turboandrew
Member
- Messages
- 571
- Location
- Austin, TX
OK, making good progress on the adapter to mate the Getrag 6 speed found in 1993-1998 Toyota Supra Turbos to the 1/2/3UZ engine. First, some background:
My original intention was to mill of the existing flange on the 6 speed, have a new flange CNC milled to match the V8, then weld on the new flange to the 6 speed. I finally decided against this because the flange was going to end up really thick (1.75") and I was concerned about welding the flange. If I ever decided to make more of these and sell them, I didn't think asking the buyer to mill off the old flange and have the new one placed in a precise manner (ususally take a spare block with the rear side facing up) and welded would be practical. So , I worked on a new design which doe snot require any welding at all.
Luckly, the space needed between the 6 speed and the V8 is an extra 3/4". This is because the inline 6 (2JZGTE) has a flange which sticks out 3/4" more relative to the end of the crankshaft, compared to the V8. In order to have the input shaft in the right place, abot 1/2" in the pilot bearing, one needs 3/4" gap between the V8 and the 6 speed. This was a perfect opportunity to make an adapter plate that accepts the two different bolt patterns.
One (big) problem: at least four of the bolt holes on both the V8 and the 6 speed overlap. It is not possible to have both parts bolt into or through a common adapter plate. The bolts would run right into each other. You could rotate the transmission over a bit, but I found that totally unacceptable. I did not want the shifter angle to change and I did not want to redesign the transmission mount. So, after some brainstorming, I came up with a new adapter: A two piece adapter.
The adapter is not complete, but I am very close. The idea is to have the bolts which overlap go through just one plate. Where that happens, there will be other bolts, not used to bolt the tranny/V8 together, but to hold the two plates together. In other areas where the V8/tranny bolts do not overlap, any given bolt will use both plates. On the engine bolt patten, the bolt will go through both plates ( the bolt head is recessed in the "top" plate), and threaded into the engine. On the tranny, the bolt will go through the transmission, the "top" plate, the be threaded into the "bottom" plate.
Take a look at the four pictures. On the second one, the bottom plate is mounted. Now, four bolts from each of the V8 and tranny overlap here. So, the four bolts for the V8 (two on top, two on bottom) go though the bottom plate (the heads are recessed to not interfere with the top plate) and threaded into the V8. On the third photo, the top plate is installed, and the remaining V8 bolts are installed (all heads recessed). On the fourth picture, the tranny is installed. The four bolts on the top and bottom of the tranny are the ones which overlap, so they go through the tranny and are threaded into the top plate. Now, in those areas, there will be some extra bolts which hold the two plates securely together. Finally, all of the other tranny bolts go through the tranny, through the top plate, and are threaded into the bottom plate. That's about it!
I still need to drill and tap all the tranny bolt holes/threads, so don't go looking for them yet! I need to get a couple of drill bits and taps this week, so hopefully next weekend I can get this done!
Final picture is the mill in action. It an take a loooong time to cut a 3/4" deep circle!
My original intention was to mill of the existing flange on the 6 speed, have a new flange CNC milled to match the V8, then weld on the new flange to the 6 speed. I finally decided against this because the flange was going to end up really thick (1.75") and I was concerned about welding the flange. If I ever decided to make more of these and sell them, I didn't think asking the buyer to mill off the old flange and have the new one placed in a precise manner (ususally take a spare block with the rear side facing up) and welded would be practical. So , I worked on a new design which doe snot require any welding at all.
Luckly, the space needed between the 6 speed and the V8 is an extra 3/4". This is because the inline 6 (2JZGTE) has a flange which sticks out 3/4" more relative to the end of the crankshaft, compared to the V8. In order to have the input shaft in the right place, abot 1/2" in the pilot bearing, one needs 3/4" gap between the V8 and the 6 speed. This was a perfect opportunity to make an adapter plate that accepts the two different bolt patterns.
One (big) problem: at least four of the bolt holes on both the V8 and the 6 speed overlap. It is not possible to have both parts bolt into or through a common adapter plate. The bolts would run right into each other. You could rotate the transmission over a bit, but I found that totally unacceptable. I did not want the shifter angle to change and I did not want to redesign the transmission mount. So, after some brainstorming, I came up with a new adapter: A two piece adapter.
The adapter is not complete, but I am very close. The idea is to have the bolts which overlap go through just one plate. Where that happens, there will be other bolts, not used to bolt the tranny/V8 together, but to hold the two plates together. In other areas where the V8/tranny bolts do not overlap, any given bolt will use both plates. On the engine bolt patten, the bolt will go through both plates ( the bolt head is recessed in the "top" plate), and threaded into the engine. On the tranny, the bolt will go through the transmission, the "top" plate, the be threaded into the "bottom" plate.
Take a look at the four pictures. On the second one, the bottom plate is mounted. Now, four bolts from each of the V8 and tranny overlap here. So, the four bolts for the V8 (two on top, two on bottom) go though the bottom plate (the heads are recessed to not interfere with the top plate) and threaded into the V8. On the third photo, the top plate is installed, and the remaining V8 bolts are installed (all heads recessed). On the fourth picture, the tranny is installed. The four bolts on the top and bottom of the tranny are the ones which overlap, so they go through the tranny and are threaded into the top plate. Now, in those areas, there will be some extra bolts which hold the two plates securely together. Finally, all of the other tranny bolts go through the tranny, through the top plate, and are threaded into the bottom plate. That's about it!
I still need to drill and tap all the tranny bolt holes/threads, so don't go looking for them yet! I need to get a couple of drill bits and taps this week, so hopefully next weekend I can get this done!
Final picture is the mill in action. It an take a loooong time to cut a 3/4" deep circle!
