Anybody had their 2.5 Coupe on a chassis dyno?

[Jeff7181]

I've read a few things saying that the numbers for the 2.5 are over rated. Doesn't seem that far fetched to me... 175 HP and 180 lbs/ft taking a ~3400 pound car to 60 in about 7.5 seconds. Sounds pretty realistic, but I'm wondering... have any of you that have started doing performance mods put the car on a chassis dyno for a baseline? If so, what kind of numbers did you get?

[Hussain]

according to Nissan, the 2.5 with manual transmission is 3,052 pounds and the 2.5 with CVT is 3,095....... the 3.5 is 3,205 manual and 3,271 CVT. so both are less then 3,400

http://www.nissanusa.com/altim....html

[Jeff7181]

Ok... so... you haven't had one on a chassis dyno?

[Hussain]

no not yet (i have the 3.5 tho), my friend was taking his mustang to get dynoed and told me to come dyno my car too but i'd whether spend that money on buying performance parts and then later take it to get dynoed. the 2.5 does have some power though. i never test drove the 2.5 A/C but my mom had a 2005 2.5S that was stick shift and i would take it up to redline almost everyday (she did the same too lol) and it got a lot of people by surprise, they didnt expect to get beat by a Altima... the A/C is smaller so it should be even faster

[Jeff7181]

Yeah, for normal driving it has plenty of power... I'm just curious how close it is to those numbers since a few places are saying it's probably over rated.

[generic808]

HP ratings from the manufacturer are listed as HP at the crank. If you put your car on a dyno, you'll get a much lower number, which would be the HP at the wheels. If you're car is listed at 175HP, I'd say a WHP rating would be somewhere around 145 give or take a few. The power lost through the drivetrain, engine, wheels, transmission, driveshaft, differential, and axles, can greatly affect the amount of the powertrain loss. You'll usually see a loss of about 15-20%.

[Jeff7181]

Sure, but a few reviews I've seen say HP is actually more like 160, which would put HP to the wheels at around 130... give or take.

Honestly, I don't know what they're basing it off... maybe the 0-60 times or 1/4 mile times. I can't imagine anyone who's actually driven the car with a 2.5 in it would say the power is over rated... it's the "torquiest" 4-banger I've ever driven. At part throttle it gives the impression that it's a much more powerful engine than it actually is, in my opinion.

[generic808]

Sure, but a few reviews I've seen say HP is actually more like 160, which would put HP to the wheels at around 130... give or take.

Honestly, I don't know what they're basing it off... maybe the 0-60 times or 1/4 mile times. I can't imagine anyone who's actually driven the car with a 2.5 in it would say the power is over rated... it's the "torquiest" 4-banger I've ever driven. At part throttle it gives the impression that it's a much more powerful engine than it actually is, in my opinion.

Where did you read reviews saying the 2.5 has only 160HP? The new SAE HP rating is more strict so ratings are actually lower than they were in previous years. If going by the old standard, the Altima would probably be rated higher.

"In April 2005, the Society of Automotive Engineers tightened rating guidelines, calling for all tests to include an SAE-approved witness as well as standardized conditions for fuel, airflow and engine load. SAE, whose procedures for rating engine output have been the unofficial industry standard since 1980, says previous criteria allowed automakers too much wriggle room. General Motors was first to adopt the new standard, announcing in 2005 that the Chevrolet Corvette Z06 produced 505 SAE-certified hp.

Studious car shoppers may have noticed that horsepower and torque ratings on some vehicles changed slightly in the past year. The 2005 Acura TL made 270 hp and 238 pounds-feet of torque, but the 2006 model is rated at 258 hp and 233 pounds-feet. Toyota's 2005 Sienna minivan made 230 hp; this year, it drops to 215 hp."

[TheBourneAltimatum]

no not yet (i have the 3.5 tho), my friend was taking his mustang to get dynoed and told me to come dyno my car too but i'd whether spend that money on buying performance parts and then later take it to get dynoed. the 2.5 does have some power though. i never test drove the 2.5 A/C but my mom had a 2005 2.5S that was stick shift and i would take it up to redline almost everyday (she did the same too lol) and it got a lot of people by surprise, they didnt expect to get beat by a Altima... the A/C is smaller so it should be even faster

i thought cvt's can't be dynoed. if you put it in manual mode and put it into 3rd or 4th it will downshift to first, and regular mode would be even more confusing since the car will just stay at 6k after you floor it

[rjdmmfl1]

Studious car shoppers may have noticed that horsepower and torque ratings on some vehicles changed slightly in the past year. The 2005 Acura TL made 270 hp and 238 pounds-feet of torque, but the 2006 model is rated at 258 hp and 233 pounds-feet. Toyota's 2005 Sienna minivan made 230 hp; this year, it drops to 215 hp."

Eric, along those lines, the Lexus SC 430 dropped from 300hp to 288hp.

My question to you is, does this mean the car companies were "inflating" their actual horsepower numbers?

[MagicM]

Funny thing about the new rating is a large majority of the Japanese/German lost horsepower, while the american cars gained power.

[TheBourneAltimatum]

[Thread Jack][/Thread Jack]

LMAO i'm gonna use what you wrote in the image as my sig!!! sorry to what happened to your car jeff

[generic808]

Eric, along those lines, the Lexus SC 430 dropped from 300hp to 288hp.

