 0.50 #/Hr/HP is usually used, and that's very conservative. A well-tuned N/A engine with efficient heads can run 0.45 #/Hr/HP.

Let's assume for a second a LS1 that makes 500 HP at the crank.

500 flywheel HP x 0.50 #/Hr/HP = 250 #/Hr

Gasoline weighs approx 6 pounds per gallon; so you need 41.7 gallons/Hr = 158 liters/hour. Add 20% for return flow in a recirculated system, and you get 189 liters/Hr. For a blower or nitrous application, use 0.55-0.60 #/Hr/HP.

And BTW, you can determine drivetrain loss to a mathematical certainty. You just need to know the power the motor makes on a engine dyno and the power your car puts down to the ground on a chassis dyno. I have seen over a dozen posts and personally witnessed several people who have had their engine dyno'ed and then put the same motor in their car and then put it on a chassis dyno.

The stock A4 and 10 bolt averaged right around 17.5% loss and the T-56 and 10 bolt combos showed an average of about 13%. My orginal posting of 14.5% was incorrect.