GenIII Hemi w/5-Speed Supra Trans?

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4speeds4me

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I know guys have been putting the Supra trans behind small blocks, but not sure what model. Is the Supra trans strong enough to handle ~500HP? Will it handle full throttle clutch drops? What bellhousing does it require if it's feasible?

Thanks for the help!
 
They use the dakota ax15 bellhousing on the small block. Also Advance adapters makes an AX15-ford bellhousing plate. In theory that could work w/ a QT bellhousing for a ford TKO. If that plate will fit the same on an R154

I believe +/- 500hp was about the limit in the supra(MKIII?) and those supras were surprisingly heavy.
 
magnumdust said:
They use the dakota ax15 bellhousing on the small block. Also Advance adapters makes an AX15-ford bellhousing plate. In theory that could work w/ a QT bellhousing for a ford TKO. If that plate will fit the same on an R154 I believe +/- 500hp was about the limit in the supra(MKIII?) and those supras were surprisingly heavy.
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The manual MKIII's weighed about as much as our A bodies (3000-3400 lbs). The automatic versions weighed (3500-4000 lbs). Anyways, you're about right where the transmissions can only hold about +/- 500hp.

Here's a swap link...
http://board.moparts.org/ubbthreads/showflat.php?Cat=0&Number=3168502&page=0&fpart=all&vc=1
 
Thanks all! I did more digging last night and came to the conclusion that I'm probably not going to go that route. The one thing I've been adamant about is the trans tunnel. I do not want to hack it, so I'll stick with the A833 until such time as I can afford an A855 from Passon, should I decide I really need a 5-speed.
 
A lot of it really depends on what you plan to do with the car. I had every intention of mine being a street legal drag car until I started driving it more. I really didn't feel like hacking up the body for tubs and a cage, so it's become more of fun cruising car with good power. Because of that I was really drawn to an overdrive trans for highway cruising to work and back. If you're just running around town or racing the overdrive likely won't get used much and the extra speed(s) won't be missed. I had an 833 in mine for a few years before I got my T56 setup. Worked just fine and really the car didn't mind cruising at 3000-3500 on the highway (3.55 gears), but I didn't enjoy it as much.
 
Probably going to use 64 A-body 833 gearset in a B-body case, with 2.94 or 3.23:1 gears out back. With my desired tire height I should be turning between 1900 and 2300 rpm @ 60mph, and the deep first gear helps make up a bit of the loss going with a higher rear gearset, while not having the HUGE 1-2 jump that the 833OD has...I might get to a track once or twice a year, but I'll be driving this thing everyday!
 
4speeds4me said:
Thanks all! I did more digging last night and came to the conclusion that I'm probably not going to go that route. The one thing I've been adamant about is the trans tunnel. I do not want to hack it, so I'll stick with the A833 until such time as I can afford an A855 from Passon, should I decide I really need a 5-speed.
Click to expand...

Other than the A855, you can put in a gear vendors. Otherwise you have to hack the tunnel. And if i were gonna go to a modern transimission and insisted on keeping the t-bar suspension, i'd chase down the guy who was selling the T56 crossmembers. You still have to hack the center cross member, but it gets replaced with a great looking piece.
 
You know, magnumdust, I hear what you're saying, and as much as I hate to say it cause I so vehemently disagree with you in other areas ( ;) ) you're probably right. It's the budget that's gonna do a lot of the dictating on this one, and this one little pet peeve I have. If I could tell you beyond a shadow of a doubt that I was going to own this car till I breathed my last, I'd hack away. However, because it is the car that it is, I am trying to keep any "upgrades" required for my "vision" to bolt-on. Should a later owner decide they want to take it back as close to factory original as possible, it would be easily doable.

The "motivation" for this car came after we almost bought an R/T 6-speed Challenger, so I LOVE the idea of the T56...
 
The T56 swap isn't all that hard and I still have my torsion bar setup, but it does require a fairly big hole in the floor. My car had already had a 4 speed installed by a previous owner (somewhat poorly), so after cutting out the hump I was already almost half way there. I figured if I ever wanted to do a vintage trans I'd rather redo the whole tunnel with stock replacement metal anyway.

