5sp swap.

kw90supercoupe

Registered User
I have a 90 auto and im getting board with the auto. I have all the good motor internals sitting at home till winter when i pull the motor and rebuild it. So while im at it i want to put the 5sp in her. I think i just need the trans drive shaft pedal master cylinder and maybe the comouter or ecu from a 5sp car? Please give imput if u have done the swap or know anything about it.
 
I have a 90 auto and im getting board with the auto. I have all the good motor internals sitting at home till winter when i pull the motor and rebuild it. So while im at it i want to put the 5sp in her. I think i just need the trans drive shaft pedal master cylinder and maybe the comouter or ecu from a 5sp car? Please give imput if u have done the swap or know anything about it.

I have never done the 5 speed conversion but know how it's done, parts needed off the top of my head are:
5 speed trans
Clutch and brake pedal , from what I have heard it's possible to modify the existing brake pedal to work.
Flywheel, clutch with pressure plate, pilot bearing, etc. The slave cylinder in the trans should be replaced as a safeguard.
Clutch safety switch with pigtail to wire it in.
Driveshaft.
ECU.
Trans cross member
Hydraulic line from clutch master to slave
Clutch master and reservoir .
I am sure I missed a thing or 2 but the experts will chime in for sure.

It's a lot of work for sure. Maybe you should consider a upgraded auto instead ?? My 92 has a Lentech street terminator plus in it and let me tell you there is no human hand that could shift that fast.
Just a thought.
 
Things absolutely needed for the swap are
-M5R2 Trans
-SC flywheel
-SC clutch
-SC slave cylinder
-Pilot bearing
-Clutch hydraulic line
-Clutch slave cylinder
-Clutch master cylinder and reservoir
-Clutch Pedal
-Driveshaft
-Shifter
-5-speed console top

Other things that it would be nice to have are
-Engine separator plate. The auto one will work, but won't cover the whole area where the flywheel is.
-5-speed shifter plate (bolts to the floor where the shifter comes through to seal it up
-B&M Ripper shifter (makes a huge difference in the way the trans shifts)
-New slave cylinder (don't want it to go bad and have to drop the trans out to replace it
-Trans crossmember (one from an auto can be made to work, but if you can get the manual one, it will be one less thing to do_
-Aluminum driveshaft (stock 2-piece is no good for high performance, so it is a good idea to upgrade)
-Clutch interlock wiring, if you want to wire it into your starter or cruise control. Personally, I just leave that out.
-Brake pedal from a 5-speed car. The alternative is just to cut down the pedal portion of your stock pedal and install a new pad.
-Gears. M5R2s work better with shallower gears in the rear. If you have the stock 3.27s, that might be OK, or you might want to swap to 3.08s or 2.73s. If you have changed to 3.55s or higher with your auto, you will definitely want to get something closer to the stock ratio in there.

The ECU is not needed for a swap in an 89-93 car, since that trans isn't controlled by the computer. There will be some calibration differences, but that could all be changed in a tune if you want, so there isn't any particular need for the manual trans ECU. The car will run and drive just fine with the auto ECU without a tune or anything. If swapping into a 94/95, you will need either a tune or the manual trans ECU.

The clutch line can be hard to find in good condition. It is possible to make a new one using adapter fittings and AN lines, but that would put the trans side connection inside the bell housings, so if you need to drop the trans, you will need to disconnect it from the master cylinder, and then re-bleed the system, as opposed to the quick disconnect factory fitting, which prevents air from getting in when it is disconnected.

One other comment on this swap; pull the dashboard out of the car to do it. There are many write-ups that say to cheat and use a right-angle drill to drill the holes, and then cut a tab off the pedal to bolt it in. Pulling the dash isn't that hard, should take maybe 2 hours tops to get it out of the way, and another 2 going back in, and that is if you have never done it before. Modifying the pedal to not have that tab that bolts to the cowl panel is just asking for a cracked firewall, and by the time you mess around with leaning under there trying to get enough room to drill the holes, you'll probably only save about a half-hour of time, so don't even waste any time trying to figure out a way to not pull the dash. Just pull it out, drill your holes, and mount your pedal. It may take slightly longer, but you will be able to see what you are doing and where you are drilling, and you won't be laying on your back getting metal shavings in your face the whole time.
 
