Transaxle selection and Rear tire size
I'm already starting to work on my build. I spent a good part of today looking for a transaxle. I also reviewed the posts in this forum about the G50 variations and modifications to guide my purchase.
From your posts, it appears that nearly all the non-turbo 5 speed G50s are geared for the low torque available at low RPMs of the Porsche boxer 6. In contrast, the GM LS3 has gobs of torque down low. That means the 1st gear is so low its almost unusable and top gear (5th) spins the engine at 2500RPM at 65MPH.
One solution is to make all gear ratios higher by swapping the ring & rinion from 3.44 to 3.10. That would put 5th just about where it should be for freeway cruising. However, cost is a problem. The parts are $2800! That blows my mind since American ring & pinions cost just $150. On top of that, the installation is another $1100. So, the cost of a 5 speed G50 plus the 3.10 ring & pinion swap approaches the price of a G50 6 speed.
I just ordered the SLC yesterday and I'm feeling Po' already!
Another thought is to increase the diameter of the rear wheels. This won't completely resolve the problem, but it will make it marginally better. I saw in this forum where some builders are using 325/30/19 tires.
- Is 325/30/19 the recommended size?
- What's the tallest tire can I stuff in the rear wheel wells? There is plenty of meat on 325/30/19 tires, so I would be willing to go a little narrower to get some height.
- Is there a transaxle you can recommend that won't break the bank?