[Purdue3KGT]

I don't think reliability would take TOO much of a hit. Obviously when you add more moving parts it complicates the equation... but I do think we have a fairly stout base to start from. As mentioned before, the stock CR of the SOHC is 8.9:1. That is just a tad over the 8.5:1 of the TT's. I would say 7-8 PSI on a decent single would be fine.

This is where the making more performance parts for the SOHC takes root. Adding cams, cam gears, intake plenums, exhaust manifolds can really give some decent numbers. I would "speculate" to say that a single turbo SOHC running 7-8 pounds could hang with a stockish to almost BPU TT. The main issue with turboing is traction. FWD and turbo don't usually work too well. An LSD, Solid motor mounts, and wide slicks are almost necessary to plant any of the power.

Overall, it WOULD cost a decent amount of money, probably more than if you just sold the car and bought a VR4. The goal is to make something fun that you enjoy working on and have the pride and joy of saying "you made it." I can only think of 1-2 single turbo SOHCs EVER. How many twin turbos are there out there?