[lowrider]

I know of no after market mid pipe made for the ISF. The exhaust systems available are either Cat (Manifold, Header) back or Axle back. To get rid of the secondary cats, some folks have welded in straight pipe in their place. Any competent exhaust (muffler) shop can do this. IMHO, there is a severe restriction in the stock axle back rear "Y" section. There are two available headers for the ISF - Sikky and PPE. Again, IMHO, the workmanship is superior in the PPE unit. However, from the results I have seen, mine included, both headers seem to produce similar results.

My system consists of PPE headers, Hi Flow cats, a custom fabricated full dual exhaust system with an "X" pipe, glass pack resonators and modified stock mufflers. I also have an o2 conditioner to keep the CEL at bay.

Lou

 

[lowrider]

Lowrider-

Roughly how much bhp you think with the PPE headers and hi flow cats the F makes? I gained 28 HP before and after PPE headers (with Hi flow Cats)I understand temperatures and humidity and other things effect this, but i would just like an estimate. I'm getting the PPE headers and cats soon and i would just like to know how much power i should get. Also is this a noticeable gain? This gain is very noticeable because it comes thruout the RPM range.Also how loud is the Joe Z exhaust with these mods? The JoeZ exhaust has great workmanship IMO, but it's just too loud for me, some have said the Borla system is quieter. I have not heard the borla, but have heard the JoeZ.,I plan on getting the Joe Z exhaust later but I don't want something obnoxiously loud. What is your opinion on the Joe Z exhaust with these mods? Are you glad you chose it over the other aftermarket exhausts available for the F? I do not have the JoeZ exhaust, I have a custom dual system with HiFlow cats, an X Pipe, Glasspack resonators, and modified stock mufflers.

If i were to go to a muffler shop and get straight pipes made and welded in would there be a check engine light? There will be a CEL after the header install unless you use the o2 conditioner supplied by PPE. Getting straight pipes welded in, in place of the secondary cats will have no affect on the electronics and will not produce a CEL.

thank you

I have added my answers to your post above in Red.

Lou