Is a MAS/filter a must w/ catback

[firstbite]

Hey guy's I have watched this board for a while and it is awesome, This is my first post. I've got a '99 electric grn Cobra bone stock and am thinking about putting a BORLA exhaust on, do I need to make any other mods(like changes to MAS), or can I slap it on for a quick 10-15HP. My snake is post fix, I think they leaned it out by reflashing the chip, does that have any impact? Also once it is time for headers do you have to keep the same brand as the catback? Your help is greatly appreciated!!!!

 

[REDLYNE]

a local guy!

Firstbite-
Glad to see another Chicago-land member on the boards. I live North of you right by O'hare.

Anyway, to answer your questions:

Don't expect too much out of a cat-back. They mostly just help with exhaust sound. A good cat-back with bigger pipes and straight-through mufflers (or no mufflers for that matter)...would only be good for only a couple rwhp. I have yet to do a DYNO, but I have heard that a good cat-back (Borla, Bassani, Maganflow, etc.) will amount to a 2 or 3 rwhp.

The best and easiest place to get rwhp HP out of an exhaust is the intermediate pipe. This is where the catalytic converters are. The 99 Cobra comes stock with an H-pipe that has FOUR catalytic converters. This is very inefficient. Some people have chose to remove the cats completely, however since this is illegal as far as emissions are concerned...sometimes (depending on what you are doing with the car) getting a pipe with high-flow cats is your best option.

As far as the Mass Air-Flow Sensor goes, you do not HAVE to change this when you do exhaust changes. Think of it this way: if bigger, better exhaust helps the car "breath out"....then a MAF or
TB, or Cold-Air INduction is what helps it "breathe in". Your throttle response and gas mileage will improve with a MAF...your TQ and HP will improve if you switch your intermediate exhaust.

Keep in mind, that sometimes the HP and TQ you gain on the high-end....makes things dull out on the low-end.

Here's my advice for you: Seeing as how your car is stock right now, I assume you don't want to do anything to drastic. So, get an intermediate exhaust that has high-flow cats. THis will keep your car 100% street legal and will improve both the sound and the performance. X-pipes work the best with high-flow cats. H-pipes work the best with no cats.

If you still want the sound changed, then go with the cat-back. Borla is one of the more expensive ones (because of name recognition, reputation, etc.) but I wouldn't say they are hands down the best. Borla exhaust gives your car more of a "growl" but tends to drone a LOT on the expressway.

Sorry I was so wordy...

 

[isdnmatt]

What MAF would you recommend?

-Matt

 

[REDLYNE]

pro-m

go with either the pro-m 87mm or the pro-m 80mm. Both seem to have the same results, though some have reported better throttle response with the 87mm when used with an aftermarket (BBK) throttle body.

 

[firstbite]

Thanks Redlyne