Bone stock 83 GS. Stock air box (or whatever that contraption over the exhaust ports is called) has a pretty nasty leak, engine bay gets hot, smells bad, etc.. doesn't overheat though.

Is there a header out there that if I get a cat delete pipe will work with the rest of the system to the stock muffler? What kind of power gain can I expect from this?

 

air cleaner, the thing on top of the carb is an air cleaner.

the RB header + presilencer bolts to the stock connecting pipe + muffler. or cat back if you prefer. 10-12hp gain. the stock muffler is ok, but it gets a little tinny/raspy.

 

is it really worth the cash to get the street one instead of the uncollected one, then collecting it elsewhere?

 

I don't recommend using the stock muffler with a header, even with a presilencer. It sounds loud and bad.
If you can do your own fab work with thick-walled pipe (I can't stress enough how important that part is) and make a proper merge collector, there's not much difference between the two. The main problem with the collected header is that it collects to 2" (the FB version does, anyway), which is too small to make any real power. But if you're using a stock muffler, that's a moot point.

 

just buy the kit and weld it up yourself. Very easy and cheap

 

I've no welding experience, only a little soldering...

I want something that gives me a little edge now for DD that won't need re-upgrading when this becomes a track car... without breaking the bank.

 

Im running a universal exhaust from RB and 2 1/2 in piping from header to muff. Doesnt sound loud at all.