Problem with Trans after Supercharging Sc400

[iaksa]

Hi everybody,:saeek:
I am new on this forum, and I have one question.
I install recently Eaton M90 on my SC400 '93 and I notice that my car hesitate between 1500 and 2000 rmp. On the same rpm (when hesitate) range car-trans looks like shift to neutral and after 2000 rpm connect to current gear making noice in trans similar when you on high rmp shift from Park to Drive. The question is: Is there any air/vacum line that connecting engine with trans or just that hesitation make problem in the trans. What I know also is thet M90 is not properly sealed to manifold , so all air not going try MFS. That probably cause engine to hesitate but I can not understand connection with trans.
FYI: Kit working on 5psi with after market regulator.

Please Help me.

 

[Lextreme II]

What type of injectors are you using?
What is your fuel control?
Have this problem happen before?

 

[Zuffen]

It could be the converter is not transmitting the full power as it is now operating outside its design parameters.

Be aware the more torque your engine puts out the higher will be the stall speed on the standard converter.

Most people are not aware the a converter with (say) a 1,500 stall rpm with 200lbft of torque will become a 2,000rpm stall with (say) 300lbft of torque.

When supercharging it is a bad idea to go for a higher stall speed because the standard unit will stall at a higher speed due to the increased torque.

 

[iaksa]

- I am using stndard injectors (OEM).
- A company who make a kit (Fat - Australia) recommended to use existing fuel regulators plus "super FMU" (adjustable FMU) to work when car is in the boost. For some reason my installer decided to use aftermarket Regulator (Aeromotive Compact EFI Regulator, P/N 13105), removing OEM.
- I never (before installation) have any problem with my tras or fuel control.

I think that my tras working fine, just engine is not tuned ok.
Because I do not have enought experience, I can just think that trans may be controled by engine thry ECU or thry some vacum line.
This is explanation what mean "hesitate" :
- drive a car until car reach working temperature
- park a car on the driveway, put shifter in Park position
- press on gas just a little bit, engine rpm going up , reach 2000 rpm and then drop to 1500, and if I hold gas on same position , rpm going up to 2000 and drop to 1500 and repeat that again and again
- if I press gas harder there is no droping in rpm

FYI: My car was in exelent condition before installation

Any help will be welcome. Thanks

 

[Lextreme II]

Do u have any pictures of your setup? Perhaps we can help if we can see some of your installations. One possible problem might be your car might be running lean. Aeromotive AFR are 1:1 ratio and most FMU are 1:12 ratio.

 

[iaksa]

I have pictures (attached). I installed led air/fuel ratio meter on main oxygen sensors, and what I can see is that just under boost my air/fuel ratio is between rich and optimal. When I am in the trafic or just normal driving (1000-2500 rpm) left and rihgt side of instrument just bouncing between rich and lean (left side is bouncing more then right). I spoke also with one good Ford installer (Crazy Horse Racing) and he told me that setup will work, and I do not need Vortech Super FMU (I already bought) - it is for 500hp + and it is too hard to tune, only what I need to fix is air leaking between manifold and M90.

Thanks

 

[Nick M]

You might just be overpowering it and it is slipping. Might. I cant say for certain if you have an Austrailian model, but there isnt a vaccum signal to the transmission otherwise.

 

[iaksa]

Thanks,
I hope my car will be today fix (air leak) I will see if car still hesitate on some rpm. If air leak is no more problem than car definently running lean on some rpms (1500 - 2000).

Thanks Ivan

 

[turbo355]

I'm in the preocess of fitting a M90 to my LS400. How did you mount the Idle speed control valve and egr pipes. Also what power did you end up making?

 

[iaksa]

Sorry for late reply,
First of all I do not have too much experience about engine/supercharging so I can not help you with some details. What I know is that my erg pipe is closed, not used. I also notice that my idle is not perfect like used to be, but it is OK, can be problem just on start and when is very cold/winter. My car has 169hp (199lb) before, and after fitting has 210hp (230lb) with some problem what I described before. Right after installation I find out that I need to rebuid my M90, and I have problem with air leak - not seal properly. Problem with hunting (1500 - 2000 rpm) was fixed fixing air leak and adjusting trotile position sensor.
Finally, my car working very good, no hunting no problem with transmition. After rebuilding M90 I am running on 6psi. I did not check my car on dyno after final fix, I do not realy care as long as my car working like I expect.