Dock

So the MAHA will not give a reading of all-wheel (or rear wheel if it's not an AWD dyno) horsepower *and* flywheel horsepower? It only presents the flywheel power?

There has to be an algorithm in the computer that compares wheel power to the resistance during spin-down or it wouldn't be able to compute flywheel power.

Dock

Then that makes it pretty expensive...the GIAC Stage 2 software is around $2200.

MarcMF

The MAHA will measure wheel hp and measure transaxle/tire loss
For example :
Measured wheel hp at 6000 rpm = 400 hp
Measured wheel hp at 3000 rpm = 150 hp

The moment that you'll hit the required top rpm ( say 7000 rpm) on the dyno you'll get out of gear and let the car decelerate in neutral to almost idle rpm . The dyno will measure this resistance .

Measured transaxle loss at 6000 rpm = 75 hp
Measured transaxle loss at 3000 rpm = 30 hp

Flywheel hp = wheel hp + transaxle/tire loss ( hp )
Flywheel hp at 6000 rpm = 475 hp
Flywheel hp at 3000 rpm = 180 hp

Dock

Well then it's easy to see that the correction in this case was 18.75%.

BTW, is the MAHA an AWD dyno?

MarcMF

There is a 2WD and a AWD version.
The Bosch and MAHA dynos are the ones that measure transaxle losses instead of using a fixed correction factor.

http://www.maha.de

Dock

I understand it's not a fixed correction factor. And I understand that a rolling start between two cars is more informative than dyno numbers (not likely that very many head-to-head runs will be documented BTW) . But with all the power numbers being floated, they have to be couched in terms of the brand and type of dyno (AWD versus RWD), and the correction factor used, even if the correction factor is a spin down resistance correction factor, specific to a particular engine.

I'm interested in knowing how the MAHA computes spin down resistance when all four wheels are being measured on an AWD dyno.

969DG

MarcMF, where did you get this inflated pricing from? There are only two PSI dealers in the US (Orton Performance and 969 Motorsports) and I know that neither one charges $4000.00.

MarcMF

The $ 3995.00 was quoted by Orton Performance on 6speedonline this summer.

MarcMF

I'm interested in knowing how the MAHA computes spin down resistance when all four wheels are being measured on an AWD dyno.[/QUOTE]

Must be the same type of measurement as on an acceleration run but then reversed.

John D II

FYI - FVD is offering the 996tt DME and software upgrade on sale this month (until Oct.30) for $2,150.00...no affiliation just a heads up for anyone interested.

Woodster

Software and BMC air filter is $3200 from Orton
(I do not know what 969 price is).
I put on about 600 miles this weekend in Central Wisconsin after my
new plugs were installed and I am completely satisfied with the PSI
software. Loads of torque (pulls like a big V-8) and no CEL's, no misses.
Runs perfect! Just letting you guys know there are alternatives to GIAC,
and I think the numbers that PSI, FVD and Cargraphic post are more realistic
than Upsolute and GIAC. C'mon almost 100 Horsepower from a "chip"????
Would be best to do some fun runs side by side...
Cheers.
MK

PorschePhD

Marty,
None of the GIAC dealers that I know will quote 100HP from a chip. That is a bit inflated. I know we sure as heck don't. We have proven on the dyno what the numbers are and have posted them. Few still have yet to post real dynos. I think for 1995.00 I would be willing to put our chip up against anything. Lets do some 60-130 measurements and see where the cards lay. But please keep in mind we do not say it is worth 100 for just a chip.

Dock

I remember lots of discussion about Upsolute versus GIAC over on 6speed (a few years ago). The dyno charts and real world head-to-head rolling start pulls showed that Upsolute was delivering the advertised goods.

Kevin

Mark, on the Maha after you hit your peak RPM you bump your gear shift into neutral, the Dyno will measure the drag against the eddy current motors.. This resistance is calibrated into a HP factor. On the Maha dyno sheet the lower line on the graph is a plot of the resistance.

Woodster

Johnny G:
yes car pulls to 1.0 bar very quickly now, and I have seen 1.1 register just briefly.
Does not miss a beat now--perfect drivability!
MK