so i took a trip to synapse motorsport today and dynoed 396 whp and 389 wtq. i recently got tuned by trifecta running 25psi and 15.5* of timing. i also fixed a boost leak in the chargpipe and didnt get retuned... i was at a 12.1 afr now on the dyno the sniffer AND my interceoters are reading in the 13s wot until like 5500 then dropping to the mid 12s, we did 1 high boost pull and 1 low boost pull with the traction control button. i did not want to damage the engine and took there advice and stopped. also i was getting boost cut. during mid pull car just wouldnt dropped all boost this is maybe clutch slip? is the boost cut cluch slip? does getting tuned with a boost leak cause a lean condition after fixing?

 

https://www.cobaltss.net/forums/memb...20/dyno-15228/ 263whp is on 15psi with select A tune off for a baseline. the car is on stock clutch still waiting for lift to install stage 4 clutch.

 

Everyone is so obsessed with the boost. Its the knock that kills the motors. Boost can cause knock but also other factors including iat2s spark curve multiple pulls trims being off badlys. I would not tune the car until it is functioning properly.

 

Right, however LNFs can get away with being a bit more lean than an LSJ due to DI. Of course its bad on the motor if you are too lean, but richening it up may be a better idea.

 

12.8-13.0 is about the sweet spot with these cars on HPT and 93. But trifecta is usually mid to low 12s so I believe I would start data logging with a couple short pulls. You're probably too lean for the timing Vince runs. His way is richer but more timing.

 

HP tuners man, that's all I have to say. BTW what gas were you using?
Post your graph so we can see it.

Here is mine on e47.

 

93 octane there's a link in the second post. I know I'm not commanded this lean I'm commanded 12.1 afr. Would a boost leak cause my afr to go lean? I'm afraid to log this car I don't want to melt pistons at 13.2 afr in the mid range. The only thing I did was fix a boost leak...

 

I'm pretty sure a leak would probably make you run rich. AFAIK Vince likes to make his tunes rich for some reason its not the case. Maybe the dyno readings weren't calibrated correctly. Honestly the best thing to do is get logs. I still recommend changing to Hptuners.

 

I'm thinking the boost leak made it look rich and now with them fixed and no tune update its running lean... The sniffer and the aeroforce gauge in the car are showing 13.2 afrs until 5500rpm the it drops into the 12s. I don't have a tuner nearby or the hp cable. Also I already payed Vince and like the select a tune.