ICOOLUM Posted November 15, 2015 Report Share Posted November 15, 2015 Currently I am running the stock manifolds along with an off road H pipe into the stainless works exhaust. My question is will I gain by adding headers but changing out the off road H pipe with a hi flow catted H? I think my county is about ready to start checking for cats.I understand I will have to re-tune. Also is long or short tube the better option? Quote Link to comment Share on other sites More sharing options...
silly fast Posted November 15, 2015 Report Share Posted November 15, 2015 If they look for cats then they will look for headders. If they go in your GT500 then they are a pain to install. Headders aren't smog legel ether. Quote Link to comment Share on other sites More sharing options...
Robert M Posted November 15, 2015 Report Share Posted November 15, 2015 (edited) Currently I am running the stock manifolds along with an off road H pipe into the stainless works exhaust. My question is will I gain by adding headers but changing out the off road H pipe with a hi flow catted H? I think my county is about ready to start checking for cats.I understand I will have to re-tune. Also is long or short tube the better option? In my opinion, the safest way to "possibly" get through the initial "visual emissions inspection" is to have shorty's installed and when it comes to inspection time, throw the oem H back in place and the system will appear oem to the visual from the bottom side, which is where they look first. Getting through the visual inspection is the big deal, when they see "aftermarket" exhaust parts anywhere ahead of the catback when they initially look under the car, the flags go up and the bells and whistles go off, then they start sniffing around a little more. The problem is, FRPP no longer makes the shorty headers for the 2007-2014 GT500 and the JBA shorty that has been talked about on a few forums is not available yet. JBA says their shorty's will be CARB approved.........maybe that is why it is taking longer to get them to the market place. My FRPP shorty's are not CARB approved, and thankfully, for now I do not have emissions testing/inspection in my area. My thought is..............If you take off the oem rusty cast iron logs and replace them with a set of nice shorty's along with a nice large mandrel bent system (I have Shelby/JBA 3"), it will flow fine. Long tubes show better hp gains in tests that have been conducted in the past, but most owners who installed the shorty's were still running the choked down oem 2.5" exhaust that comes on the earlier cars. The 2011-up 2.75" is better, but still not mandrel bent, so it chokes in the bends around the axle. BTW - The outlet size on the oem cast iron logs is 2", so that is a flow issue immediately, without looking anywhere else. R Edited November 15, 2015 by Robert M Quote Link to comment Share on other sites More sharing options...
ICOOLUM Posted November 17, 2015 Author Report Share Posted November 17, 2015 Thanks guys, I appreciate the feedback Quote Link to comment Share on other sites More sharing options...
poppagroove Posted December 20, 2015 Report Share Posted December 20, 2015 I just installed the long tube headers on my 08 with 3" stainless off road X pipe running thru Borla axle backs.....sounds awesome!!!!! Quote Link to comment Share on other sites More sharing options...
ICOOLUM Posted December 24, 2015 Author Report Share Posted December 24, 2015 I've decided to go all Stainless works from long tubes, OR H pipe and retro straight through mufflers already installed. Adding upper and lower pulleys as well as steeda adjustable tensioner up top. Also added Keene Bell Boost a pump. Top it off with BMR front and rear sway's and Watts link. I already had all the rest of suspension repleced with BMR except went with Ford Racing springs. Cant wait to see the dyno results and feel the handling difference. As always thanks for your input. Quote Link to comment Share on other sites More sharing options...
Harry Posted December 26, 2015 Report Share Posted December 26, 2015 JBA has just released their shorty's to market. #1695s. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.