weird problem kicking my butt on 95 LT1
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Racer
Joined: Apr 2002
Posts: 354
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From: Red Oak TX
weird problem kicking my butt on 95 LT1
I installed an LT4 hotcam in a friends car along with an optispark, plugs, and wires.
After the install the car loses power after 4000 rpms. It runs "okay", but there is a noticeable loss of power. The car will buck at low rpms if you give it more than 25% throttle. The car idles fine, and runs great at cruise.
I've tried a new coil that I had in stock, no effect. I had also replaced the fuel pump, fuel filter, and fuel pressure regulator about 500 miles before the cam swap.
However, fuel pressure is 37 psi at idle. If I take the vacuum hose off the FPR I get fuel pressure at 45 psi which is in spec.
Any ideas?
After the install the car loses power after 4000 rpms. It runs "okay", but there is a noticeable loss of power. The car will buck at low rpms if you give it more than 25% throttle. The car idles fine, and runs great at cruise.
I've tried a new coil that I had in stock, no effect. I had also replaced the fuel pump, fuel filter, and fuel pressure regulator about 500 miles before the cam swap.
However, fuel pressure is 37 psi at idle. If I take the vacuum hose off the FPR I get fuel pressure at 45 psi which is in spec.
Any ideas?
Team Owner
Joined: Sep 2001
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From: Athens AL
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Re: weird problem kicking my butt on 95 LT1 (Blue 02 C5)
I dont know LT1s well, but id be willing to bet you didnt put the cam in exactly right. I remember someone having a problem similar to that and the cam was timed wrong.
Thread Starter
Racer
Joined: Apr 2002
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From: Red Oak TX
Re: weird problem kicking my butt on 95 LT1 (Springer's LT4)
How many miles... Did you put new valve springs in?
Thread Starter
Racer
Joined: Apr 2002
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From: Red Oak TX
Re: weird problem kicking my butt on 95 LT1 (vader86)
I dont know LT1s well, but id be willing to bet you didnt put the cam in exactly right. I remember someone having a problem similar to that and the cam was timed wrong.
Thread Starter
Racer
Joined: Apr 2002
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From: Red Oak TX
Re: weird problem kicking my butt on 95 LT1 (Lone Ranger)
Don't you also need a custom ECM chip (or reprogram and flash a '94 - 96 LT1) to make the engine run optimally with a hot cam?
It really runs fine except under severe load.
Race Director
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Re: weird problem kicking my butt on 95 LT1 (Blue 02 C5)
No, you don't have to program anything for the Hot Cam to perform. It will perform better if you raise the rev limiter and tweak the fuel curves as well as compensate for the louder roller rockers by adding an LT4 Knock Module, but it should still work.
You shouldn't have any stumbles or power gaps, in fact it should really light up above 4000 rpm's and pull hard to the rev limiter which it will find very quickly if it's still in the stock location.
I'll ask what somebody else asked again. Are you SURE the cam is installed properly? I swore up and down that I installed mine properly the second time. I had some of the strangest problems in the world until I took it apart again and found it one tooth out of time.
You shouldn't have any stumbles or power gaps, in fact it should really light up above 4000 rpm's and pull hard to the rev limiter which it will find very quickly if it's still in the stock location.
I'll ask what somebody else asked again. Are you SURE the cam is installed properly? I swore up and down that I installed mine properly the second time. I had some of the strangest problems in the world until I took it apart again and found it one tooth out of time.
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From: Amateur driver on open course.
Re: weird problem kicking my butt on 95 LT1 (Nathan Plemons)
No, you don't have to program anything for the Hot Cam to perform. It will perform better if you raise the rev limiter and tweak the fuel curves as well as compensate for the louder roller rockers by adding an LT4 Knock Module, but it should still work.
You shouldn't have any stumbles or power gaps, in fact it should really light up above 4000 rpm's and pull hard to the rev limiter which it will find very quickly if it's still in the stock location.
I'll ask what somebody else asked again. Are you SURE the cam is installed properly? I swore up and down that I installed mine properly the second time. I had some of the strangest problems in the world until I took it apart again and found it one tooth out of time.
You shouldn't have any stumbles or power gaps, in fact it should really light up above 4000 rpm's and pull hard to the rev limiter which it will find very quickly if it's still in the stock location.
