Timmy_Jones

What is the power difference between a Longtube header setup (with full exhaust behind it) and the stock manifolds with X pipe and a catback? (this discussion for just 99-04 NA, V8, 5 speed mustangs)

Car will only ever see bolt-ons. I was thinking just an xpipe and borla back, instead of longtubes and everything else. What is the power difference? Say with an intake and tune. Price difference is certainly there...is the power that much different? How restrictive are the stock exhaust manifolds?

Either setup would be with hi-flow cats and a straight through borla/loudmouth catback setup.

MU71L4710N

you will gain less than 10hp, and if your paying a shop to do the labor, you will have anywhere from 1000$-1500$ or more (depending on how much you buy the headers for and how much the shop wants, most places charge 500 or more) invested for honestly, not much gain.

once you have some cam work, nitrous, or a blower, the gains are much much higher (20+ hp). stock manifolds flow well enough for an NA bolton 2v though. the higher the HP your motor makes, the more gain you will get from getting longtubes.


results of my google searching during work yesterday which i found interesting.

http://www.mustang50magazine.com/tec...est/index.html

keep in mind these are mac shorty headers they compare it to, which are far better than stockers. i wish they would have done a test with the stock mani's too. but basically they said until your motor is putting out 350+ hp (which a bolton gt will be about 300), the longtubes don't really work as efficiently as they are designed to. both add HP over stock, but you may or may not justify the price of headers and an install to only gain a few ponies.

Timmy_Jones

Thank you! I keep comparing these to my LS1, but it seems some info does carry over. I know on the 00-02 ls1 engines the stock manifolds are fine for bolt ons, but the Y pipe is restrictive.

Sounds like intake, tuner, gears, xpipe and catback is a solid setup. Thank you for the info, header installs are ALWAYS a nightmare.

DreamerGT

Im not sure how much power I gained, but when I went from just welded in flowmaster 40's to longtubes and o/r x. The car pulled like night and day. Put a huge smile on my face.

Timmy_Jones

Has anyone ever made the switch from a catback/xpipe setup to a longtube setup and felt there was a significant difference? No doubt that stock -> longtubes was a huge difference!

Anyone have 1/4 times with basic mods and an xpipe vs. headers?