Let's get this out of the way first. I know, why am I still beating my head against the sequential setup. https://www.nopistons.com/forums/pub...1047683358.gif Well, I am. I'm not a quitter (yet).



A few months back you folks helped me with some troubleshooting and a lot of improvements were made. I have since done another track day and noticed yet more stuff to deal with.



First, during highway cruising at 80, if I want to accelerate to get around someone, I drop into 4th and try and go. It seems as if the car just kinda barely accelerates. In lower gears, it goes like a bat outa hell. Coincidentally, I have one of those exhausts that has the silencer you can insert and remove. With it out (at the track), the cars seems to behave reasonably better. With it in, it really takes the top end away. Almost as if my exhaust flow is pretty marginal even without the silencer.



Question. Are these the kinds of symptoms that happen when your cats start to clog or you have an overly restrictive exhaust?



Second, is the 929 Master Cylinder swap a no-brainer? Does the stock resevoir fit the 929 MC? Do I get the ABS 929 MC if I have ABS?



Thanks in advance,



Jim Walton

Jim, I used to use silencers when I had the Apexi N1 dual cat back. The silencers will rob you of alot of horsepower. They completely block the air flow leaving the exhaust, seriously limiting the air that your engine is able to move, hence slowing your ass down. If you wanna go fast your car has to be loud. There is no way around that. Can't help you on the BMC sorry`.

what boost numbers are you hitting?

I knew someone was going to ask me what I was boosting...



I (still) don't have a boost gauge, which will make it pretty tough for you to diagnose I know. I didn't have to deal with the boost issues at the track day too long becuase I toasted the brakes (long, stupid story) and had to limp home. Needless to say, the money that was set aside for boost and afr gauges was blown on rotors and pads.



To refine my earlier question, if your exhaust is overly restrictive, in 4th or 5th at about 3500 rpm with the throttle close to wide open, will the turbo system just vent out the boost because it has nowhere to go? Or do I still have some issues with the vacuum and solenoid systems controlling this stuff?



Thanks again for the replies,



Jim