I'll ask what somebody else asked again. Are you SURE the cam is installed properly? I swore up and down that I installed mine properly the second time. I had some of the strangest problems in the world until I took it apart again and found it one tooth out of time.
Thread Starter
Racer
Joined: Apr 2002
Posts: 354
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From: Red Oak TX
Re: weird problem kicking my butt on 95 LT1 (Nathan Plemons)
No, you don't have to program anything for the Hot Cam to perform. It will perform better if you raise the rev limiter and tweak the fuel curves as well as compensate for the louder roller rockers by adding an LT4 Knock Module, but it should still work.
You shouldn't have any stumbles or power gaps, in fact it should really light up above 4000 rpm's and pull hard to the rev limiter which it will find very quickly if it's still in the stock location.
I'll ask what somebody else asked again. Are you SURE the cam is installed properly? I swore up and down that I installed mine properly the second time. I had some of the strangest problems in the world until I took it apart again and found it one tooth out of time.
You shouldn't have any stumbles or power gaps, in fact it should really light up above 4000 rpm's and pull hard to the rev limiter which it will find very quickly if it's still in the stock location.
I'll ask what somebody else asked again. Are you SURE the cam is installed properly? I swore up and down that I installed mine properly the second time. I had some of the strangest problems in the world until I took it apart again and found it one tooth out of time.
It has to be a fuel problem... the car sometimes runs fine, even at WOT. But 75% of the time, it does not.
About the cam timing, I'm 100% sure it's correct. I have been building SBCs and LS1s for years. :)
Race Director
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Re: weird problem kicking my butt on 95 LT1 (Blue 02 C5)
And if I told you that my fuel pressure varies between 36 and 46 while driving would that tell you anything? I'm afraid the Camaro guys just want you to throw parts at it. I've tried that and it's no fun. You can do that until you're broke and blue in the fact and you'll be right where you started from.
If you're sure the cam is timed properly then I don't really know what to say, but I can tell you it's probably not fuel pressure.
If you're sure the cam is timed properly then I don't really know what to say, but I can tell you it's probably not fuel pressure.
Thread Starter
Racer
Joined: Apr 2002
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From: Red Oak TX
Re: weird problem kicking my butt on 95 LT1 (Nathan Plemons)
And if I told you that my fuel pressure varies between 36 and 46 while driving would that tell you anything? I'm afraid the Camaro guys just want you to throw parts at it. I've tried that and it's no fun. You can do that until you're broke and blue in the fact and you'll be right where you started from.
If you're sure the cam is timed properly then I don't really know what to say, but I can tell you it's probably not fuel pressure.
If you're sure the cam is timed properly then I don't really know what to say, but I can tell you it's probably not fuel pressure.
I do appreciate your input, but I feel that this problem has nothing to do with cam or ignition timing. The car will sometimes accelerate fine, and a incorrect cam installation will not show up as an intermittent condition.
Team Owner
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From: Athens AL
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Re: weird problem kicking my butt on 95 LT1 (Nathan Plemons)
I'm afraid the Camaro guys just want you to throw parts at it.
Pro
Joined: Sep 2002
Posts: 500
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From: Mississauga ONT
Re: weird problem kicking my butt on 95 LT1 (Ramrod92)
hook it up to a scanner. its the only way. From my guess......
1) optispark
2) balancer (causing the opti to vibrate)
3) knock sensors
4) MAF sensor malfunctioning
5) Thtottle postion sensor needs adjusting
6) Throttle cable.
1) optispark
2) balancer (causing the opti to vibrate)
3) knock sensors
4) MAF sensor malfunctioning
5) Thtottle postion sensor needs adjusting
6) Throttle cable.
Thread Starter
Racer
Joined: Apr 2002
Posts: 354
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From: Red Oak TX
Re: weird problem kicking my butt on 95 LT1 (388 SOLid RoLLeR)
hook it up to a scanner. its the only way. From my guess......
1) optispark
2) balancer (causing the opti to vibrate)
3) knock sensors
4) MAF sensor malfunctioning
5) Thtottle postion sensor needs adjusting
6) Throttle cable.
1) optispark
2) balancer (causing the opti to vibrate)
3) knock sensors
4) MAF sensor malfunctioning
5) Thtottle postion sensor needs adjusting
6) Throttle cable.
2) will check this one
3) already checked with my scanner, no knock retard present
4) checked out okay
5 and 6) checked out okay.
