I'm thinking the muffler and cat are one piece. That's not the o2 sensor your looking at is it? If yes, most people leave it unpluged. You should be able to hear the wstegate open under acceleration/boost. If in doubt, remove the boost line and apply a little air (what ever bar spring you are using) to open the valve up. You should hear the valve open and close.
New headers, turbo (k27-7200 or better) and muffler will help A LOT, but I would also get a larger intercooler to cool down any heat you have generated with the new turbo, especially if you go with 1 bar sping. You could easily get 325-340 rwhp.
Originally posted by e170drvr
Hey guys, got a couple maybe dumb questions. If you put an aftermarket exhaust on your 87 930, was thinking about the Fabspeed single outlet (for lack of any better ideas) it is my understanding that the cat is removed from the system. I noticed that there is a small metal line that runs from the cat to a sensor under the engine(not sure what it is) My question is, what do you do with this line if the cat is removed, or is it attached back to the muffler? Second, can you guys hear your wastgate opening? what indications do you get with a properly functioning unit (wondering if it might be stuck open)? And finally, I am planning on bolting on the muffler, k27, and considering headers with heat, but not looking forward to removing the exhaust studs on the exchangers, how much of an improvement would they make on an 87 with these mods. don't plan to track the car just want a little more kick in the pants, and maybe get the turbo spooling a little quicker.
Thank you for any help you can give me.