TC 78 Limits?
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I have been running a turbo set up on the street for a couple of years at around 11# of boost. (no track around here) I decided this year to up the boost, I replaced the tc 76 with the new tc 78. Put some slicks on & found some secluded roads.
Well I could not get to 15#'s so I replaced the MBC with one that I know is good. I finally got to about 16 on my guage but I have yet to hit 210 KPA on HP Tuners? It hits 205 which doesn't jive with my guage right? It makes some nice power but I am wanting more. LOL
My question is can I be out of turbo? I have a 347 with afr heads, a nice free flowing kit with open down pipe. Here is another piece of the puzzle, I am at around 3500 to 4000 feet in elevation.
All my pipes are nice & tight, I don't think I have any leaks.
Well I could not get to 15#'s so I replaced the MBC with one that I know is good. I finally got to about 16 on my guage but I have yet to hit 210 KPA on HP Tuners? It hits 205 which doesn't jive with my guage right? It makes some nice power but I am wanting more. LOL
My question is can I be out of turbo? I have a 347 with afr heads, a nice free flowing kit with open down pipe. Here is another piece of the puzzle, I am at around 3500 to 4000 feet in elevation.
All my pipes are nice & tight, I don't think I have any leaks.
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I just did some runs tonight & really it stayed mostly around 195 KPA no matter how much I turned the MBC up. It also ran my injectors up to 80 to 83 % DC at 11.0 to 1 afr spraying meth. So I am probably pretty close to max on my fuel.
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Yes I have read everything about this turbo on this site. I'm just trying to figure my boost #'s.
I just did some runs tonight & really it stayed mostly around 195 KPA no matter how much I turned the MBC up. It also ran my injectors up to 80 to 83 % DC at 11.0 to 1 afr spraying meth. So I am probably pretty close to max on my fuel.
I just did some runs tonight & really it stayed mostly around 195 KPA no matter how much I turned the MBC up. It also ran my injectors up to 80 to 83 % DC at 11.0 to 1 afr spraying meth. So I am probably pretty close to max on my fuel.
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Boost controllers are limited by what the wastegate can or can't do. Wanna see the real limit of the turbo? Install a block-off plate before the wastegate and be prepared to replace head gaskets at minimum. I believe that turbo can make 20+ psi on your motor.
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I bought the WG from you guys, I think it was a 38mm Ultra? If I remember correctly. What can I get that will bolt in it's place? I don't have a lot of room for one that is physically much larger
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You don't need a bigger gate...just more spring tension. Have you stacked the springs that came with the gate. The Ultra's came with extra springs to stack up the tension on the valve.
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so would a tc76 be able to make more power on a 5.3 or a smaller motor because of backpressure?
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