Eaton/Whipple/KB power band... roll racing.
05-10-2009, 07:04 PM
#1
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Join Date: Nov 2007
Location: Maryland
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Eaton/Whipple/KB power band... roll racing.
Ok so you guys with the twinscrew/roots superchargers. Of those of you who have/do roll race, do you still drop a gear even though you make boost down low? i would think dropping a gear would put u in more boost but you would stop making boost quicker, when do these blowers stop making boost? What do you rev your car to? Just got to thinking today about this after a ride in my buddys 483/460 04 ported/pullied bolt on Cobra, seems like he was never downshifting but he didn't really need to because the blower kicked in so low, i didn't really bother to ask him about it.
05-10-2009, 10:55 PM
#6
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Location: California
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my blower never really stops making boost, at 5000rpm im at 18lbs, and at 6500rpm im at 17.5.. so its pretty consistant.
the eaton does drop boost at high rpm
as far as roll racing though... if its like a 40mph punch, i'll keep it in 2nd and get on it from around 3500 rpm... MAD TORQUE.
the eaton does drop boost at high rpm
as far as roll racing though... if its like a 40mph punch, i'll keep it in 2nd and get on it from around 3500 rpm... MAD TORQUE.
05-12-2009, 11:04 PM
#10
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You can also loose boost because of valvetrain inefficiency, I loose .5-1PSI above 6800RPM, not just because of blower inefficiency
But you still want to shift down so that you're higher in your powerband during a roll race.
On a Auto-x course, and on road courses, you can stay in lower gears coming out of a corner because you don't want too much torque.
But you still want to shift down so that you're higher in your powerband during a roll race.
On a Auto-x course, and on road courses, you can stay in lower gears coming out of a corner because you don't want too much torque.