I recently had to switch up my exhaust because the baffling inside my muffler came loose and it was rattling. My old muffler was the old school 5zigen that looks like a greddy evo2. The new one is an apexi N1.

So...My problem. As soon as I installed the new exhaust my boost was topping out at 20psi. At this boost level my ignition was breaking up. The car used to top out at a healthy 15psi. I asumed that the increse in boost was due to the N1 canister being far lest restrictive, therefore creating less backpressure in the exhaust system. So I bought a silencer for the exhaust to restrict the flow again. It worked. But I hate the sound of the exhaust with the silencer.

Is there a way to take out the silencer but still hold the boost at 15psi?

 

I hope you have a boost controller or something. If you are running 15 on you map and its spiking to 20 you will have big problems

 

No, I fixed it with the silencer in the exhaust. And I'm not on a stock map. Pfc tuned for 15 psi w/ 1600cc secondarys. I'm just wondering if there is any way to stay at 15psi without restricting my exhaust flow. And it only went to 20psi once or twice. I was watching my A/F and injector duty it stayed pretty melow

 

20 psi, on the stock turbos?. jesus man.. u need to get that under controll

 

No, not stock turbos. Sorry should have given some info on my car.

Mild street ported reman 13B
Apexi Rx-6 single turbo kit
Pfc tuned
Wasegate spring @ 15psi

 

well just get a softer wastegate spring, like a 10 psi or so and just get a boost controller to adjust from there. manual or electronic wich eva fits your wallet.

 

ok, Sounds like a plan.Boost controllers can only increse boost from the wastegate spring right? You cant use a boost controller to set the boost lower than the spring is set at?

 

Correct, spring determines lowest boost setting, boost controller can only raise it.