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I've been collecting parts over the last several months to upgrade an original Ultima. I really wanted a tranny with a slipper on it and I picked up a used Pro-X tranny. For some reason I thought I would be able to drop it right in with no mods. Turns out the Pro-X tranny is a little shorter. Heres a pic..



I'm only planning on running a very mild brushless motor in it. I'm thinking of just using some plastic spacers underneith, but I'm wondering if you guys think the torque of the motor might bend those plastic spacers? I'm just worried about stripping the gears inside. Thanks in advance!

Hmm. I thought those trannies were drop ins as well. How far off the chassis is the tranny? In the pic the gap looks pretty big - 3/8"? If you are worried about the case flexing and trashin gears, just make yourself a spacer out of some plate stock. I think it would be fine... BTW did you pick that up as a BIN a week or two ago? I was watching that one too.

Yeah, I thought those were drop in too. There's a thread here someplace about someone installing this tranny into an Ultima.

Here's one: http://www.rc10talk.com/viewtopic.php?f=30&t=18616

RichieRich wrote:Yeah, I thought those were drop in too. There's a thread here someplace about someone installing this tranny into an Ultima.

Here's one: http://www.rc10talk.com/viewtopic.php?f=30&t=18616

looks like an plastic spacer between the chassi and tranny.

mvh isobarik

you could split the top part of the rear bulkhead, remove a section and drop it lower so the upper mount point that connectsto the tranny 'd be right in place.

Only question is: will your outdrives end up at a suitable height?

Yeah its pretty close to 3/8". Heres another pic of them side by side.



I'm kinda thinking about talking the gears out of the original tranny and shaving the bottom 3/8" off the case and using that to fill the gap. The holes would match up and the outdrives would still be at the same height as the original tranny so that shouldnt be a problem.

Yes, losiXXXman, I picked this up BIN a few weeks ago. I kicked the idea of buying it for about a week, and when no one else bought it, I figured I'd pull the trigger.

I wonder if the taller tranny case is the reason why the A&L website says the leathal weapon transmission is only for graphite or aftermarket chassis...because it sits lower.
http://www.vintageteamaandl.com/

I think it's mainly because the A&L trans does not work with the tube frame's typical body and rollcage.
I believe there's a note about what to when you use it in a triumph or on a pro xl: the lower outdrives of the A|L interfere with these cars arms unless you raise it if I remember correctly.

I've been gathering parts for my ultima build and I was going to use an SST trans. There is a spacer that allows you to use it for the ultima.

I don't really get why you want to use this specific tranny guys: I've not heard much good of it and putting such a big spacer is gonna raise the motor a lot

highwayracer wrote:I've been gathering parts for my ultima build and I was going to use an SST trans. There is a spacer that allows you to use it for the ultima.

What is this spacer you speak of?

Mr. ED wrote:I don't really get why you want to use this specific tranny guys: I've not heard much good of it and putting such a big spacer is gonna raise the motor a lot

I agree Mr. Ed, I havent heard the best things about this tranny either. I really wanted to copy your stealth idea, but I thought I would take the easy way out and try something that just dropped in. One thing about using a spacer under the SST though, it will only raise the motor up about as high as it would have originally been with the standard Ultima tranny. I suppose if the SST doesnt work I'll force myself to to a stealth setup.

BTW, I use the A&L transmission on my Ultima build. The A&L requires some drilling with the included template and is almost a drop in mod. I actually ran across an SST transmission at a hobby shop but just left it. I remember people talking of melting the gears. It's really cool, though.

If you can find a Triumph trans, it's an easy mod...mine's been nearly bullet proof for years.

The bolt pattern is exactly the same as the Ultima's. The only change needed is a simple spacer plate.

The belt trans is smooth as butter...I run mine with a single belt vs. the dual...never a problem.

Mr. ED wrote:I don't really get why you want to use this specific tranny guys: I've not heard much good of it and putting such a big spacer is gonna raise the motor a lot

Mr.Ed is right, this tranny is garbage I have the same one on my xrt pro. It keeps slipping when i use with a 17-turn brushed motor. Only seems to work well with lower powered motors.

Diggley wrote:If you can find a Triumph trans, it's an easy mod...mine's been nearly bullet proof for years.

The bolt pattern is exactly the same as the Ultima's. The only change needed is a simple spacer plate.

The belt trans is smooth as butter...I run mine with a single belt vs. the dual...never a problem.

It's an easy mod but I guess you'd have to do a bit of a hack job if you want to use the first generation body and cage.
But that's true for almost anything you can do... except for the trackmaster tranny perhaps.

I have 3 trackmaster belt trannies, but still need to check if it's possible to put an a&l slipper on them. Might not be worth the hassle though as the balldiffs are gritty and slip easier than a slipper would when they are set for smooth diff action.

I'd like try a bullet racing tranny, but they're not around so much

Next week I'll make some pics of my friends ultima with the B4 rear end