Hello all...
Well I've been looking all over (searching) to try to find out how much power the 5.5 gen Maxima (specifically the 4AT, but 6 speed as well) loses from crank to wheels... There are so many different claims that I don't know what is accurate. The majority of opinions have stated that it's somewhere around 20%... Maybe more. Is this correct?

 

20% of 255 = 51. That leaves 204. So...maybe?

 

I've seen dynos as low as 190 WHP on a 5.5 gen.

 

To calculate the loss you have to start with an accurate starting point. I know, back in the day it was believed that our engines were overrated on HP and really only produced 240hp, not the 255 claimed by Nissan.

And the 02-03 4AT dyno's between 190-200 whp. So do the math.

Here's a thread about the underrated thing:

http://forums.maxima.org/5th-generat...thread-15.html

 

Didn't consumers go after Ford for the Mustangs not making advertised power?

 

Yup on one of the Cobra's if I remember correctly, and they won.

 

Nissan should give us all a set of Cattman headers to make up for it.

 

Agreed.

 

That's pretty close 202-206 whp

 

every car should be advertised by its wheel hp, not crank hp... the engine produces 255hp, GREAT! you only get to feel 80% of it. not so great. plus, hp sells cars anyway. torque wins races.

 

Ugh, I hate that saying. Check out my post in the tl vs maxima thread reguarding torque and Horsepower.

I heard those tractor trailors are pretty quick, they have upwards of 1000 ft/lbs of torque

I fully agree that cars should be rated based on their wheel horsepower. They just use crank horsepower as a marketing ploy. If every manufacturer used wheel horsepower, then all would be good, as different drivetrain layouts have different losses (awd, rwd, fwd).

 

Depends on the DYNO.

 

The margin of error between various dynos is smaller than the total loss from the drivetrain.

 

No, I meant more as in TYPE of dyno, sorry I should have clarified.

 

The only way you could definitively test your drivetrain loss is to go straight from a engine dyno to a wheel dyno that are very well calibrated to read properly, even then you're going to have fluctuations between what each dyno reads.

I would take a wild guess at 17-20% drivetrain loss on a FWD auto, though.

 

Don't the auto makers have a margin of error that is allowed regarding horsepower?

 

Yeah, 15-20% sounds about right for a FWD auto. Maybe 12-18% for a manual transmission.

Rear wheel drive may be 18-22% and all wheel drive is probably like 22-30%.


This is just my wild guess.

 

LOL I was just waiting to get flamed for that statement... and yeah they would all be different, but that's what we automatically assume anyway, right?

 

Come to think of it, every vehicle should be rated in Horsepower/Pound.

That would be much more useful.

 

That's how motor trend rates their road tests.

 

i believe it was the 99 cobra's that were in question. people were reporting that brand new GT's and Cobra's were neck and neck at the dyno and at the track.
if i remember correctly i think the was a TB recall for that year. rumor was that's why there wasn't a 2000 cobra and there was a 2001. supposedly they went back to "fix" whatever issues were wrong with the 99's.
situation was reversed however with the "terminator" cobra's. they were rated at 390 but were putting down 370-390 bone stock! which would translate to around 430 at the crank.

 

 

Why does it matter? Not tryna be smart about the question but I'm just curious

 

If any of you rookies had been here back when, we (A33B owners) just about class acted Nissan for said Altima 240/Maxima 255/ Pathfinder 240 HP values ..

 

HP is a measurement of torque, so maybe they should advertise torque.

 

x10^e10

 

WOW....

I agree with NMexMax

 

:metalmax: