Ive been try to get some info for the EVO 7 Evo 8 owners on the ACD and Ayc Pump Removal

The evo 7 and evo 8 jdm have the ACD option for the front Transfer and also have the AYC option for the Rear Diff

I know that if you have an acd transfer on your evo , you can remove the transfer and replace it to a non acd transfer version if u want , normally this is done for several reasons that i wont jump into

Here is were it gets tricky :

If you swap to a non acd transfer , u can remove all the ACD stuff like the lines that go to the transfer .. but i want to know if the pump from the ACD can be removed also ?

Reason i ask is because i think the AYC is hooked on to the same pump and reservoir the ACD is connected to

 

https://www.evolutionm.net/forums/sa...iff-w-ayc.html
here is a Pic i found on the pump and bottle

 

Mitsubishi uses 3 different Pump models for the Evo 7-9 series.

First one is the full ACD and AYC Pump.
It sits in the rear of the car, drivers side. ( where the USDM has the Evap box )
It has 3 Lines, 1 running to the front and 2 running to the rear AYC diff.
If you change the ACD Transfer to an non hydraulic one, simply Plug the connection "C" for center at the pump, and remove the Line running to the front.
But leave the Pump, because it needed for the AYC.

Second one ist the JDM / EDM style RS Pump.
Looks the same as the first one, sits in the same place ( where the USDM has the Evap box )
This one has only one line,going to the front ACD. The other 2 Holes are there, but not drilled through ( also the Solenoids are not mounted / drilled )
This one can be removed if the ACD is removed.

Third one is the singe Pump, used for the USDM cars with ACD.
Sitting in the front Drivers side behind Facia.
Can be removed when ACD is removed.

 

Thanks for the info , i appreciate it

the issue here is the Pump is not working at all and there is no intention in repalcing the pump at all , this jdm evo has the pump in the rear and has an ayc diff , so the plan is to remove the transfer with acd , and use a Non ACD transfer and at the same time we wanted to remove the pump from the car ....

But im wondering if By removing the pump (wich hasnt been working for a long time ) what do we do with the Lines that were taken the fluid to the AYC diff ?

WHat harm can this do to the diff ?

How will this affect or benefit for drag racing ?

 

Ok, So the car HAS an AYC Rear Diff.

For Drag Racing, i can tell you by my own experiance that the AYC Rear Diff in working conditions ( also Pump working ) will break easy and doesnt work long.

My Evo 7 AYC rear Diff lasted 35 Launches @ 400WHP, then it broke in pieces ( open Diff, spider Gears broke )
I changed it to an Evo 8 S-AYC, was fine for 10 launches, then the Planetary Gears were done.
An Evo 9 S-AYC hold only 5 Launches, then the same fault.
See the attachments for the final "Result"
I am now running an Stock RS LSD (USDM) rearend for drag, and an Evo7 AYC for round track. ( swapping anytime to meet the requirements i have )

If you want to remove the Pump, then the only solution is to remove the AYC Rear end also and go the RS LSD Route with the conventional LSD Diff. ( like all USDM 8/9 ).
The reason is that the Rear AYC will not work at all without the Pumps, so actually you will end with an Open Diff in the rear.

For an change of the Diff you need:
Diff including Front carrier Bars and brackets
Both driveshafts L+R
Maybe the rear section of the Propellershaft, because the Evo 7 AYC shaft is 1/4 inch longer that the non AYC shaft, and doesnt fit to an Evo 8 /9 USDM LSD Diff

An other Option will be an Carbonetics or Cusco conversion LSD Kit for the AYC rear-end.
They will eliminate the Hydraulic section of the Diff, making them an LSD.
I am not satisfied with this parts, because you are still running the Heavy AYC case around, which is way weaker then the RS Case.

The AYC is not for straight line. Its supposed for coming faster around the corners.
Then it will last really long and is working perfect ( Round track racing )
Here in Europe, almost any Rally Car for Group N and H running the LSD Rear-ends, because its stronger and lighter. On slippery grounds the AYC could not be so effective as on dry surfaces

By the way, if you remove the Pump at all, i am search for these pump units.
If you want to sell it, shoot mean PN. Maybe i can do an offer.
Since all Europe Evos have them, and they sometimes fail, it would be niche to have spares. I am overhauling these Units here in Germany.

Steffen

 

Good info!

 

Thanks for the info

the evo has the rear ayc diff , and the pump hasnt been working for a long time ...thats why the pump was going to be removed from the car .

 

Where is a good place to get a good deal on the hydraulic pump for the rear diff for the evo 9? And does anyone know what the price range is going to be? Pump is failing and I need to get it replaced ASAP

 

Bump can you run with no acd pump at all like deleting the pump and calling off acd plug on tcase if it is solely a drag car

 

bump anyone have a answer this could help lots of people out.