Broncobowsher
Total hack
- Joined
- Jun 4, 2002
- Messages
- 35,630
OK, I want to toss out a few thoughts out there. With that much power, and more coming, I have a few worries. While the engine makes the torque, the transmission(s) multiply it. But the torque that is grown in the gearboxes is anchored with the motormounts. But to get there it goes through the bellhousing. I can remember a friend with a high HP car (that doesn't have nearly as much torque growth in the transmission) tearing up a bellhousing.
Now I know the ZF is a stout transmission. But you are looking at putting double, triple(?) the torque INTO the transmission. Now with extra reduction in the transfer case the output torque will be several times what the ZF originally handled. Remember the Newton's lay about equal and opposite reactions? The driveshaft will have, lets call it 2000 Ft-lbs of torque. Lets say 10:1 gear reduction in the transmission (easy math) and the engine at light throttle making only 200 ft-lb of output. As a package the engine/trans/transfer case are taking the opposite of the driveshaft torque, 2000 ft-lb trying to lift the drivers side motor mount. But the engine is only making 200 ft-lb. If you separated the engine and the transmission, think of a divorced transfer case, the engine will be making 200 ft-lb. The reaction is the engine is only trying to lift the drivers motor mount by 200 ft-lb of torque. Wait, wasn't that 2000 with the transmission attached? Yes! The transmission is trying to twist at 1800 ft-lb of reactionary torque. Normally that goes through the bellhousing.
Now think of how much power you are making. I would strongly look at trying to contain that torque at the transfer case. To try and keep the transmission from twisting up. And twist they can. I worked with a guy who had a hot rod tri five chevy with a 4-speed. He managed to twist (but not break) the transmission case. Threw the gears out of alignment. Lets just say the transmission never worked right and it took a long time to figure out why. I know he didn't have nearly the power you have.
Now I know the ZF is a stout transmission. But you are looking at putting double, triple(?) the torque INTO the transmission. Now with extra reduction in the transfer case the output torque will be several times what the ZF originally handled. Remember the Newton's lay about equal and opposite reactions? The driveshaft will have, lets call it 2000 Ft-lbs of torque. Lets say 10:1 gear reduction in the transmission (easy math) and the engine at light throttle making only 200 ft-lb of output. As a package the engine/trans/transfer case are taking the opposite of the driveshaft torque, 2000 ft-lb trying to lift the drivers side motor mount. But the engine is only making 200 ft-lb. If you separated the engine and the transmission, think of a divorced transfer case, the engine will be making 200 ft-lb. The reaction is the engine is only trying to lift the drivers motor mount by 200 ft-lb of torque. Wait, wasn't that 2000 with the transmission attached? Yes! The transmission is trying to twist at 1800 ft-lb of reactionary torque. Normally that goes through the bellhousing.
Now think of how much power you are making. I would strongly look at trying to contain that torque at the transfer case. To try and keep the transmission from twisting up. And twist they can. I worked with a guy who had a hot rod tri five chevy with a 4-speed. He managed to twist (but not break) the transmission case. Threw the gears out of alignment. Lets just say the transmission never worked right and it took a long time to figure out why. I know he didn't have nearly the power you have.