I did something really dumb the other night while installing my new header. I had stufed some shop towels (blue scott ones) into the downpipe while I sprayed high-temp paint/cleaned up gaskets and mating surfaces/other prep. I then installed everything, forgetting to remove the shop towels. On the test drive, power felt down, and I suddenly realized what I had done.

Last night I removed the header to inspect for damage, evertyhing looked fine, but no sign of the towels. Compression test was perfect, and it idles perfectly. But top-range power is noticeably reduced. Instead of my boost decreasing as expected, it increased from about 6.5 to 7.5 psi. AFRs also went from the low 12's to the mid 11's. I suspect the towels are clogging the muffler. Anyone know of a way to fix this easily, or am I looking at a new muffler here?


Modified by borat at 12:41 PM 2/29/2008

 

Is it a straight-thru muffler? Your best bet would probably be to try one of those plumbing pipe snakes to try and get the towels out.

 

My cousin, he has very funny mental......sorry. Borat's kinda funny.

That's a good screw up. Towels in the exhaust. . I'm with inspyral. Try to snake it out, or drop the exhaust and see if you can pull them out. I think they melted/burned/whatever the hell happens to shop towels after being stuffed in an exhaust, so you just might be lookin at a new system.

 

Thanks for the replies. I did snake out the exhaust yesterday: clean as a whistle, nothing in there. I also did a quick drive with no muffler since it's the stock one and you can't really snake that, and the problem was still there. I then switched back to the stock manifold / downpipe, and things returned to normal. Looks like the kamikaze header isn't the great supercharger performer everyone thought it was.

I know I need to retune the AFR, but the fact that the boost went up by 1.5 PSI pretty much across the board tells me that this header is restricting things. Maybe I need a full catback to let them breathe correctly...?

 

I know with forced induction, the better the exhaust works, the better the blower/turbo works. Hell, I'd put a DC 4-2-1 header on it and a 2 1/2 or 3 inch exhaust on. But thats me. Maybe a good re-tune might work for you as well.

 

Well that's why I was putting the header on in the first place. Jackson Racing says this:

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JR &raquo;</TD></TR><TR><TD CLASS="quote">Keep in mind, in a supercharged engine, as the air gets through the engine better, the boost will actually go DOWN, but the power will go UP! So, don’t be surprised if you start improving the intake air and exhaust system and your boost actually starts reading slightly lower than it did when it was all stock. Conversely, if your catalytic
converter is starting to deteriorate, you will see higher boost than normal, but your engine will perform poorly.</TD></TR></TABLE>

So since my boost went up, it means the new header was doing more harm than good. And I know it wasn't my cat, because it's not even there anymore. Guess a 2.5" catback is in order.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by King V &raquo;</TD></TR><TR><TD CLASS="quote">I know with forced induction, the better the exhaust works, the better the blower/turbo works. </TD></TR></TABLE>

that is true most subie guys see a lot of gains from turbo manifold, downpipe, exhaust but its actually cause boost is rising...