92SC498GS4

Hoping for someone's opinion.

I know the GS stock was giving 300HP. I purchased a 98 GS400 with these mods: K&N High Flow Air Intake, Apexi Neo, Dragon T/C,Toyota 3.76 LSD,S&S Headers, Borla Axel back exhaust,TTE Front Lip Spoiler,L Tuned ECU.

As I stated, I had it dyno'd last weekend and it came back with a 251hp/250 torque reading. Does that seem like it may have been an incorrect tune and dyno?

Thanks in advance.

neegroy

iTrader: (19)

yeah the thing is our cars are RATED AT 300 doesnt mean it puts down 300 to the wheel. i think 250 sounds decent lol, considering you have all the mods done.

sakataj

iTrader: (182)

300 is crank HP btw NOT wheel HP so you make about 313-315 crank hp.... i dunno seems a little low to me for intake, neo, headers, exhaust (rest of the mods including the TC/LSD make no actual horsepower)


is neo tuned correctly? try fresh plugs/filter/oil and try it again

porn-adkt

iTrader: (37)

with your mods, you should be around 270-280

250 don't sound right

Hardrvin

You never specified the dyno or location and conditions at the time, plus any corrections they used. We are only guessing to say that's high or low.

92SC498GS4

I went to PSI Proformance in Lansdale PA

Run conditions 59.74 F.
30.10 in Hg
Humidity 24%
STD 0.98
Max Power 251.12
Max Torque 250.01

some additional notes...I kinda screwed the pooch is why I'd taken it there. I bought the car with the mods. I saw all the pretty lights on the NEO and like a newborn I had to touch it. LOL. Ended up having the car towed to get it dyno'd because I didnt want to foul anything else up. The guys told me that they had to do the calibration from scratch.

kdick91

There will be some power loss through the converter if the stall speed is any higher than stock. Did they use a wideband to tune? I can't imagine doing a correct tune without AFR. Especially with just a Neo.

92SC498GS4

I apologize for my ignorance, but I don't know what you mean, regarding whether a "wideband" were used or not.

92SC498GS4

I have another question, sakataj had suggested new plugs. What are my best options?

speedaddic

iTrader: (10)

being that this is 2012...I dont see why anyone would tune without a wideband.

Flick2JZ

X2 on this. Higher torque converters actually hurt horsepower on the dyno. I'm not sure what the percentage is but it seems to be pretty common for a car to dyno lower with a larger converter then the stock or smaller one. Yet it actually makes the car faster.

kdick91

There is more slipping the larger in the torque converter which accounts for the 'loss in power'. The car is faster because it allows you to be further in your powerband. From a dead stop, when you gun it, it only hit like 1800RPM (iirc). With a bigger (higher stall) converter, you will be at, say 2500RPM. So look at it as horsepower per MPH. More power at those lower speeds

And y'all say it should have been tuned with a wideband, but I have seen, several times, people tune with a narrowband. Or using a wideband post-cat :/

Rock-a-Lex

iTrader: (4)

I have all your mods you listed for years, use the best fluids and always maintain all drivetrain items. I have a 3000 stall torque converter. My best was 282whp / 267wtq...they may be off by 1 or 2 digits; I 've posted results and dyno charts a while back on here. Oh, and it was about 70 degrees out. I would look at everything ...you're about 20 - 25 whp too low. GL!

Rock-a-Lex

iTrader: (4)

Fyi, my car dyno'd only 243whp when it was stock.

mk2tmr2

iTrader: (1)

The difference from Dyno to Dyno can be huge. Was this a Mustang dyno? Or a Dynojet? Dynojet numbers are notoriously higher by about 10%.

If the car doesn't have a WBO2 properly installed, they probably just stuck one in the tailpipe which is not ideal. But any decent tuner can still tune a car that way. A *real* good tuner can put on an engine stethoscope and tune based on how the combustion sounds.

They may have tuned very conservatively. Tuning is a weird game to play. You leave power on the table if you think the car's owner isn't super knowledgable about his car and how things work. Better to be safe than have the guy blow his motor up in a month and come back blaming you for it.

At the end of the day, Dyno numbers are only useful for 1 thing - testing and tuning your own car. Use the same dyno with the same operator every time you tune and then you can actually learn something. Other than that, it's just a bunch of numbers that people use in ****-swinging contests and means pretty much nothing.