Long story short, over at our shop here, every Evo we throw on our dynos with ACD (not including stock ones) has a big problem.

As the upper RPM's hit, and power gets bigger, we get an awefull shaking/vibrating from the front right corner. We called a few other shops around with Dynopacks, and they have the same problem.

Basically it was explained to us that the resistance put on by the dyno, is screwing with the ACD and making the axle slip. They also told us that its a feature of the evo, to let the axle twist rather then let it break?

Has anyone else heard of or experienced this problem, and if so, is there any way to disable the ACD temporarily for the dyno time, and then enable it again once done?

We're going to be contacting Dynopack, but due to time differences they aren't open yet.

Thanks for any input in advance. We have to get this problem solved ASAP, as Evo's are a big part of our business.

-Ryan@Bishop Motorsports.

 

one of the reasons we chose an awd mustang... i was scared of differential issues.

cb

 

um thats pretty scary stuff right there

 

John Card at Dynapack has informed us that this can be caused by a few diffrent things. Most of the time it occurs in cars that have been lowerd. Lowering the car changes the angle of the halfshafts which causes the vibration. There are a few things you can do to fix the problem. 1) lift the car slightly, using a Jack,on the corner that sems to shake to level the halfshaft. 2) run the car in 3rd gear instad of 4th to reduce the amount of stress on the axels. 3).Try diffrent load control settings such as custom,heavy, or light. 4) try running the car in all of the ACD settings to see what setting shakes the least.
We will try all of the above to find the fix. If anyone has experience with this that may help. Please post.

 

i got my car dyno'd on a dynapack and had no problems and yes i have a 2005 acd evo...

 

Are you certain there were no problems?

 

I like dynojet dynos. Strap it on and go.

 

this isnt a thread on what you like. please post on topic.

 

Month old thread but... I was tuned on a Dynapack dyno by Shiv a while back at Axiom in Tacoma, WA. It was before I put Swifts on though so I think the car was stock ride height. I don't remember any sounds or vibrations its just weird when you let off the throttle and the hubs come to a stop ASAP! None of the EVOs expierenced anything like that, that I can recall.

 

Heres a thread showing the Dynapack 4000 that worked for me..

https://www.evolutionm.net/forums/sh...light=dynapack

 

my buddi and his "2.5 RS" and center diff didnt get along with dynopack dynos either...i guess it has something to do with being a hub dyno...

 

Just lift the ebrake barely up and your awd car becomes a front wheel drive thats what we do on our dyno. Put your car on a lift at do it watch the rear wheels stop spining. The piston in the acd disengage the rear which should help the diffs
Mkae sure your brakes all stop the wheels at the same time also( brakes on the dyno)

 

... have you tried this. Go try a FWD burnout then. It doesn't become a FWD...

 

I read your post wrong we do this when we get done with our pulls to slow the dyno down and not mess the diffs up. Ive used a dyno pack and havent had this issue yet with the upper rpms

 

Im getting tired of you following my post around and talking trash. I posted about my 900whp and you went in and started bashing. Moderators deleted most your stuff.