My question to you is, does this mean the car companies were "inflating" their actual horsepower numbers?

Oh, most definitely! Especially Honda and Toyota. America is power hungry so the more HP, the better the sales. If you look at Nissan's numbers, they never really dropped off.

[Hussain]

i thought i read online before that someone dynoed an A/C with CVT? if i remember correctly they did but they said it was hard to dyno it (forgot the exact details). if not then is there a way to put it in some sort of dyno mode? like the C-class Mercedes-Benz. does anyone know about this cuz i thought i read you could but im not 100% sure

[Jeff7181]

Actually in manual mode you should be able to dyno a CVT just fine. The only time the computer will change the ratio from what you've selected is if you've asked it to do something that may damage components... for example, not shifting. It'll "shift" for you if you let it hit the redline in manual mode. Or not downshifting... if you leave it in "6th" and coast down to 25 mph it will adjust the ratio so as not to stall the engine. Also, if you're cruising in 6th at 45 mph it will adjust the ratio since that's not within normal operation parameters. However, if you're in 3rd and accelerate up to about 30 mph, it should not adjust the ratio at all if you floor it until it hits the redline.

*EDIT* Oh, and thanks for the sympathy. It's all fixed now, but I can still see the "scar" if I look down the body of the car. They matched the paint perfectly though so I didn't ask them to redo the metalwork.

[generic808]

i thought i read online before that someone dynoed an A/C with CVT? if i remember correctly they did but they said it was hard to dyno it (forgot the exact details). if not then is there a way to put it in some sort of dyno mode? like the C-class Mercedes-Benz. does anyone know about this cuz i thought i read you could but im not 100% sure

I believe it was Stillen who dyno'd the CVT when the Injen was released. Don't remember the details, but they couldn't get a good run with the VQ CVT and only came up with 22X HP or something like that.

[Hussain]

ok, this is going to sound like a stupid question but how much WHP does the 3.5se have? lol someone had to have dynoed it with a stick shift

[TheBourneAltimatum]

ok, this is going to sound like a stupid question but how much WHP does the 3.5se have? lol someone had to have dynoed it with a stick shift

245FWHP. this is from a member on NC. and then he put a fujita intake on and got 261FWHP

[generic808]

A +16WHP increase from just an intake? Well, this issue has been brought up and beatin' to death many times before, but I'll go ahead and give my .02 cents once again.

When the car was dyno'd, it was done in a controlled environment. Probably in a temp controlled room with industrial fans blowing on an open hood. Now this type of gain will NEVER be seen in the real world. Why you ask? Because how can you drive on the streets with your hood popped up?

People can believe what they want, but in all honesty, you WILL NOT see 16WHP with the install of an intake, and a regular short-ram at that. I know there are a couple of guys who swear by these dyno readings, but we'll let them believe what they want. You also have to factor in the 15-20% drivetrain loss, which would bring that HP reading up to 18-20HP. So basically, a VQ powered Altima would be pushing over 290HP off of an intake? I think not! I'd hate to see what these people would say about an added exhaust and header. Their Altima's will basically be pushing around 320HP!!

Too funny!

[rjdmmfl1]

A +16WHP increase from just an intake? Well, this issue has been brought up and beatin' to death many times before, but I'll go ahead and give my .02 cents once again.

When the car was dyno'd, it was done in a controlled environment. Probably in a temp controlled room with industrial fans blowing on an open hood. Now this type of gain will NEVER be seen in the real world. Why you ask? Because how can you drive on the streets with your hood popped up?

People can believe what they want, but in all honesty, you WILL NOT see 16WHP with the install of an intake, and a regular short-ram at that. I know there are a couple of guys who swear by these dyno readings, but we'll let them believe what they want. You also have to factor in the 15-20% drivetrain loss, which would bring that HP reading up to 18-20WHP. So basically, a VQ powered Altima would be pushing over 290HP off of an intake? I think not! I'd hate to see what these people would say about an added exhaust and header. Their Altima's will basically be pushing around 320HP!!

Too funny!

thanks for the response Eric... I always forget that the Lexus is in essence an American Car! Yeah Toyota owns Lexus, but lexus is only produced and sold in North America!

Also, the +16 whp gain from the fujita is comical, if nothing else. definately not gonna happen in the real world! I would say that in real world terms, you should be able to get a real world +16 ~ +20 hp gain from an intake/header/exhaust combo!

[generic808]

Also, the +16 whp gain from the fujita is comical, if nothing else. definately not gonna happen in the real world! I would say that in real world terms, you should be able to get a real world +16 ~ +20 hp gain from an intake/header/exhaust combo!

That's exactly what I said a few months back in one of these debates. Realistically, you'll see maybe a 20-30HP increase with a I/H/E combo (if a header becomes available). Slapping on a simple $200 intake will not boost you 16HP! If so, why wouldn't it come like that from the manufacturer. America is so power hungry that a 286HP car vs. a 270HP car is an easy sell. And all for only $200? Come on now.

[Mr. Music]

remember that the dealer, i mean... stealership would charge at least $500 for a $200 part...