So If your car is tuned on certain PSI. But you want it to run lower. so youturn the boost down with mbc.

Will this cause knock?
it is doing it on mine. tuned on 38psi but running 33 and it is knocking.
Will this make your car run rich? and cause knock?
E85 BTW
thanks

 

It depends how the car was tuned and aggressive the tune is what are your arf's now??and how much peak timing??

 

AFR at full boost is around 11.7 to 12.3
22 for peak timing

Also making Tah Tah Tah noise from the exhaust around 5k-6k.

 

and your getting knock with the boost turned down ????how much boost did you turn down too??also who tuned the car??

 

turned down to 33.
knocks on 34 and the Tah Tah Tah sound from the exhaust.

 

Tah tah sound?

Should knock on lower boost. Only thing I can think of is the new load cells you're hitting. They may have too much timing.

 

I thought e85 cant have knock?

 

sounds right to me evoryder! ..E 85 is a very different then a pump gas or meth..

 

Should knock on lower boost?

so i should ignore the sound and raise the boost?

 

Heres an idea when you get your car tuned leave it the same after the tune. Why does everyon elike to change **** after they get a tune. No offense but you sound like my friend, he had gsx tuned at 29psi then decideds hes burning to much gas as he has to go wot every 2 min so he turns down the boost to 15psi, then turns down the fpr as he thinks his car is running rich then turns the boost back up to 20psi and turns his fpr up to more than it was when he was at 29psi. End story his car blew up as once you go changing **** its not tuned anymore!

 

sorry
i was just switching map from 93 to e85
in the process of raising boost, this happened.
i just stopped at 33 instead of going back up to 38, because of the sound.
thanks

 

3geclipse is right, the only way I would have two boosts set up is if I was running two different maps for two different fuel. I really don't get the changing boost to safe gas, is all in the tune. I still get very good mpg in my 500hp+ capable car running 1000cc and round 27psi. And if you are running different fuel type then I would run an ebc like the aem, for accurate change in psi when you change maps.

edit: changing 93-> e85 know it make sense, + e85 to 93 oct definetly need two different tunes.

 

Ok.
since i am on MBC with 2 maps with 2different fuel, solution would be for me to get EBC.
got it. thanks

 

in my opinion yes, for accurate boost. Just make sure that the ebc you run can be switched to two different boost settings, the aem does. you cans set . such as A:38 B:33 and you can switch boost whenever.

 

Thats what I would do. And get a fresh tune.