I made my own crossmember as well. No offense to the one being sold here, but I didn't think it was worth the cost. I made mine for probably under $50, but then again I had access to a plasma table at work and some scrap metal.

My car was also a slant 6 auto out of the factory (I think at least from what I can tell), so it has fairly little value and cutting it up doesn't bother me quite as much. If you have a rare car or even just a desireable one like a 340 or big block I'd understand not messing with it.
 
i had the R154 behind my 340 almost 5 years and swapped 2.5 years ago the engine to a 6.1. So I can say it works. Not the superbest for drag race ( 14.00 @ 170 km/h with a stock and carbed engine- Sorry, I am metric ) but on the autobahn killer ( 250 km/h ). Thanks to the 5th gear.

I re-drilled the flywheel to the new bolt circle. That was it. Peace of cake like you guys are saying :)
 
Buschi340 said:
i had the R154 behind my 340 almost 5 years and swapped 2.5 years ago the engine to a 6.1. So I can say it works. Not the superbest for drag race ( 14.00 @ 170 km/h with a stock and carbed engine- Sorry, I am metric ) but on the autobahn killer ( 250 km/h ). Thanks to the 5th gear.

I re-drilled the flywheel to the new bolt circle. That was it. Peace of cake like you guys are saying :)
Click to expand...

So, by my calculations, you ran a 14-flat at 106mph. Your mile-an-hour is more in line with a high 12/low 13-sec 1/4, which tells me you were scratchin' for traction. What were your 60-fts like?

Are you saying you took a regular 6-bolt flywheel and had it redrilled to the 8-bolt pattern? Did you weld up the old holes? I've been wondering if this was an option. Which starter did you use?
 
see my slip :) 255/65 street tires, 4.10 gears. shift point at 5500 rpm
my next plan is a bit more radical cam shaft, semi slicks ( no slicks in street legal class ) and caltracks. and working on my reaction time .... :)
 

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yes, i welded the 6 existing holes and drilled 8 new. But a new flywheel for you US guys is the better choice... :)
starter is a 5.7 truck starter. The only one that fits the TTI system
 
Don't even feel bad about the reaction time. Deal with those 60ft's!lol IMHO, your 60's should be 1.8 or better, considering your trap speed at the top end, and I think you should be able to run some more RPM out of that Hemi...
 
well, shift point is set at 5500. rev limit is 6500. guess I shift at 6000. not sure yet. :)

caltracs, semi slicks will help I guess for 60'. But those hard launches the clutch won't like. Since you swapped some of the r154 trannies - are there better clutches on the market now fitting the r154? I have still this advanced adapter disc with centerforce dual friction plate since 2006 in .......
 
Buschi i think this bad 60ft time is due to the extreme long Ratios in the Toyota trans.
So you are barely shiftet in 3 gear in the finish, right?
 
Track prep has a lot to do with those times as well. The one time I took my Hemi swap out with the old 4 speed I had a heck of a time getting it to launch, even with street slicks. I think my rear suspension probably had a little to do with that as well as maybe not getting the tires hot enough. I was also right on the edge of hitting 4th at the line. Have meant to take it back now that I did the 6 speed swap and new rear springs and shocks, but just never got around to it this year.
 
Ok so i bought the 2012 challenger rt, it's been rolled but mech sound. Just one exam left next week then onto my next project. Was there anything that dissuaded you from going with the challenger donor.

Sorry for the essay!
Mike
 
Keep in mind also, AMS sells complete front floors, including the center transmission hump. As for the torsion bar crossmember, not that big of deal either. The T-56 looks the best to me too.
 
Will it handle full throttle clutch drops?

Will anything? Reminds me what my grandpa used to say about my brother. "That kid could break a cannon ball."
 
I can almost promise you I will break my 8 3/4 rear before I have a T56 problem. Next year I will hit the track with slicks to see what I mph.
 
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