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Ok so i should be getting everything from a 5sp sc so if he gives me the trans drive shaft, master cylinder hydroclic lines and pedal, trans bracket and shifter plate. All of thoes would be from a 5sp sc. Now the fly wheel from my auto will work? I plan on getting new clutck kit when i get with throw out bearings and all that good stuff. Also i do like cruise control when i go on trips how easy is that to hook up. Please clarify if i say anything wrong.
 
Don't do it.

What these guys are telling you isn't wrong, but the wiring to make the clutch interlock, cruise control, and EEC programming work correctly is complicated. The 90 SC dash wiring harness is not the same between the auto and 5spd, and the changes necessary to make everything work correctly is more difficult than you think. I know, I've done this swap several times. On a 91-93 it's a pretty simple swap, but on the 89-90 it's no fun.

Unless of course you don't care about those electrical things working properly. Mechanically it's not that hard to do.
 
I am good with wiring is this something that can be explaned on here? Or should i give u a call. U can still tune it when i put put that blower and other things on it right. I it only affects the cruise control right. bought the fordged pistions rods and complet moter kit from u.
 
The cruise control will still work after the swap. What won't work without some rewiring is the feature where the cruise will shut off when you press the clutch in. As long as you know this, and either hit the brake or turn the cruise off before pressing the clutch, you will be fine. If you want that feature to work too, the easiest way short of swapping the whole dash would be to wire the clutch switch to the brake switch signal going to the cruise control module, and put a diode in the brake side so it doesn't trigger the brake lights every time you clutch in.
 
i was reading this thread and saw that the crossmembers were different ,how are they different?iv got a 95 and they look the same to me.show me please.its important because my car is in the shop and i gave them a crossmember from an auto with new bushings to use,on my 5 sp
 
The only differences are the trans mount, and there is one hole that is used to clip a connector in place that is not there on the auto crossmembers. At least that is on the 89-93 ones. The 94/95 ones may be the same, I never really looked.
 
You will have to wire the starter circuit through the clutch switch. That part is easy.

The cruise feature is operated through the EEC because the cruise is actually part of the EEC. Part of this control circuit is also in a loop through the transmission neutral switch and the clutch switch so that the EEC knows whether or not the trans is in neutral or if the clutch has been depressed. If you don't wire it right then the EEC won't know if you are in gear or not and will tend to stall when you depress the clutch. Because these circuits are looped inside the dash harness on the auto cars, you can't just tap in wires here or there and make it work. You have to find the circuit inside the main dash wiring harness, cut it in the right spot, and then wire it through the proper switches. A contortionist can do this with the dash in the car. The last 2 times I did this it was with the dash out. I don't think I can explain the process in a post or email. In fact I'd probably have to sit down with a schematic and let out some smoke to re-figure it all out which is not likely going to happen due to the long list of things I must do in the mean time.

I think you might be able to plug and play a 5spd dash so that may be an option. Just make sure it's an 89-90 dash as the wiring harnesses are totally different in later years.



Cross member is essentially the same for all practical purposes. Tranny mount is the same too, but the bracket that attaches it to the transmission is different.

Also be aware, that when swapping pedals, the 5spd brake pedal and bracket from the 89-92 is different from the 93, so if your 5spd donor parts are from a 93 or later it can cause problems with the brake pedal and bracket.

Also not a big deal, but the transmission harness plug is different on different years and will not necessarily plug and play. I which years were which. I think it's an 89-92 vs 93+ thing.
 
"Cross member is essentially the same for all practical purposes. Tranny mount is the same too, but the bracket that attaches it to the transmission is different".{ Dave Dalke }

Robbie I told you there was some difference !! Just could not remember what.
The MAN has spoke. He knows more of whats needed on these cars than anybody on here. PM him with your problem, he will point you spot on.
Angelo.
 
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Auto to Manual Swap

Thanks Guys
it seems the answer is it can be done in a 94
I will keep looking for that 94 for now and see what comes!
 
Well what is diffrent the bracket that hooks up to the exhaust looks exactly the same. Isthe mount that goes between the rubber trans mount and the trans.
 
Oo and fyi if u use the 5sp dash harness and computer their is no issues with start, clutch pedal and cruise control. But dave i have a check engine light due to the egr now. Can that be changed with a tune
 
The swap is not quite as simple on a 94/5, just FWI. Wiring is quite different due to electronically controlled transmission.

Yes, the EGR can be turned off in a chip or you can use a non EGR EEC.
 
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