Okay as you can tell by my post count I am a noob. I am trying to learn and have been reading lurking for some time.

My question is this:
I currently have a dyno tune. On a completely stock motor, only mod being a MBC boosting at 24psi. With Exhuast flow being better when I add a HFC and a CB exhaust. But still keep the Intake unchanged will I throw my AFR's out of whack. I know or understand that I will probably spool and build more boost, so for that I just have to turn down the MBC.

From there would I just watch my knock sums and AFR to ensure that I am safe? or am I having to do a whole new tune.

Thanks.

 

i would get my car retuned with out the MBC esp if you dd your car up in canada where you have warm summers and freezing cold winters. Thats just my opinion. If you have a boost spike, the MBC will do nothing to lower the boost. If you have either the stock boost control system or a 3-port, your car will be ALOT safer.

But if your tuner doesnt know how to tune ecu controlled boost, then watch your boost and your AFR esp with the weather getting cooler. Your boost might spike with the weather getting colder.

 

Thanks for the concern of the MBC. Ball and spring MBC's have very little variance in boost change. Really in spiking terms not much different than stock. If I had a bleed style MBC I would be more concerned but modern day high quality MBC's like grim speed, forge, perrin ect are quite safe. Boost curve is very smooth. Thats also the sweet thing of having a boost gauge and evoscan I can adjust on the fly.

Back to the topic of exhaust flow and change in AFR's