North American Turbocoupe Organization



Converting a 87/87 T/C from automatic to 5 speed
anasazi4st Offline
Senior Member
#11
(11-08-2021, 04:27 PM)spittinfire Wrote:
(05-07-2021, 12:54 AM)teal95 Wrote: I've done several but always used a cable setup from a Mustang.  Pretty straightforward.  Computers don't really matter.  I've always just looped the wastegate line to bypass the solenoid, which gives about 17 psi.

So I'm curious about this.  I did this the other day to my car and I'm only getting around 10# of boost which is what I got before since it's an automatic car.  This is the factory gauge and I know they aren't the greatest but going off the gauge this made no change.  I will say that it does seem to spool up faster and it feels like it made a difference but it wasn't huge.  
Is it possible that the wastegate is opening without signal from the solenoid?  Can it be pushed open if the spring/actuator are fatigued?

No. If you go through the FAQs here and other responses, the auto transmission was not considered performance and was limited to 10 lbs of boost. You’ll probably going to need to switch the EEC-IV computer to a T5OD (manual) transmission to have it recognize that new drivetrain.

At least, that’s what I would try.
Another proud dues-paying member.

1987 Turbo Coupe w/T5OD, 8.8 axle, grey smoke; most options. Got it in 1991 with 41K miles: 3 turbos, 2 heater cores, 1 T5OD full rebuild, 5 clutches, 1 head gasket, 2 Teves II ABS units, etc. later....
Reply

spittinfire Offline
Member
#12
(11-10-2021, 11:52 AM)anasazi4st Wrote:
(11-08-2021, 04:27 PM)spittinfire Wrote:
(05-07-2021, 12:54 AM)teal95 Wrote: I've done several but always used a cable setup from a Mustang.  Pretty straightforward.  Computers don't really matter.  I've always just looped the wastegate line to bypass the solenoid, which gives about 17 psi.

So I'm curious about this.  I did this the other day to my car and I'm only getting around 10# of boost which is what I got before since it's an automatic car.  This is the factory gauge and I know they aren't the greatest but going off the gauge this made no change.  I will say that it does seem to spool up faster and it feels like it made a difference but it wasn't huge.  
Is it possible that the wastegate is opening without signal from the solenoid?  Can it be pushed open if the spring/actuator are fatigued?

No. If you go through the FAQs here and other responses, the auto transmission was not considered performance and was limited to 10 lbs of boost. You’ll probably going to need to switch the EEC-IV computer to a T5OD (manual) transmission to have it recognize that new drivetrain.

At least, that’s what I would try.


I understand what you're saying but I've bypassed the boost control solenoid so it shouldn't it increase the boost to up around 17# ?

I haven't actually swatch the 5 speed in yet but it's coming. I'm rebuilding all the parts to be able to put them in soon. I have a 5 speed ECM I'll use but I'll probably leave the solenoid bypassed.
Reply

88Slowbird Offline
Junior Member
#13
(11-10-2021, 11:52 AM)anasazi4st Wrote:
(11-08-2021, 04:27 PM)spittinfire Wrote:
(05-07-2021, 12:54 AM)teal95 Wrote: I've done several but always used a cable setup from a Mustang.  Pretty straightforward.  Computers don't really matter.  I've always just looped the wastegate line to bypass the solenoid, which gives about 17 psi.

So I'm curious about this.  I did this the other day to my car and I'm only getting around 10# of boost which is what I got before since it's an automatic car.  This is the factory gauge and I know they aren't the greatest but going off the gauge this made no change.  I will say that it does seem to spool up faster and it feels like it made a difference but it wasn't huge.  
Is it possible that the wastegate is opening without signal from the solenoid?  Can it be pushed open if the spring/actuator are fatigued?

No. If you go through the FAQs here and other responses, the auto transmission was not considered performance and was limited to 10 lbs of boost. You’ll probably going to need to switch the EEC-IV computer to a T5OD (manual) transmission to have it recognize that new drivetrain.

At least, that’s what I would try.


you can use a auto computer in a 5 speed car just fine with a manual boost controller set to whatever you want
1988 Thunderbird TC: RR Cam (with Esslinger cam gear), Stinger FMIC, Stinger 3" Exhaust, Aeromotive AFPR, .60/.63 SVO Turbo, Pimp V1.4, Spartan2 Wideband
Reply

teal95 Offline
Senior Member
#14
The TC I have now has the same problem. I've worked on it a bit, mainly checking for leaks but haven't improved the situation any. Wastegate is my next target. Unfortunately I have an 84 SVO in the shop first that needs a wiring harness that still has all of the insulation on it.
'83 & '84 GT turbo EEC-Tuner
'85.5 & '86 SVO twEECer
2x '87 & '88 TC QuarterHorse
'93 LX 5.0 notch Moates chips
3x '95 & '96 GT
Reply

spittinfire Offline
Member
#15
I haven't figured it out yet but I did get the 5 speed put in and what a world of difference that made.
Reply

Cleven Offline
Junior Member
#16
If i decide to put big power behind my T/C im switch from 5 speed to c4.
Reply





Users browsing this thread:
1 Guest(s)



Theme © iAndrew 2018 - Software MyBB