96 Z28 lagging in the upper RPMs?
04-07-2012, 03:06 PM
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96 Z28 lagging in the upper RPMs? I have a 96 z28 that I just bought. The car has 139k miles on it. The rebuilt LT1 has 8k miles on it. The guy was very organized and had every reciept of every aftermarket purchase/installation. The car has after market 26 lb injectors, forged rods, after market flat top pistons, aftermarket eagle crankshaft, beehive springs, a 510 lift comp cam, electric water pump, hookers headers, a full magnaflow exhaust system and more. Now the car has yet to be tuned since the rebuild...Could this be the cause of the leg, and lack of power? The car is running pretty damn rich..I am currently saving to put it on a dyno. The car also is suffering a decent exhaust leak from the headers. Could that cause any problems? Please help me out, as I am new to the lt1. Thank you
04-07-2012, 03:12 PM
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it could be just that it is an LT1....
seriously though, describe the what the motor is actually doing.... missing, slow rpm climb, sound, rpm where it starts, when the motor is hot/cold.... etc
seriously though, describe the what the motor is actually doing.... missing, slow rpm climb, sound, rpm where it starts, when the motor is hot/cold.... etc
04-07-2012, 03:16 PM
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The rpms will climb good until like 4500 rpms, then it will leg for a half second, climb to 5ish lag for another half second, climb to 5500 and repeat. Only if I get on it. Its not slipping because the rpms freeze while its lagging..
04-07-2012, 03:27 PM
#4
Stock tuning is rich in PE mode(hard throttle), the problem is further compounded by putting larger injectors on with a stock program, the problem is probably the combination of stock programming and bigger injectors. You should not even be driving it. Obviously 26lbs is not enough to do any damage quickly but had he put 30lbs on it without reprogramming you probably would have ruined the engine long ago. Change the oil often till you get the programming sorted out.
Organized is one thing, having a clue is another, bet the crank is cast which is weaker than stock.
If he did things as stupid as driving a cammed car on a stock tune, OR putting larger injectors on without reprogramming EACH would be a big red flag to stay away from the car. Good luck.
Organized is one thing, having a clue is another, bet the crank is cast which is weaker than stock.
If he did things as stupid as driving a cammed car on a stock tune, OR putting larger injectors on without reprogramming EACH would be a big red flag to stay away from the car. Good luck.
04-16-2012, 05:22 PM
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Stock tuning is rich in PE mode(hard throttle), the problem is further compounded by putting larger injectors on with a stock program, the problem is probably the combination of stock programming and bigger injectors. You should not even be driving it. Obviously 26lbs is not enough to do any damage quickly but had he put 30lbs on it without reprogramming you probably would have ruined the engine long ago. Change the oil often till you get the programming sorted out.
Organized is one thing, having a clue is another, bet the crank is cast which is weaker than stock.
If he did things as stupid as driving a cammed car on a stock tune, OR putting larger injectors on without reprogramming EACH would be a big red flag to stay away from the car. Good luck.
Organized is one thing, having a clue is another, bet the crank is cast which is weaker than stock.
If he did things as stupid as driving a cammed car on a stock tune, OR putting larger injectors on without reprogramming EACH would be a big red flag to stay away from the car. Good luck.
