How to convert a Mk2 Turbo Gearbox (E153) to FWD

[Paul Woods]

As part of dara's 3s-gte corolla conversion we had to use a Mk2 turbo gearbox but convert it to a Front wheel drive application for use in the Corolla, so i thought i would do a mini write up about it.This mod is not very well documented on the internet, i only found a few vague pics and not very well described either.

So we did it ourselves and this shows how you too can convert your E153 to FWD for use in a celica or corolla.

The subject gearbox is a rev3 turbo one, we also used all of the conversion parts from a broken Gt4 gearbox.

First step is to remove the Mr2 linkages, make sure the gearbox is in neutral, this is important or you won't be able to remove the selector shaft....



Next remove the selector detent on top of the gearbox and the four bolts holding the end case of the selctor housing and remove the housing itself....





Slide the selector shaft out....



Take your Gt4 selector shaft/housing and forks (all one unit that is removed from the Gt4 box in exactly the same way) and slide it into the Mr2 selector housing.... Toyota in their wisdom used the same internal components selector wise on the mr2 turbo and Gt4 gearboxes....



Next we need to block off the old Mr2 selector shaft hole that is still on the other side of the housing.It has a removable oil seal in a steel casing on that end, tap this out gently...



Here you see it removed, now there are several ways to block this off ranging from making a plug that fits the seal exactly or simply filling the seal with something else, it doesn't matter as long as it won't allow oil to splash out.We chose to insert a metal disc over the seal and bonded it in.



Here it is sealed...



Refit the seal housing and that is it oil tight....



Now the Gt4 has pre-drilled and tapped holes for the selector bracket...



On the Mr2 casing the raised platforms are there, but no holes present.... bummer!



So you need to accurately centre pop these, drill them and tap them out to take an M10 x 1.25 bolt.On the left hole do not drill any deeper than 15mm or you will drill into the gearbox itself, now there is no harm in drilling right through, the Gt4 box is drilled that way, but you will end up with aluminium swarf going into the box..... not good.

Once you have drilled and tapped those holes you can also mount the Gt4 cable holding bracket, these holes ARE present on the Mr2 box...



Finally fit the gt4 selector arm and that is it! One Mr2 turbo gearbox that now belongs in a FWD car....



Hope some of you find this useful.

[Big_g]

Absolutly amazing write up mate. Been looking for this kinda info for a wee while, i knew about swapping the selector stuff over but didnt know exactly what needed tapped (no one gave any details on that part,lol) Looks easier than i thought (famous last words)

[Paul Woods]

It really is that simple, when i was researching it some people made it sound like handling raw plutonium :)

[Big_g]

Now all you need to do is a write up on the wiring side of the conversion rotflmao

[stevehall]

Nice work Paul, I've wondered how this is actually done. Lots of hearsay floating around, but it's good to see a proper walk through on the topic.
Did your scrap GT4 box come with the transfer case? You made me think about the 1MZ clearance again.

[OlberJ]

Does the Mr2 turbo end plate fit on the GT4 box once you've removed all the GT4 bits?

Where the yellow line is?

[AlunJ]

That's a fantastic writeup there, who would have thought that'd be so easy to do?
Now you've got me thinking about how difficult it really is to convert a FWD box to RWD.

[knightrous]

Now you've got me thinking about how difficult it really is to convert a FWD box to RWD.

I'm interested too, getting hard to find an MR2 S54 gearbox over here, but I notice it's a bit easier to get a Celica S54. Might save me some time and money if I can just convert the shifter over.

[Driftin_AW]

As part of dara's 3s-gte corolla conversion we had to use a Mk2 turbo gearbox but convert it to a Front wheel drive application for use in the Corolla, so i thought i would do a mini write up about it.This mod is not very well documented on the internet, i only found a few vague pics and not very well described either.

http://fasterthanjesus.net/technical/mr2box.html ;)

[Paul Woods]

Nice one malcolm, i could have done with that guide!

Steve the transfer case is here so i will be seeing what 2gr clearance is like, but looking at it i'd be amazed if it worked.

Olie the Mr2 diff cover plate will bolt onto the Gt4 box once you have removed the transfer box, but the reason you can't simply do that to a Gt4 box and use that is because it does not have the same diff as an Mr2, there is actually a shaft assembly coming out of the Gt4 box on the transfer box side.

So to properly convert a Gt4 box to FWD you would need to open it up, remove the diff and replace it with an Mr2 one.... too much work versus just doing the linkage mod to an Mr2 box.

Converting a RWD box to FWD is the exact opposite of this write up except you need to drill a hole in the front of the FWD box where the Mr2 selector needs to come out (where i have blanked off the Mr2 shaft oil seal hole in this guide) and install the oil seal.... that is a much trickier job though and slightly inevitable that "some" swarf is going to enter the box in doing that.