ok i'm looking to get an slp cat back with a bbk x pipe. does anyone know if bbk makes a shorty header for the mach? i would like to do the lt however i need to put the stock h pipe back in for emissions reasons as it's done every year in my state. any input would help. thanks.

 

Shorty's are junk, don't waste your time unless you have long tubes...

 

if your gonna go thru the whole process i would do long tubes.

are 4v's love breath and shorty's are a waste ot time

 

But only do LT's if your not worried about emissions...that's what I've been told.

 

does anyone actually have dyno numbers, short tube versus long tube. since i've joined this site everyone says gets long tubes but i'm curious to know how many people actually know how much of a benifit it is.

 

I wonder too. I only have experience with longtubes on LS1s, in which I had significant gains (with a dyno tune included). No idea what shorties give you, but I do know that there will be a gain, no matter how slight it may be. Anything is better than the stock manifold. I feel like you should gain at least a solid 10rwhp with just shorties.

LudiChris, do some searching on that BBK x-pipe before you buy. I have heard alot of people (and read quite a few posts) complaining about the BBK-X. They all say it has a bad vibration or rattling sound at certain RPM. Those SLPs are going to magnify that sound immensly.They sayBBK doesn't have the correct flow that an X-Pipe should have due to the design. Supposodly, it's more of a chambered design. I only read/heard this and don't have any personal experience with them, but thought I would pass it on.

 

i have a bbk x pipe and yes i do get a rattle around 12-1500 rpm. no one makes shorties for the machs only the gts. if you have emissions just get longtubes and a catted x pipe with lm1s they sound amazing that way. and i also heard if oyu go with bbk mid pipe you have to go with a bbk headers and same for mac and the rest bc they wont fit right. im installing some macs on my mach this winter and dyno tune. my tuner said with fullbolt on machs he sees around 305-310 rwhp. so they do love to breat but they need some headwork cams and a major tune and you will be set.

 

http://www.kennebell.net/techinfo/fo...raTechTips.pdf some might find this interesting reading some may not.

 

Thanks for posting that link.

 

MM&FF did an article like last year on this I'd have to dig up the mag and check it out but the only difference between shorties and the stock mani's was 1-3 hp depending on mods. Definatly not worht the time...