[autox02altima]

Someone posted these QR25DE dyno charts on the SE-R mailing list:

http://www.b15sentra.net/vbb/showthread.php?s=&threadid=16489

John
2.5S 5sp
ex 200SX SE-R owner

 

[Ry]

141HP....

 

[autox02altima]

Those numbers are to the wheels (not measured at the crank, like the manufacturer does), so you have to compensate for losses in the drivetrain. I've heard that front wheel drive cars usually lose 17% in the tranny. So the way I figure it, 141hp is roughly 170 to the crank, which is still 5hp short . . .

It could be due to it being a new engine, it could be that Nissan is still exaggerating hp numbers, it could be that the numbers weren't corrected for the atmospheric conditions. The debate on the SE-R list is whether the helical limited slips saps more hp than an open diff.

John
2.5S 5sp

 

[02alty driver]

not bad, not bad at all, now just wanna see it running past the civic si

 

[altypaul]

I have a feeling the 6 speed hurts drivetrain loss. It does in other cars. I would like to a dyno plot of a 5 speed and automatic 25QR25. I will dyno my car this winter sometime.

 

[Afty]

I'd like to see a dyno of the base SE-R vs. the Spec V. That would give us an idea of the difference between 5-speed and 6-speed.

 

[nismoalty]

actually the lost to the wheels are
closer to 20% some time even as high as 25%
very rarely does a car get 17%

so with the 20% loss its a 175p engine will be 140hp at the wheels
so thats a good run

 

[altypaul]

My automatic 2000 Maxima lost a lot more to the wheels. It went from 222 to 161 HP. That's a 25% loss.

 

[Afty]

Don't manual '00-'01 Maximas dyno around 188 whp? I remember seeing this number in someone's sig over at Maximas.org. If so, that's only 15% loss.

 

[nismoalty]

he might be running some parts on the car when it was dynoed
i dont know if that is correct than its a real nice loss to the wheels

but for the most part a 20% loss is reasonable
more is bad
less is good

 

[Ry]

Those numbers are to the wheels (not measured at the crank, like the manufacturer does), so you have to compensate for losses in the drivetrain. I've heard that front wheel drive cars usually lose 17% in the tranny. So the way I figure it, 141hp is roughly 170 to the crank, which is still 5hp short . . .

It could be due to it being a new engine, it could be that Nissan is still exaggerating hp numbers, it could be that the numbers weren't corrected for the atmospheric conditions. The debate on the SE-R list is whether the helical limited slips saps more hp than an open diff.

John
2.5S 5sp

I know. I'm over at b15sentra.net seeing people bitch about 141 WHP.... It's like, if you don't want your Spec V, I'll be more than happy to park it in my garage.

 

[hee1]

140hp is indeed very disappointing..regarding the fact that the nissan people advertise it as 175..

 

[nismoalty]

dude are some of u that dumb when maufactures make there horse power
claims its at the crank
when u do a dyno run it goes from the wheels

and u lose 20% of ur horse power to the wheel
ALL CARS WILL LOSE THIS AMOUNT
not just nissan u can take a ferrari and it will lose 20%( give or take a
couple %)
NO NUMBERS GIVEN BY MANUFACTURES ARE TO THE WHEELS

if u take the new corvette z06 (405 hp) it will dyno near 324hp
at the wheels see the diff

 

[Ry]

140hp is indeed very disappointing..regarding the fact that the nissan people advertise it as 175..

Get your self the QR25 motor and put it on an engine dyno. If it's nowhere close to 175 HP then you can be disappointed.

 

[hee1]

ok.. i tried not to say nething but...
NO SHIT! i know that companies don't use the HP that goes to the wheels. I was just saying that i didn't think there would be that much loss when i was expecting more like 15%.
don't be a dick

 

[Ry]

ok.. i tried not to say nething but...
NO SHIT! i know that companies don't use the HP that goes to the wheels. I was just saying that i didn't think there would be that much loss when i was expecting more like 15%.
don't be a dick

First gens have been consistently losing 18% through drivetrain. 15-20% is normal.

 

[stefx]

Honda claims 127HP at the crank on my 98 civic with the 1.6SOHC VTEC. I usually see 100-105HP at the wheels on dyno charts posted on the net. 20% loss.

140HP at the wheels for 175HP at the crank is what I expected from the SE-R Spec V. Nissan made no false claims at all and delivered what they promised.

 

[bluebomberx]

Mine is definately quicker than the Mazda MP3 They have 140bhp. I still like that car though...

 

[niceguy]

Gotta love the drivetrain loss wars!! Anyhow, 15-20% is normal although the Civic Si somehow manages to get around 140whp out of a 160hp motor, around 12%, according to SCC's and others dynos. Anyway for you guys w/ auto's, figure close to 25%, my 93 has around 23% loss according to the dyno here in Memphis.

 

[so cal trucker]

Those numbers are to the wheels (not measured at the crank, like the manufacturer does), so you have to compensate for losses in the drivetrain. I've heard that front wheel drive cars usually lose 17% in the tranny. So the way I figure it, 141hp is roughly 170 to the crank, which is still 5hp short . . .

It could be due to it being a new engine, it could be that Nissan is still exaggerating hp numbers, it could be that the numbers weren't corrected for the atmospheric conditions. The debate on the SE-R list is whether the helical limited slips saps more hp than an open diff.

John
2.5S 5sp

I don't know if the dyno is of a SE-R which has 165hp, or the Spec V which has 175hp, the same as the Altima. If it's of the SE-R than the 170hp to the crank is a generous figure.