AWD Dyno - What do I need?

[MileHighV]

Okay - Looking to do a baseline dyno pull (Denver metro), before I install upgrades.

I had an appointment scheduled with a local place, but they called today (4 hours before my apt!), to tell me that they can not do the pull, as there is a problem.
The AWD dyno's rollers are different sizes, and unlinked, so they are telling me that the transfer case ECU will freak out, and not let me continue to apply power - they say they tried with a different SHO a month ago, and no go.
They have a DYNOJET 248/224 Inground All-Wheel Drive, Rolling Chassis Dynamometer.

So - Trying to educate myself - What do I need to ask for from a Dyno shop?  Anyone else have dyno issues?
Anyone local to Denver had dyno pulls done on a SHO/MKS?  If so, please let me know where.

Thanks everyone!

 

[ajpturbo]

I've been told u need mechanically linked rollers that way u are not relying on the awd system to turn the rear rollers....I think because it's hard on the clutch packs in the rear diff and they can only transfer so much torque and the drum is heavy

 

[SHOdded]

Yup, need an AWD dyno whose rollers can be linked for our platform's purposes.

 

[Livernois Motorsports]

You definitely need to ensure the dyno has linked rollers.  I cannot think of anything other than this that you would need to ask the shop other than this.  I will ask around here with the guys in wholesale to see if they know of any shops in your area that could be of assistance as well. 

 

[4DRHTRD]

I would suggest linked but all the dynos on my car were unlinked. The key was to make sure to lightly powerbrake on take off to make sure the car engaged the PTU.

 

[BiGMaC]

The DynoJet you list at the shop you are using should work fine.

 

[Livernois Motorsports]

The problem with an unlinked setup with an active differential is the car will be trying to vary the power output from front to back during the pull, which can not only cause premature wear, but drastically skews the power number since you will have a varied rate of acceleration on the drums. Older fixed AWD systems (like the old GMC typhoons) could use the free-spinning awd dyno because it was a mechanical unit. But with the haldex, and haldex type systems it does have negative consequences by running it unlinked.

 

[MileHighV]

Sorry for the late reply:

I finally gave up on a pre-mod dyno run - the only linked dyno in the area was not interested in my business (never called me back after multiple messages).
I guess that two dyno runs (3 pulls each) was not enough $$ for a platform that he has never run before (seems to be an EVO shop).

I am enjoying the increased power, even though I do not have an exact number of the increase.
Definitely more power throughout the range, deeper/less raspy exhaust - I love it!!

 

[Livernois Motorsports]

Sorry for the late reply:

I finally gave up on a pre-mod dyno run - the only linked dyno in the area was not interested in my business (never called me back after multiple messages).
I guess that two dyno runs (3 pulls each) was not enough $$ for a platform that he has never run before (seems to be an EVO shop).

I am enjoying the increased power, even though I do not have an exact number of the increase.
Definitely more power throughout the range, deeper/less raspy exhaust - I love it!!

Glad to hear you enjoy the tune and mods!  I have found even working here with 2 chassis dynos that having something in writing showing you the performance is not such a big deal to most once they drive the vehicle.  To myself personally, I prefer to experience the additional power and drivability, to feel the difference before and after, rather than look at a line graph with someone telling me how great it is. 

Don't get me wrong, dyno sheets are a necessity in this industry to show potential customers how much power it could make.  But I have found most guys are more excited to get behind the wheel and cruise after their car is done rather than discuss their dyno numbers. 

Let us know if there is anything else we can help you with and hope you enjoy the ride!

 

[PokerMunkee]

Let's go to a drag strip! 

I think Pueblo is still open.