Chosing a manual transmission for my LS engine swap...

orangesicle

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Apr 19, 2012
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Planning out my MK3 Supra swap and I have not yet decided on a manual transmission. Goal is 400-450hp daily driver from a 4.8 or 5.3 vortec engine. Budget for project is about $8k. Disclaimer: this is my first swap. I've spent hours and hours researching this, but I haven't come across a lot of great info.

From what I've gathered, my other options are:

T-56: preferred tranny by LS people. Price is high, though (junkyards say ~$1500 for one with under 100k miles, $1k for 150k+ miles). Another downside is that this would require expanding the trans tunnel. And I am not sure how I would handle the crossmember. Would also need to reposition shifter hole, get a custom driveshaft, and convert the speedo from mechanical to electric (right?), and figure out the clutch hydraulics. Can't find too much information on how bad the tunneling would be, but I'm guessing "not too fun."

TKO 500/600: looks to be $2k+. Hard to justify dropping that much on a transmission for a $500 engine... but maybe that's how it goes? Would also need to do all of the above (I think). Not sure how it would do in the trans tunnel (researching now).

R154: I probably wouldn't be able to find a chassis with this tranny in it (since the turbos are rare). Nonetheless, I'd buy an T154 from a junkyard and swap it in. I've seen a huge variance in reports on what kind of torque it can handle, but 400-500ftlbs depending on how you drive it seems reasonable. I'm guessing I'd break it randomly (could be 10 miles, could be 30k). Another downside is that adapting it to the motor would be difficult and potentially expensive. (But I think this would work: http://www.novak-adapt.com/catalog/kit_gmax15.htm - would I need anything else, though?). Upside is that the trans is less than $300, so even if I blow it up, it won't be too expensive to replace. Provided I don't have to replace the adapter (right?). Other upside includes easier mounting since the car is designed for his transmission. I could presumably keep the driveshaft too.

There are also a bunch of lesser rated manual trans. T5, AR-5, W58 and some others. Most of these aren't rated beyond 250ftlbs or so. These would be nice because they are also ~$300, but I think they would just break. And I'd have the same expenses I'd have with the T-56 (W58 aside).

What am I overlooking or misunderstanding? As mentioned, this is my first build and I still getting a handle on things. Any thoughts or opinions? Additional resources?
 

te72

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Mar 26, 2006
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There have been people who have adapted R154's to LS engines, and T56's to JZ's and 7m's, much of which has been chronicled on this forum alone. Specific threads don't come to my mind, but do some searching and I'm sure you'll find some good info. As for your post, the T56 is a great transmission, if you get one from a Z28/Trans-Am, you won't want to exceed 500-600 ft/lbs unless you're feeling particularly lucky. They're not exactly brittle, but from my time as an SS owner, I looked into boost... seems the stock T56 doesn't like *quite* that much torque.

The TKO variants, I can't speak much of, is that what they used in the Vipers back in the 90's?

Ironically, the R154 is probably your strongest choice out of those. I've seen them take abuse WELL beyond what would normally be expected of the stock output, and they keep on going, save for a couple failures I've seen over the years. They're also quite easily sourced, the turbo Mk3 wasn't quite as rare as you might think. :)
 

destrux

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May 19, 2010
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Speedo in the supra is mechanical FYI... you'd just need to get the proper drive gear ratio for the trans from a speedometer shop, and maybe an adapter of some sort for the cable. If you use one of the non-Aisin transmissions I mean.
 

MightyAl

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Jun 5, 2005
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I am curious where you can find an R154 for $300? I haven't seen a price like that in a long time.

I have put together almost all the pieces to adapt the R154 to an LS engine. I have the novak adapter, chevy bellhousing, advance adapters pilot bushing, wilwood 3/4" master cylinder with an adapter I got from wes beech, quarter master hydraulic throwout bearing, LS flywheel, and LS7 pressure plate. I am still missing the clutch disc but that is because I am not sure where I am going with this set up. Advance adapters has a clutch disc that works for $120, but I have also been talking to a clutch company that can build a full face feramic clutch for $300-$400. There are precious few options out there for a clutch. I would say that I am into this setup for $1400 at this point without the clutch disc. That includes an R154 transmission I bought with the Novak adapter.

There might be more optimal trans choices out there but for me not having to mess with shifter position and buy a new driveshaft are important to me.

Edit:
Forgot about the pass thru adapter for the VSS from JTR.com. That was ~$100 so push the total up to $1500. If you are using the stock ecu I believe that you need it. I have been going back and forth with using either hptuners or Megasquirt3. The pricing is close between the two and I like the tuning features in MS3 but if I stay N/A I think hptuners would be just fine.
 
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