th4oo swap this weekend
th4oo swap this weekend I'm hoping to do a th400 swap into my 98 formula.. Used to be a M6 this weekend. t56 is already out. I will be getting most everything I need for the swap from LTLHOMER.. Crossmember, driveshaft, convertor, tranny, shifter, shield, and a few misc. thing. I have the flexplate and cooler coming.... I'm just trying to prepare for the "What ifs".. I got a lot of info from this link.. https://ls1tech.com/forums/showthrea...400+conversion ..
I just want to be as prepared as possible.
speed sensor? How to do that?
Clutch sensor to make sure the car only starts when in park?
How to install transbrake?
I'm most worried about the shifter and that area.. flexplate, convertor, tranny, driveshaft.. shouldn't be too hard in that area.
Would most recommend getting an A4 console? Currently have the M6 obviously. Just any heads up would be helpful
I just want to be as prepared as possible.
speed sensor? How to do that?
Clutch sensor to make sure the car only starts when in park?
How to install transbrake?
I'm most worried about the shifter and that area.. flexplate, convertor, tranny, driveshaft.. shouldn't be too hard in that area.
Would most recommend getting an A4 console? Currently have the M6 obviously. Just any heads up would be helpful
Im not sure on the speed sensor, 90's truck???
Park/Neutral safety switch can be wired using the wires originally going to the start disable switch on the clutch. Its the black switch, not the white one. Just run new wires from that location to your park/neutral safety switch on the A3 shifter. Polarity doesnt matter.
The transbrake needs to be wired to a momentary pushbutton switch. Probably wouldnt be a bad idea to wire it up using a relay. PM me if you need help with that.
As far as the shifter, gonna need something to cover the hole in the tunnel, and something rigid to mount the shifter to.
Id use the M6 console, because IMO it comes out looking cleaner. That really depends on the shifter you use though. Do a search on here regarding the exact shifter your planning to use and you'll come up with lots of pics and install tips.
Park/Neutral safety switch can be wired using the wires originally going to the start disable switch on the clutch. Its the black switch, not the white one. Just run new wires from that location to your park/neutral safety switch on the A3 shifter. Polarity doesnt matter.
The transbrake needs to be wired to a momentary pushbutton switch. Probably wouldnt be a bad idea to wire it up using a relay. PM me if you need help with that.
As far as the shifter, gonna need something to cover the hole in the tunnel, and something rigid to mount the shifter to.
Id use the M6 console, because IMO it comes out looking cleaner. That really depends on the shifter you use though. Do a search on here regarding the exact shifter your planning to use and you'll come up with lots of pics and install tips.
FormulaFire, for your Park/Neutral safety switch tap into the purple wire and the dark green wire on your lower clutch switch. As Fire67 said it is the black switch. I had to hang upside down off the drivers seat to get it. Also if you would like your reverse lights to work, you will need to tap into the brown wire and the light green wire on the M6 harness (passenger side) underneath the car. I ran these wires to the switch on my shifter thru a hole in the plate that I mounted my shifter on.
I used a big sheet of scrap metal to mount the shifter on and then on the underneath side of the car I took the old shifter cover (rubber piece that has screws to cover the M6 hole) and put it on the bottom of the car and ran the screws into it to cover the bottom of the hole.
I don't know which shifter you plan on using, but the B&M Hammer shifter is the one I opted for. It's a little tricky to get it in the right spot, but if your patient and persistent you will be able to get it to fit and still be able to use your old M6 console.
When I installed my transbrake switch I ran one wire from the push button switch to the hot wire on the t-brake solenoid. The other wire on the push button switch I ran to a 12 volt power source. (I used the pink wire on the traction control harness). Of course you will have a ground wire coming of the t-brake solenoid, it should be connected to a good chassis ground.
As far as the speed sensor you could go this route...
If you have any other questions let us know. Or feel free to send a PM. 
I used a big sheet of scrap metal to mount the shifter on and then on the underneath side of the car I took the old shifter cover (rubber piece that has screws to cover the M6 hole) and put it on the bottom of the car and ran the screws into it to cover the bottom of the hole.
I don't know which shifter you plan on using, but the B&M Hammer shifter is the one I opted for. It's a little tricky to get it in the right spot, but if your patient and persistent you will be able to get it to fit and still be able to use your old M6 console.
