First off, here is a link to a video that we did that outline some of the installation and some of the features of the T56 Magnum:
http://www.youtube.com/watch?v=1oXQG96aNL
In the process of building several cars over the last 30 years, most recently the 48 Hour Camaro, I have had the opportunity to use many different engine and transmission combinations. MOST have turned out very well. Ive had great success with the 700R4, especially with a manual valve body and a Gear Vendors overdrive unit in our 66 Chevelle on the autocross and road course. Ive used a 4L60 and a 4L80 automatic in a couple of cars with similar success. Velocity had a ZF 6 speed which I loved!
When we started planning the 48 Hour Camaro the criteria was simplicity and ease of installation, along with durability and performance. This led us to try a plain old Muncie M21 4 speed with a Gearvendors overdrive unit. I must say I really enjoyed that combination on the street and on the track. The ability to toggle between direct and overdrive by pushing a button on the shifter knob was almost an unfair advantage on the autocross and road course, and the 22% overdrive made highway use a breeze. The shifting precision was certainly above adequate and it went into the car with no modifications whatsoever.
Unfortunately, the Muncie just wasnt up to the use [abuse?] that I gave it on the road course. I kept shucking the teeth off third gear. After the third unit I went to a Tex Racing T101a that I had laying around for another project. This was a great racing transmission
clutchless shifting up and down, light, efficient
but with the straight cut gears it made more noise in the car than any mechanical device Ive ever seen. People would watch the car run and wonder what the hell was wrong with it! Its other sin was that there was no adapter available for the Gearvendors overdrive unit, so highway driving was a high RPM chore. I ended up chipping a tooth on second gear at the Texas Goodguys event so I had yet another decision to make.
Why didnt I simply go with a T56 Magnum in the first place, you ask? Well, there were several reasons. During the planning stages of the car I couldnt seem to find a decent supplier for such a unit [I hadnt met the guys from American Powertrain yet]. Also, I had a fairly poor experience with the TKO series Tremec units previously and wanted to explore other alternatives.
After I hurt the Tex unit in Texas I had to make something happen fairly quickly because I was scheduled to race at the Optima Ultimate Street Car Invitational right after SEMA. Over the summer I had come to know the guys at American Powertrain who have developed a VERY complete system for installing both the TKO and the T56 Magnum into these musclecars. We actually used their bellhousing/clutch/master cylinder/throwout bearing in the 48 Hour Camaro build to install the Muncie. Good people
great products.
Matt Graves, Grey Fredrick, and Robert Hall from American Powertrain had been teasing me all summer about my transmission problems with the Camaro and said anytime I wanted to come in from the rain they could set me up with a nice T56 Magnum. While I was still in Texas, I texted Matt and said: Tex broke. Bring me a T56. So they did.
Matt and Grey swore and be damned that the T56 would go in that Camaro without cutting the floorpan. If it werent for the fact that I was using half height body bushings, and that we had moved the engine back by about an inch
they would have been exactly right. Even with all of my previous customizations we just cut the top of the trans tunnel out and made a new one. It just wasnt that big a deal. The T56 is not really much smaller than the TKO, but the top is shaped differently so its actually a much better fit in any given trans tunnel. The video that we made [linked] gives you an overview of some of the features and benefits of that transmission
I wont repeat them here. I do, however, want to offer an evaluation of this transmission from a hotrodders perspective.
I had MANY reliable people tell me about the virtues of the T56
Brian Finch, Mark Steilow, Steven Rupp, Mike Copeland
these are guys who flog their cars regularly and have no agenda for or against this transmission.
Grey Fredrick from American Powertrain had to teach me how to shift. [youll see this in the video] At 50 years old with well over 30 years of hotrodding experience behind me, I found it a little hard to believe that I didnt know everything there was to know about shifting a dumb old transmission. Heres the lesson: An open mind will make your car faster.
The T56 is to be shifted with 2 fingers, not your whole fist. If you try to rape this thing it will seem sticky and notchy. It shifted fast
VERY fast, at any RPM I tried it at
IF you treat it like a partner instead of a servant. Its not tricky at all, its more of a mindset. I love the ratio spread
its never hard to keep the engine in an appropriate RPM range. I love the tall 6th gear as well. On the way to Pahrump from Vegas for the Optima event we were running
well, never mind how fast we were running. The engine was at about 3100 RPM in 6th gear with a 26 tall tire and a 3.50 gear. You figure it out. The point is that ANY reasonable [or unreasonable] highway speed is much less stressful with the T56 Magnum 6 speed.
In addition to the raw performance of the T56 Magnum, I have to comment on the service and installation kit from American Powertrain. While it is possible that I experienced wonderful service because of our personal and professional relationship, I have heard similar accolades from many other American Powertrain customers. It is a simple matter of you call..they deliver. In the end, thats all any of us want, right?
The installation kit was as complete as any product Ive seen. The bellhousing, hydraulic throwout bearing, clutch, pilot bearing, driveshaft yoke, crossmember
it was all there and very elegantly made. The crossmember was really unusual
its a nicely formed piece of 6061-T6 aluminum that looks kind of like a wing. Unfortunately we could not use it in our installation because of the dropped body mounts and the engine setback. Bummer.
The other item that I wanted to point out again [youll see this in the video] was the unique shifter system. It is adjustable not only for position on the trans, but the position of the shifter handle on the plate as well. In addition, the tension of the shifter is externally adjustable
you can actually adjust with a screwdriver the spring tension that centers the shifter between gears. I like this a LOT!
I still miss my Gearvendors overdrive, but this T56 Magnum 6 speed from American Powertrain is getting me over my grief nicely.
