2000 SS vs 1999 z28
#22
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Before you go swapping pcm's make sure the gear ratios in the cars are the same or else they wont shift correctly. the ss will jhave gu5 on the door code and 3.23's out back the z28 if equipped with the gu5 door code will have 3.23s and an aluminum ds if it has a steel ds then its gu2 and 2.73's.
also the ss doesnt look like its missing anything. the car looks to have acme but its not oem so there may not be a valvence. check on the passenger door for the slp installed options on the car and see what it lists
also the ss doesnt look like its missing anything. the car looks to have acme but its not oem so there may not be a valvence. check on the passenger door for the slp installed options on the car and see what it lists
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if your real ? is you'd like to add a few parts to run faster than your dad after getting a tune A/F 13.0:1 make sure you have an air lid. flip yours over if open and smooth your good if hard plastic baffles bad. then cold / ram air or free ram air. an underdrive pulley plus overdrive alternator pulley & belts maybe $250 that may add 5-10 rwhp. if tractions an issue aka wheelhop lca's . checkout a ported throttle body maybe 5 rwhp. just my one cent.
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Before you go swapping pcm's make sure the gear ratios in the cars are the same or else they wont shift correctly. the ss will jhave gu5 on the door code and 3.23's out back the z28 if equipped with the gu5 door code will have 3.23s and an aluminum ds if it has a steel ds then its gu2 and 2.73's.
Both will be 3.42 (GU6) gears unless modified.
Stock tire diameter for the Z28 was 25.65" and for the SS 25.66", so each tach should read exactly the same unless one has non-stock sized tires or had a gear swap at some point.
#29
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I cleaned the maf and the iat sensor.
I finished replacing all the plugs and wires. half the plugs were changed and the "hard" ones were probably still the stock ones... so I replaced them all... and new stock wires.
I found the exhaust leak, its right above the cat converter after the manifold. weird places to get a crack, anyone seen that before on ls1s?
the door doesn't have any stickers on it so I couldn't check any codes.
the SS runs pretty good now other than the exhaust leak, some lean poping from it.little bit of a rough idle, but I hope it clears up once the exhaust leak is fixed. was getting a code for the cat not working probably because of the leak.
I will try to fix it tomorrow, just going to pull off that part of the exhaust and weld whatever crack I find
I finished replacing all the plugs and wires. half the plugs were changed and the "hard" ones were probably still the stock ones... so I replaced them all... and new stock wires.
I found the exhaust leak, its right above the cat converter after the manifold. weird places to get a crack, anyone seen that before on ls1s?
the door doesn't have any stickers on it so I couldn't check any codes.
the SS runs pretty good now other than the exhaust leak, some lean poping from it.little bit of a rough idle, but I hope it clears up once the exhaust leak is fixed. was getting a code for the cat not working probably because of the leak.
I will try to fix it tomorrow, just going to pull off that part of the exhaust and weld whatever crack I find
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Seems that you are finding several issues that will likely add up to equal the power loss in question.
That exhaust leak near the front O2 sensor will need to be fixed to ensure proper O2 readings and thus fueling.
Once all of these things are taken care of, the car should run much better.![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
No need to check any door codes to verify stock gears. Every M6 LS1 car (trim level doesn't matter) came with 3.42s, so your SS and Z28 both had those gears stock. If one of them had a swap at some point, the door codes obviously couldn't indicate that anyway.
That exhaust leak near the front O2 sensor will need to be fixed to ensure proper O2 readings and thus fueling.
Once all of these things are taken care of, the car should run much better.
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No need to check any door codes to verify stock gears. Every M6 LS1 car (trim level doesn't matter) came with 3.42s, so your SS and Z28 both had those gears stock. If one of them had a swap at some point, the door codes obviously couldn't indicate that anyway.
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99 egr mod scroll down to photo#6 to see what im talking about. http://www.installuniversity.com/ls1...r/ls1-egr.html
#35
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OP already stated that both are M6s so none of this would apply.
Both will be 3.42 (GU6) gears unless modified.
Stock tire diameter for the Z28 was 25.65" and for the SS 25.66", so each tach should read exactly the same unless one has non-stock sized tires or had a gear swap at some point.
Both will be 3.42 (GU6) gears unless modified.
Stock tire diameter for the Z28 was 25.65" and for the SS 25.66", so each tach should read exactly the same unless one has non-stock sized tires or had a gear swap at some point.
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I cleaned the maf and the iat sensor.
I finished replacing all the plugs and wires. half the plugs were changed and the "hard" ones were probably still the stock ones... so I replaced them all... and new stock wires.
I found the exhaust leak, its right above the cat converter after the manifold. weird places to get a crack, anyone seen that before on ls1s?
the door doesn't have any stickers on it so I couldn't check any codes.
the SS runs pretty good now other than the exhaust leak, some lean poping from it.little bit of a rough idle, but I hope it clears up once the exhaust leak is fixed. was getting a code for the cat not working probably because of the leak.
I will try to fix it tomorrow, just going to pull off that part of the exhaust and weld whatever crack I find
I finished replacing all the plugs and wires. half the plugs were changed and the "hard" ones were probably still the stock ones... so I replaced them all... and new stock wires.
I found the exhaust leak, its right above the cat converter after the manifold. weird places to get a crack, anyone seen that before on ls1s?
the door doesn't have any stickers on it so I couldn't check any codes.
the SS runs pretty good now other than the exhaust leak, some lean poping from it.little bit of a rough idle, but I hope it clears up once the exhaust leak is fixed. was getting a code for the cat not working probably because of the leak.
I will try to fix it tomorrow, just going to pull off that part of the exhaust and weld whatever crack I find
also as previously mentioned the leak before the cat will let fresh air into the exhaust causing the LTFT's to eventually go off which will effect WOT fueling to a point and performance will suffer. I'd fix the leak and replace that o2 and see where youre at
#36
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I must have missed that in his later posts didnt see it in the op both m6 cars wil be the same as long as there hasnt been a gear swap as rpm said. ![Mr. Cool](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_cool.gif)
Where did you look? Every SS car got one whether or not it had any additional options the rpo codes from gm should be on the drivers door and the slp one should eb in the same place on the pass side.
also as previously mentioned the leak before the cat will let fresh air into the exhaust causing the LTFT's to eventually go off which will effect WOT fueling to a point and performance will suffer. I'd fix the leak and replace that o2 and see where youre at
![Mr. Cool](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_cool.gif)
Where did you look? Every SS car got one whether or not it had any additional options the rpo codes from gm should be on the drivers door and the slp one should eb in the same place on the pass side.
also as previously mentioned the leak before the cat will let fresh air into the exhaust causing the LTFT's to eventually go off which will effect WOT fueling to a point and performance will suffer. I'd fix the leak and replace that o2 and see where youre at
#37
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thats odd has the car ever been painted or in an accident? someone removed them. no matter you can call SLP give them the vin and they will confirm all the options on the car its build date etc. are you sure its a real ss? not that it matters in terms of performance though
#38
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99 egr mod scroll down to photo#6 to see what im talking about. http://www.installuniversity.com/ls1...r/ls1-egr.html
#39
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well one of the bolts from the cat to manifold broke off flush with the flange.... i welded up the big crack around the flange on the cat side... would be done if it wasnt for the damn broken bolt...
not sure if i will need to take off the manifold or maybe use an easy out on the broken bolt... well see... its becoming quite the pita
not sure if i will need to take off the manifold or maybe use an easy out on the broken bolt... well see... its becoming quite the pita