Steve went back to the drawing board and decided to build a front mount Twin Turbo. We had the built 402 Ci LQ9 still in the car so we chose to go with the Precision 6266 Turbos, sacrificing future growth for faster spool. Our objective was not to make the most horsepower, just to create a good performance package that could bolt onto a GTO with minimum addition modifications and as little cutting on the car as possible. The turbos were Precision T4 6266 with a .96 a/r and a ported S cover. The package made 1145 rwhp and 1269 rwtq right out of the box. The Convertor that had been built for the supercharger was slipping as much as 40% and we had a great deal of trouble keeping both turbos running. Needless to say the car had a lot more in it. We had about 4 brand new Precision units fail and the convertor issue was difficult to deal with. The wear on the crank from the Whipple timing issues eventually loosened and separated the reluctor wheel. Before the damage was obvious we did get a track day and ran 6.32 @ 112 in the 1/8 mile. That was on a failing turbo and the slipping convertor. We pulled the LQ9 out and sent the Precision units to Reed at Works Turbocharger to be rebuilt. When we discovered the crank was ruined on theĀ  LQ9, I decided to upgrade to an LSx to take advantage of the 6 bolt cathedral port heads I already had.

TT LQ9 on the Dyno

Best Pass

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