Join Date: Jul 2006
Location: Valrico Florida
I have the same car only stock build. Go with the pressure checks first. Also, check fuel delivery. My experience has been if the pressure drops off under load, the mixture goes rich. I'm assuming the reduction in control pressure has a greater influence on the delivered results than the reduction of supply pressure. My car was rich @ idle, lean under acceleration, rich under initial boost then buck horribly when it ran out of fuel on the top end. My recommendation is to eliminate fuel delivery first before making any adjustments or repairs to any other component. I'm replacing the failed rear pump on my car now, which caused my lack of delivery volume. Once that's done, I'll be faced with undoing all the other adjustments made that have been a compromise for lack of fuel. Your car needs at least 1170 cm in 30 seconds with a stock build. Your build will probably require about 1500cm in 30 seconds. I can explain the test procedure if you are not familiar but I won't bore you with the details now in case you already know. My car was delivering 1000cm when my problem arose. That's enough fuel for about 260hp gross. Anything over that, you'll hit the limits.
'77 930 turbo Garretson I/C 1 BAR spring, (2) '82 Triumph Bonneville Royal Wedding Edition
Past rides: '74 914 1.9 liter twin plugged track car, '83 928S, '87 924S, '75 911S w '78 ROW 3.0, '72 911T, '70 911T and various other insignificant domestic examples. Happiness is a grey tailpipe! Turbo lag......it's worth the wait!