had my car dynoed on a Mustang Dyno!!!

[TimeLord]

I must have one of the quickest 298 RWHP Z28s in town,I have trouble making any sense from the graphs also[no scanner,sorry].

My car's raceweighs is 3700 LBS and it traps 12.3s at 112?

Very confuzzled!!

A few years ago[before the 1.6 RRs] I dynoed 352 RWHP on the DynoJet and ran 12.9s.

[Z Ya Later]

Yeah, the Mustang Dyno's are also very "conservative". I wouldn't trust those numbers to be accurate.

[Kevin - Blown 95 TA]

Dynos are good for tuning if they have a good o2 sensor, and they are good for before/after comparisons, but they can be innacurate for a horsepower evaluation, if you want a high hp reading, you might have to go to a few different dynos until one says what you want to hear.

[Joe 1320]

if you want a high hp reading, you might have to go to a few different dynos until one says what you want to hear.

bwahaha..... thanks, I just blew a mouthful of soda out my nose. That's too funny.

seriously, mustang and dynojet will give you completely different figures. The mustang being significantly lower. As Kevin pointed out, they are best used for before and after readings on the same dyno.

[TimeLord]

I kind of discovered Thursday,the Mustang Dyno guys says his is right and the others are all over generous,as I am sure the DynoJet guys say the others are stingy.

I got my air/fuel which was the goal of my visit,just found it funny there is such a big disparity!!

[wolfdogs]

mustang dynos s*ck. the guy that bought my Comp got tissy cause he had it dynoed on one at CompFEst in norwalk.. 275rwhp......

now Timelord...you know what was done to my CompTA.......

[N20LT4Bird]

My car dyno'd at 460 RWHP and 560 ft/lbs on a mustang dyno, when I was expecting much closer to 500 RWHP and 600 ft/lbs. The guy that ran the dyno said that his numbers are consistanly a minimum of 10-15% lower than a dynojet. He referred to the dynojet as "hollywood" horsepower....inferring that the mustang dyno was more accurate....who knows? Its really the before and after that counts though.....and your track numbers.

[Dave Vince]

Dyno's

When my Beretta had the smaller motor in it, (488 BB). It ran 5.60's at 122 mph, in the 1/8th. MPH calculators showed that to be around 700 hp at the flywheel. Had it rear wheel dyno'd and it showed 526 hp at the rear wheels,for a 30% drivetrain loss, which I guess is possible with a very loose converter etc. I never put much reliability in dyno's, except for tuning purposes. My best guide was the mph ran at the track. Take into consideration weather conditions, temp, barometer, and humidity, adjust accordingly, and you have your most accurate dyno. A poor start or traction will have little effect on your mph, so you can judge accordingly. Never dyno'd the big motor but it ran 135 in the 1/8th, which was supposed to be around 1000 at the flywheel.

[Dave Vince]

Dyno's 2

Forgot to give you the calculations for 3700 lbs at 112 mph. The figure is shown to be 400 hp at the flywheel. If you figure a 22% drivetrain loss, which is supposed to be average??? This would indicate 312 hp at the rear wheels. This is all theoretical, but it seems to indicate that one dyno was high, and one was low.

[TimeLord]

mustang dynos s*ck. the guy that bought my Comp got tissy cause he had it dynoed on one at CompFEst in norwalk.. 275rwhp......

now Timelord...you know what was done to my CompTA.......

Yes I do Ken,about EXACTLY what is done to mine!!!

My 12.3 is all the dyno that is really needed,just found the experience interesting!

So Ken,since you never went to the track with yours,mine is a reasonable estimate of what you would have ran.

[wolfdogs]

Yes I do Ken,about EXACTLY what is done to mine!!!

My 12.3 is all the dyno that is really needed,just found the experience interesting!

So Ken,since you never went to the track with yours,mine is a reasonable estimate of what you would have ran.

and the young man that bought, who doesnt have much drag racing experience, ran a 13 summin and got mad........




some guys in the stands said it sounded like he had trouble with 3rd.....

oh well......

tis history now....

[fastTa]

I must have one of the quickest 298 RWHP Z28s in town,I have trouble making any sense from the graphs also[no scanner,sorry].

My car's raceweighs is 3700 LBS and it traps 12.3s at 112?

Very confuzzled!!

A few years ago[before the 1.6 RRs] I dynoed 352 RWHP on the DynoJet and ran 12.9s.

In your 3700lb raceweight trim at a 112 trap speed, you are making roughly 395 RWHP.

Mustang dynos are crap for true RWHP data. But you should stick to the same dyno for establishing accurate gain measurements from future mods.

[Injuneer]

298 only sounds at least 50HP too low .

They mist have done something wrong. About a year ago Hot Rod magazine did a comparison of the same car (an HP-challenged Mustang GT with 210rwHP) on 5 different dynos. The difference between the DynoJet and the Mustang on rwHP was only about 7%, if I recall correctly, yet the difference on rw torque was over 15%.0

.... MPH calculators showed that to be around 700 hp at the flywheel. Had it rear wheel dyno'd and it showed 526 hp at the rear wheels,for a 30% drivetrain loss, which I guess is possible with a very loose converter etc...

526 / 700 = 0.751 = 24.9% loss. Believable with a loose, non-locking convertor in something like a TH400, big slicks, etc. 30% loss would only net you 490rwHP.

[fastTa]

The guy that ran the dyno said that his numbers are consistanly a minimum of 10-15% lower than a dynojet.

That is about right. Superflow's and Dynojets are definitely more accurate and are not "Hollywood" horsepower unless they are doing dyno tricks.

I gotta agree though, the track is where it counts.