I have an '88 GXL, with a stock exhaust. I would like to upgrade it, however being a 4th year Mech. Engineering student has left me with very little funds to accomplish this. Therefore, I am planning on doing it in stages, header and presilencer in one stage, and a catback in the other.

My question is, which should I do first? I would likely go with the RB street header and presilencer combo, and either an APEXi or custom catback. Would running the header/presilencer combo with the stock exhaust to the back be better than running the stock manifold/precats/main cat and the upgraded catback?

Thanks,
Kyle

 

Most power gains are had by removing the stock manifold and cats. But they come at a cost. A header and presilencer will be significantly louder than stock, even if you use the stock catback system. There are small gains from replacing the catback, but not as much as freeing up the front half of the system.

 

there are a couple ways to look at this.
But My opinion is that If you get rid if the 25 pound cast exhaust manifold then you are achieving something.
you can start with that,then move to replacing the Stock Cans.

 

Any idea how loud a header/presilencer with the stock catback would be? I don't mind a loud car, as long as it is tolerable.

 

It wont be super loud.It will be tolerable but when you get on it the stock cans are like Bees.
Idle and low rpms are good though,and not a Cop Magnet.

 

Thanks, I am thinking I might just keep my eyes open for a complete used set-up, however if I can't find one I will likely go the header/presilencer first and then worry about the catback.

 

having just installed rb headers and bonez superflo cat today, i have to say with the stock cat back you might pull some unwanted attention...

 

I would start at the front and work backwards. Likely to see better gains going upgrading the front parts first. Then have a custom cat back built, using high quality mufflers with stainless steel packing. The fiberglass and cheaper packing material will burnout quicker with the high exhaust temps of these cars, especially if your turbo.

 

I will also be doing the exhaust from the front backwards. Header first, presilencer and cat next, then muffler last. Needs to be all quality equiptment, as mentioned already.

 

catback first, you dont want to add restriction as the exhaust flows. work your way forward

 

^ supahflyblt. You will be happier working your way forward...adding free flowing into restricting pipes doesn't help much. Your gains and losses will even out