PatientZero
@restless_performance
Does anyone have experience using a restrictor plate to kill power? My goal over the next year is to start running SCCA Time Trials in Midiv. The way my car sits I'd be well into Prod E territory. 3240lbs with driver/fuel, 480whp. I'd like to get back down into Prod D. With the allowed ballast of 150lbs I'd still need to get down to 440whp. This is probably a little bit more than I can kill in the tune. Ideally I don't want to add any weight and get the car down to 415-420whp. I'm thinking a restrictor plate would be the best way to do it. I haven't been able to find a great deal of information outside of using them on carbureted motors. I'm curious about placement and tuning.
On the Corvette C5.R the restrictor plate was in the intake tubing right in front of the intake plenum for the ITB's. I'm thinking I could probably fab something up to go in this area. The other question is tuning. Should you tune before or after? The only info I found said to tune the motor uncorked first and then add the appropriate sized restrictor plate to kill horsepower. Does anyone have experience with them and can confirm? Also, could the throttle body be adjusted so it doesn't open completely?
I would ask my tuner or engine builder but in both cases that is also me, so...?
On the Corvette C5.R the restrictor plate was in the intake tubing right in front of the intake plenum for the ITB's. I'm thinking I could probably fab something up to go in this area. The other question is tuning. Should you tune before or after? The only info I found said to tune the motor uncorked first and then add the appropriate sized restrictor plate to kill horsepower. Does anyone have experience with them and can confirm? Also, could the throttle body be adjusted so it doesn't open completely?
I would ask my tuner or engine builder but in both cases that is also me, so...?
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