2012 l99 camaro and cx racing 76mm 1.15 a/r problems
04-06-2015, 08:55 PM
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2012 l99 camaro and cx racing 76mm 1.15 a/r problems Hi i recently built a turbo kit for my 2012 SS Camaro convertible and i am having a problem with the boost ,, the boost spikes to 9psi then drops to 7.2 with no reference line even hooked up ! basically gates are not even opening ,5psi springs 35mm x 2 tials running back into 2 1/2 inch exhaust not the down pipe .. Turbo is a CX Racing 76mm with a 1.15 a/r and a 77mm ex. wheel t4 divided,,2 1/2 crossover 3 inch up-pipe to a t4 flange (wastegates are before the up-pipe ) , 3 inch intake from turbo to air to water intercooler 3 inch out stepped to 4 inch to the throttle body , 4 1/2' tall x 3' inch wide down-pipe (oval) , split two outlet to 2 1/2 duals exhaust stock manis, stock engine , 515 hrspower 550 torque to the wheels on 9psi dropping to 7.2 psi ,no cats , has knock with 9 psi "spike" with 11' timing and 11.2-3 afr ,tr6's , cant figure it out , any ideas would be appreciated
04-06-2015, 09:59 PM
#4
Nice car. I have had my 2012 turboed since it had 12000 miles on it. I built the kit myself too. Im moving up to an s480 here pretty quick. I went opposite of you and put it on the drivers side.
anyway as for your issue. most likely the waste gates are opening. the back pressure from spinning the turbo is pushing them open. since you only have a 5 pound spring in them its very likely your turbine is small enough its causing the waste gate to open even though you don't have the reference line hooked up. you may have to run a much stiffer spring to get the pressures you want out of the turbo. I only see one waste gate in the pictures can you get better pics of the waste gate placement and the merge between the manifolds.
on my last note be careful with that engine. mine lasted less the 24 hours after I got it tuned with the turbo the first time. the tuner said I have been tuning these forever. He went to aggressive with the timing and number 7 piston blew apart and exited the block. made for a really bad day. the tuner said he would pay for a new engine then he went out of business like a week later and disappeared. gotta love it. I don't know if its because of the cam or the dod reliefs on the pistons but they don't seem to like a lot of timing. The cam is a turd so id change that as soon as possible.
anyway as for your issue. most likely the waste gates are opening. the back pressure from spinning the turbo is pushing them open. since you only have a 5 pound spring in them its very likely your turbine is small enough its causing the waste gate to open even though you don't have the reference line hooked up. you may have to run a much stiffer spring to get the pressures you want out of the turbo. I only see one waste gate in the pictures can you get better pics of the waste gate placement and the merge between the manifolds.
on my last note be careful with that engine. mine lasted less the 24 hours after I got it tuned with the turbo the first time. the tuner said I have been tuning these forever. He went to aggressive with the timing and number 7 piston blew apart and exited the block. made for a really bad day. the tuner said he would pay for a new engine then he went out of business like a week later and disappeared. gotta love it. I don't know if its because of the cam or the dod reliefs on the pistons but they don't seem to like a lot of timing. The cam is a turd so id change that as soon as possible.
04-06-2015, 10:52 PM
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Nice car. I have had my 2012 turboed since it had 12000 miles on it. I built the kit myself too. Im moving up to an s480 here pretty quick. I went opposite of you and put it on the drivers side.
anyway as for your issue. most likely the waste gates are opening. the back pressure from spinning the turbo is pushing them open. since you only have a 5 pound spring in them its very likely your turbine is small enough its causing the waste gate to open even though you don't have the reference line hooked up. you may have to run a much stiffer spring to get the pressures you want out of the turbo. I only see one waste gate in the pictures can you get better pics of the waste gate placement and the merge between the manifolds.
on my last note be careful with that engine. mine lasted less the 24 hours after I got it tuned with the turbo the first time. the tuner said I have been tuning these forever. He went to aggressive with the timing and number 7 piston blew apart and exited the block. made for a really bad day. the tuner said he would pay for a new engine then he went out of business like a week later and disappeared. gotta love it. I don't know if its because of the cam or the dod reliefs on the pistons but they don't seem to like a lot of timing. The cam is a turd so id change that as soon as possible.
anyway as for your issue. most likely the waste gates are opening. the back pressure from spinning the turbo is pushing them open. since you only have a 5 pound spring in them its very likely your turbine is small enough its causing the waste gate to open even though you don't have the reference line hooked up. you may have to run a much stiffer spring to get the pressures you want out of the turbo. I only see one waste gate in the pictures can you get better pics of the waste gate placement and the merge between the manifolds.
on my last note be careful with that engine. mine lasted less the 24 hours after I got it tuned with the turbo the first time. the tuner said I have been tuning these forever. He went to aggressive with the timing and number 7 piston blew apart and exited the block. made for a really bad day. the tuner said he would pay for a new engine then he went out of business like a week later and disappeared. gotta love it. I don't know if its because of the cam or the dod reliefs on the pistons but they don't seem to like a lot of timing. The cam is a turd so id change that as soon as possible.
Thanks bud ! The gate that is pictured is not on there any more , the car is still at the dyno and they have been doing the work to it cause ive been in indiana and cant be there ,, im gonna pick up the car tomorrow and check it out , back pressure things like that ,, the tuner said he tried everything with the gates , put boost on top and such and it wont make more than 9psi and drops to 7.2 no matter what , i just think its wierd , ive built over 50 kits and never had this problem , and also ive seen lots of engines make 600 plus to the wheels with stock cam ? but i agree i would be alot easier if i changed it ,,thanks for the input i really appreciate it
04-07-2015, 12:00 AM
#6
I have seen many engines make 650 also with the stock cam but this one having DOD and vvt makes it much harder. Plus the DOD lifter suck reliability wise. Take it from a gm tech. as for the boost, exhaust or boost is escaping somewhere. Likely one of the gates but I who knows. Let us know what you find. Good luck.
04-07-2015, 08:14 AM
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I have seen many engines make 650 also with the stock cam but this one having DOD and vvt makes it much harder. Plus the DOD lifter suck reliability wise. Take it from a gm tech. as for the boost, exhaust or boost is escaping somewhere. Likely one of the gates but I who knows. Let us know what you find. Good luck.