Need Opinions
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From: Thonotosassa Florida
Need Opinions
I recently had a G5X3 on 114 LSA cam package with ASP underdrive pulley installed on my 02 Z06. The car also has LGM longtubes, Stingers, Random cats and Halltech Stinger. After several dyno runs, all in about the same ballpark, the best my tuner could do is 404 HP and 360 TQ. I really thought I would be closer to 425 HP and 400 TQ. My tuner tried adjusting everything with no luck. The car just would not respond. I am looking for your expert opinions as to what could be going on here. The car has never been abused or raced.
Racer
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hmm... I have a 99 FRC also with the G5X3 on a 114. With the cam (comp 921 springs, chromoly pushrod, titanium retainers), LG longtubes (no cats), My car put down 380 rwhp and 372 rwtq. I since then added borla stinger and a donaldson blackwing. Not sure what Im putting down now, maybe. I figured you would have at least 430 rwhp. Was your car dynoed at 8000 feet??? 
Drifting
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From: Chapin SC
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I'm not familiar with the G5X3 specs but on the LGMotorsports web site they mention making 415hp with LG Pro Longtubes, & Corsa Cat-back with the G5X3 cam and exhaust only. You didn't mention what valve springs that you're using. Most of the popular LS1/LS6 cams make the big power gains in the upper RPM ranges so to take full advantage of your cam you need to spin your motor up to around 7K. This requires upgraded valve springs and re-setting the PCM rev-limiter. Another thing to look at is the attachment of your air filter to the air duct. A couple of years ago Cartek showed me where my Halltech Sidewinder filter was slightly cocked; this generated turbulence that cost 15 peak horsepower. That's not an estimate I watched the before and after dyno runs that were conducted within 15 miunuts of each other.
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From: Thonotosassa Florida
Originally Posted by JerryL
I'm not familiar with the G5X3 specs but on the LGMotorsports web site they mention making 415hp with LG Pro Longtubes, & Corsa Cat-back with the G5X3 cam and exhaust only. You didn't mention what valve springs that you're using. Most of the popular LS1/LS6 cams make the big power gains in the upper RPM ranges so to take full advantage of your cam you need to spin your motor up to around 7K. This requires upgraded valve springs and re-setting the PCM rev-limiter. Another thing to look at is the attachment of your air filter to the air duct. A couple of years ago Cartek showed me where my Halltech Sidewinder filter was slightly cocked; this generated turbulence that cost 15 peak horsepower. That's not an estimate I watched the before and after dyno runs that were conducted within 15 miunuts of each other.
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From: Thonotosassa Florida
Originally Posted by JetVette01
hmm... I have a 99 FRC also with the G5X3 on a 114. With the cam (comp 921 springs, chromoly pushrod, titanium retainers), LG longtubes (no cats), My car put down 380 rwhp and 372 rwtq. I since then added borla stinger and a donaldson blackwing. Not sure what Im putting down now, maybe. I figured you would have at least 430 rwhp. Was your car dynoed at 8000 feet???
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From: Thonotosassa Florida
Originally Posted by Mitch C
Are you sure the cam was installed correctly? It might be installed one tooth retarded or advanced. How good is your tuner? Perhaps a different tuner can get more out of your car. 
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From: Thonotosassa Florida
Originally Posted by Darkness
Just how good is your tuner and you trust his work? Is he known? I'm sure its in the tune.
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From: Thonotosassa Florida
Originally Posted by Nick 02 Z06
What did your air fuel look like at WOT? I have a feeling this has something to do with the stinger. I wonder what would happen if you swapped in a 01 Z06 maf...
, Goto Norris in orlando they do great work.
Drifting
Joined: Mar 2001
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From: Pensacola FL
I had a similar experience last fri at my dyno. I ran a totally different cam, but was able to pull a best of 388rwhp & 371 TQ. I was hoping for a little closer to 400. My car also did not respond well to anything we tried. We added 4 deg of timing and still got no KR, but gained almost no add'l power. Tried leaning it a bit more, but marginal results. To be safe we backed things off a little, and only lost less than 2hp. I put the cam in myself, and it would be pretty easy to tell if you were a tooth off by referencing the dots. Not saying that couldn't happen, but to the eye, it is easily detectable. Let us know what you find out. Scott
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From: Thonotosassa Florida
Originally Posted by 99 The Hard Way
I had a similar experience last fri at my dyno. I ran a totally different cam, but was able to pull a best of 388rwhp & 371 TQ. I was hoping for a little closer to 400. My car also did not respond well to anything we tried. We added 4 deg of timing and still got no KR, but gained almost no add'l power. Tried leaning it a bit more, but marginal results. To be safe we backed things off a little, and only lost less than 2hp. I put the cam in myself, and it would be pretty easy to tell if you were a tooth off by referencing the dots. Not saying that couldn't happen, but to the eye, it is easily detectable. Let us know what you find out. Scott
I am now in the process of finding out what it is going to cost me to check on the tooth issue with my tuner. This is driving me nuts. 360 TQ numbers is too low and something has to be wrong. I had more torque of 370 TQ with just my header install.
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From: Indianapolis Indiana
St. Jude Donor '11
Hey All,
We did the install here and are working with Tom to see what is up. The car is making the same torue at peak (359.9 prveious, 360.4 after), not 10 less. But it did pick up 30RWT from 3700 and down. The HP picked up 30-35RW starting to gain at 5500RPM. There is 29* timing, 12.8-13.1 to 1 on the A/F and no detonation. Definitely odd as most big cams off one tooth may run well, but usually lose 10-20 RWT & RWHP over stock.
I let Tom know that if it was one tooth of that we would take care of the resetting of the timing gears along with the assciated retune. I find it hard to see that it could be off a tooth, but dumber things have happened for sure. Maybe the cam if ground improper or not what it was supposed to be. Hard to tell with no cam card and serial numbers ground off. The car did run well previously and we are using the same stock timing set, so that should not be a problem. We will eventually see what we can do, just trying to align with Tom an a time. Later.
Mike Norris
We did the install here and are working with Tom to see what is up. The car is making the same torue at peak (359.9 prveious, 360.4 after), not 10 less. But it did pick up 30RWT from 3700 and down. The HP picked up 30-35RW starting to gain at 5500RPM. There is 29* timing, 12.8-13.1 to 1 on the A/F and no detonation. Definitely odd as most big cams off one tooth may run well, but usually lose 10-20 RWT & RWHP over stock.
I let Tom know that if it was one tooth of that we would take care of the resetting of the timing gears along with the assciated retune. I find it hard to see that it could be off a tooth, but dumber things have happened for sure. Maybe the cam if ground improper or not what it was supposed to be. Hard to tell with no cam card and serial numbers ground off. The car did run well previously and we are using the same stock timing set, so that should not be a problem. We will eventually see what we can do, just trying to align with Tom an a time. Later.
Mike Norris
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From: Thonotosassa Florida
Originally Posted by CJS
With no cam card and the serial ground off I would have never put that "whatever it is cam" in my car.