I had my 95 auto dynoed yesterday with a JWT ECU and a y-pipe(on a dynojet). This was my first dyno, so I don't have any way to compare horsepower gains. My best run was 156-157 hp??? This sounds extremely low to me, but the guy who did the test said that I am seeing a 20-25% loss due to my car being an auto. He estimated 210hp at the flywheel.(210 X .75 = 157.5) Is this BS? What do you guys think? I'm thinking about having it dynoed somewhere else for comparison.
The guy e-mailed the results to me, but I can't open them(there is a program that you have to download from dynojet.com to view them). I can't get it to work. If someone thinks that they can do it, i'll e-mail the results to you.

thanks

 

that is true autos due tend to loose more hp at the wheel then a stick

 

Yes auto's do lose more power in the drivetrain than a stick shift car, however I thought that stock 4th gen autos put down about 155hp stock. It's in someone's signature, I'm sure they'll post it on here. I think it was 155hp stock, not sure though.

 

Is an automatic less efficient than a 5-speed when the torque converter is in lockup mode? Is the torque converter unlocked at full throttle? Are dyno measurements made in an automatic gear other than 4th?

My Maxima is a stock 5-speed and I've never had a dyno measurement, so I'm unfamiliar with these details.

 

Would the VB Upgrade help the Drivetrain loss? like maybe drop 5% HP Loss due to drivetrain or no difference?

 

The dyno was done in 1st and 2nd gear. the results in 1st gear were ignored because the wheels are accelerating too fast(the dyno can't get a good reading). 3rd gear and 4th are not used for dyno purposes simply because you would be spinning the dyno rollers at over 100 MPH. Therefore, 2nd gear(roughly 45-85 MPH) is used.

It is much easier to dyno a standard trans because you can put the transmission in 3rd and accelerate at WOT from 1000 RPM to redline.

 

Dyno'd with a JWT intake and '96 SE rims and my results were 155.7hp/172.2tq.. I have an auto.

 

I think it was in 3rd since it was going over 100mph..

 

You are supposed to dyno a maxima in 4th gear. If you do it in lower gears the transmission multiplys the power. BTW this is a fact. I had my car 125MPH on the dyno and everything was working fine.

 

Hmmm, automatics are dynoed in THIRD gear, the gear closest to 1:1, 5 speeds are dynoed in FORTH gear, the gear closest to 1:1. There is little use to dyno in any other gear. The STOCK automatic should dyno at ~155 HP, 170 lb-ft. of TQ.

 

From what you all are saying, the dyno that I did in 2nd gear is innacurate and I should do it again in 3rd?

BTW, I had this dyno done at Dave's Honda Haven in Memphis(should have known better than to take my car to a Honda shop!)

 

Of course there is something wrong with your result. It should dyno 155HP stock. With your ECU and ypipe, you should get at least 165 at the wheels.
I say the people at the dyno shop dont know what the hell they're doing.

 

My totally stock 1995 GLE dyno'd at 152HP and 176 fl/lbs. Either the dyno operator screwed something up, or your mods are doing a lot less for you than they should.

 

theres an inumerable amount of factors that could contribute to poor dyno results, or results that arent up to par. it may not make much sense but two cars exact same year exact same options in two side by side dynos can dyno different sets of numbers. i used to work at a dealership we had about 200 cars on the lot at any given time , and some cars are just naturally faster then others. i cant give u a lengthy explanation because i dont know exactly why but ive seen it with my own eyes and driven the examples
-pete

 

The VB modification helps acceleration by making faster shifts. It does nothing to reduce slippage in the torque converter, and that's where the losses occur.

 

The VB modification helps acceleration by making faster shifts. It does nothing to reduce slippage in the torque converter, and that's where the losses occur.

 

I dynoed my 97 Auto SE a month ago with Stillen air intake, y-pipe and rear section exhaust. Dyno done in 3rd gear as I thought all were. Here are results:

Peak hp: 170.6
Torque: 189.1

If stock is 155 hp, then I guess my results weren't TOO bad. By the way, what the hell is a VB upgrade? I see this mod referred to everywhere, but I have no idea what it is.

thanx

 

VB = transmission Valve Body

 

www.mobiletek.com (or net?), Don's VB upgrade or check out level 10 trans.