part throttle backfire at shift. Tuner advice
Alright guys, I'm having a bit of a problem with my tune. I've had a few setups running great, but this one really has me stumped. If I go near 3500 and shift, I get a pop through the exhaust.. it's not extremely loud. I've went from lean to rich in the whole vacuum portion and it still happens. the timing is conservative.
I've checked for exhaust and intake leaks all over.. not sure what is going on. any suggestions would be greatly appreciated.
the setup is as follows:
B16A w/ 9:1 c/r
Holset HX35
2.5" open down pipe
stock map sensor
450cc injectors
tuned on CROME PRO
fuel maps:

I know it's a fueling issue because if I shift fast or give it a tiny bit of throttle between shifts it doesn't happen.. but how rich can you get in vacuum and still have issues.. especially when you're cruising at high 13's AFR
I'm thinking the injectors might be at fault.
I've checked for exhaust and intake leaks all over.. not sure what is going on. any suggestions would be greatly appreciated.
the setup is as follows:
B16A w/ 9:1 c/r
Holset HX35
2.5" open down pipe
stock map sensor
450cc injectors
tuned on CROME PRO
fuel maps:

I know it's a fueling issue because if I shift fast or give it a tiny bit of throttle between shifts it doesn't happen.. but how rich can you get in vacuum and still have issues.. especially when you're cruising at high 13's AFR
I'm thinking the injectors might be at fault.
Do that to make sure the ecu doesnt think the throttle is still open when you let off. If its ok lean it out in high vacuum and give it more timing. That worked for me. Also see if you can get it in the mid 14s when cruising.
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