When I installed my transbrake switch I ran one wire from the push button switch to the hot wire on the t-brake solenoid. The other wire on the push button switch I ran to a 12 volt power source. (I used the pink wire on the traction control harness). Of course you will have a ground wire coming of the t-brake solenoid, it should be connected to a good chassis ground.
As far as the speed sensor you could go this route...
Originally Posted by SUX2BU
Posted this a long time ago but since the search doesn't go that far back anymore thought i would repost it.
splice your speed sensor into your front wheel sensor. if were an M6 put in 2.76 for your gear ratio, measure your front tires and put that in as your tire size.
You will lose your ABS.
Ok if you were an A4 you put in 1.175 for your gear ratio. and front tire size for "tire size".
Oh and if you want your speedo accurate please measure the circumferance of your front tire and divide it by pi (3.14) and that is your EXACT tire heigth.
Your welcome.
splice your speed sensor into your front wheel sensor. if were an M6 put in 2.76 for your gear ratio, measure your front tires and put that in as your tire size.
You will lose your ABS.
Ok if you were an A4 you put in 1.175 for your gear ratio. and front tire size for "tire size".
Oh and if you want your speedo accurate please measure the circumferance of your front tire and divide it by pi (3.14) and that is your EXACT tire heigth.
Your welcome.
appeciate it guys.. I'm sure there will be some more questions when it get s closer. Where exaclty is the speed sensor in the front wheel, And how would I input the gear ratio? What size of metal should I get? what type?
speed sensor on back of the spindle. Directly behind the hub in the center. I used SUX2BU 's calculations and they worked out perfectly. On the metal use something workable for forming to the contour of your tranny tunnel but thick enough where the shifter won't move. Mine is a scrap piece from a car fender. I went from m6 to th400 also , you won't regret it.
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Originally Posted by wickedred
I am gonna keep an eye on the progress. I will be swapping my Th400 in real soon.
I used an A4 shifter console, and notched it just enough to get the hurst quarterstick with piston grip thru. The shifter has a button on it, I wired that strait to the transbrake and to a power sourse, no need for a relay. I will be changing this to my purge however, because I have a bad habit of pulling the shifter at launch, so a pushbutton will go on the steering wheel, but that's not important.
You can TRY, to get the speedo workign, but after scewing around wilt all that nonsense forever, we gave up on my car. The sheel sensor didn't work like it "should", and the drive setup that the tranny gets, even when we had it reading right for mph, the odometer was getting mileage put on it like MAD... so we unhooked it all and stopped wasting our time. Eventually I'm gonna lose the entire guage cluster, at that poitn an autometer speedo might find it's way in, but only if it will fit when I fill the new guage cluster when all the stuff that matters.. to me the speedo is the last thing I was worried about. I do drive on the street, I just try to keep it a little slower then the cars around me.
A plate over the M6 opening in the floor is needed, and you will probably have to build it up with some round bar or square tubign to get the shifter to a height that you are comforable with.
You can TRY, to get the speedo workign, but after scewing around wilt all that nonsense forever, we gave up on my car. The sheel sensor didn't work like it "should", and the drive setup that the tranny gets, even when we had it reading right for mph, the odometer was getting mileage put on it like MAD... so we unhooked it all and stopped wasting our time. Eventually I'm gonna lose the entire guage cluster, at that poitn an autometer speedo might find it's way in, but only if it will fit when I fill the new guage cluster when all the stuff that matters.. to me the speedo is the last thing I was worried about. I do drive on the street, I just try to keep it a little slower then the cars around me.
A plate over the M6 opening in the floor is needed, and you will probably have to build it up with some round bar or square tubign to get the shifter to a height that you are comforable with.
I am going from an A4 to a TH400. I bought a TCI Competition TH400 with a T-brake and a Turbo/Action Cheeta Shifter. I just need to find a converter for it now. I am waiting to hear back from Perfomabuilt on the verter. Figured it would be a good idea to step up to a bullet proof tranny setup with the turbo plans.
