Cant get car to make power past 5000 rpm
10-09-2008, 08:53 PM
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Cant get car to make power past 5000 rpm I got a 383 LT1 with a F1A blower on it. Went to dyno it today and ran into some problems:
1) the car gets up to about 5000 rpms and then its basically like you just turn the key off. your foot is still on full throttle yet the car just drops back to about 2000 rpms. This is only at about 6 psi...so id assume the inlet isnt being sucked shut. Fuel pressure is up around 50 at WOT. Ignition box rev limiter is set at 6500. Anybody have this type of problem before?
2) the car isnt even making boost until 4500-5000 rpms....could this be caused by the bypass valve opening too soon? We didnt have time to really check but i figure that is what it would have to be.
Its frusterating because the car is so close to being able to run down the track....but these little problems. Im starting to think it may be in the tune because everything we looked at seemed to check out alright mechanically.
any input would be greatly appreciated
1) the car gets up to about 5000 rpms and then its basically like you just turn the key off. your foot is still on full throttle yet the car just drops back to about 2000 rpms. This is only at about 6 psi...so id assume the inlet isnt being sucked shut. Fuel pressure is up around 50 at WOT. Ignition box rev limiter is set at 6500. Anybody have this type of problem before?
2) the car isnt even making boost until 4500-5000 rpms....could this be caused by the bypass valve opening too soon? We didnt have time to really check but i figure that is what it would have to be.
Its frusterating because the car is so close to being able to run down the track....but these little problems. Im starting to think it may be in the tune because everything we looked at seemed to check out alright mechanically.
any input would be greatly appreciated
10-09-2008, 09:30 PM
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Well im pretty sure somethings going on with the bypass valve because this thing should be making boost well below 4500 rpms...but i wouldnt think that would have anything to do with the engine shuting itself down at 5000 rpms.
Belt is beyond tight so i cant imagine it would be slipping....especially at such a low boost on a 12 rib pulley...something to look at though i guess
Belt is beyond tight so i cant imagine it would be slipping....especially at such a low boost on a 12 rib pulley...something to look at though i guess