Originally Posted by wickedred
I am going from an A4 to a TH400. I bought a TCI Competition TH400 with a T-brake and a Turbo/Action Cheeta Shifter. I just need to find a converter for it now. I am waiting to hear back from Perfomabuilt on the verter. Figured it would be a good idea to step up to a bullet proof tranny setup with the turbo plans.
Neil chance are probably the best out there.. I woudn't hesitate to put one of those in my car in a second. I am running a Hughes converter now, and so far it has worked flawlessly, gets my heavy pig moving good, still drives around town fine, etc.etc. Once I get some of the small things ironed out I am expecting to see somewhere in the 10.5 range maybe better on motor, not too bad for a nitrous setup.
Originally Posted by JL ws-6
Neil chance are probably the best out there.. I woudn't hesitate to put one of those in my car in a second. I am running a Hughes converter now, and so far it has worked flawlessly, gets my heavy pig moving good, still drives around town fine, etc.etc. Once I get some of the small things ironed out I am expecting to see somewhere in the 10.5 range maybe better on motor, not too bad for a nitrous setup.
yeah, the hardest part for me was the fabrication of the shifter plate. i just cut a piece of metal out of an old tranny pan and copied the contour and screw hole pattern off of my stock rubber shift boot over to the piece i cut out, then i just screwed it to the tranny tunnel using the stock shift boot holes and screws. its pretty firm and works really good.
everything else was a breeze.
what are you using for a torque arm?
the transbrake consist of 3 parts. you will need a transbrake valve body, transbrake solenoid, and a the transbrake button. Hopefully, you already have the valve body installed in the tranny, if not, your going to need to do that before you do anything. Then you just wire the ground wire from the solenoid to a chassis ground (i used one of the drivers side exhaust heat shield mounting bolts on the bottom of my car), then youll have to run the other wire to your trans brake button, then to 12v source. its pretty easy to do.
good luck with your swap!
everything else was a breeze.
what are you using for a torque arm?
the transbrake consist of 3 parts. you will need a transbrake valve body, transbrake solenoid, and a the transbrake button. Hopefully, you already have the valve body installed in the tranny, if not, your going to need to do that before you do anything. Then you just wire the ground wire from the solenoid to a chassis ground (i used one of the drivers side exhaust heat shield mounting bolts on the bottom of my car), then youll have to run the other wire to your trans brake button, then to 12v source. its pretty easy to do.
good luck with your swap!
I already have a BMR extreme torque arm. SO it's not mounted on the tranny. The tranny also has the transbrake installed. And The guy I bought it from included a plate to mount the shifter on.. He is making it sooo easy for me..
Well I got m 4L60E out of the car and its on the way to be shipped to its new owner. My TCI TH400 is sitting on the shop floor. The Cheeta shifter is waiting to be installed. I ended up going with a BMR TH400 X-member. I ordered a Yank Custom Billet 3000rpm stall converter. It is going to be bad a$$ when the car come up on the turbo. I hope to get it all installed soon.
FormulaFire: How is your install coming?
FormulaFire: How is your install coming?
Originally Posted by wickedred
FormulaFire: How is your install coming?
For a shifter i just used a stock A4 shifter and modified it to work with my RMVB TH400.Shifter locks in 2nd and and then i have to push the button to get to drive and i welded a stop to block out the 4th gear spot on the shifter also fab'd up some brackets for microswitch on the shifter for the reverse lights and a park switch.Car looks as if it was suppose to be a A4 car.Was orginally a M6
BTLFEDSS
BTLFEDSS
I'd like to see what you did btlfed.. sounds like a slick setup! I love the hurst pistolgrip quarterstick I'm using, the shifter is very solid and fits my big gorilla mit perfect.. something most shifter handles are way too small to do. Doesn't look too bad either, I just have to make a little plate to stick on top of the a-4 shift pattern so thw rmvb shift pattern is on there.
I don't have my reverse lights working.. that's the only thing that didn't work (that and the speedo) but I don't see it as a problem.... I don't drive around enough to really worry about getting in trouble for it. Worse case, I'd just put a toggle switch in for the reverse lights.
I don't have my reverse lights working.. that's the only thing that didn't work (that and the speedo) but I don't see it as a problem.... I don't drive around enough to really worry about getting in trouble for it. Worse case, I'd just put a toggle switch in for the reverse lights.