MrHorsepowerLSx

iTrader: (13)

You'll be around 350-360rwhp, do you have e fans, what's the exhaust setup consist of? My motor was close to your build but in a rcsb, so the numbers should be taken with a grain of salt. I picked up 52rwhp with E fans, exhaust swap and a tune up and my setup is maxed out

Ray Finkle

I do already have E-fans but currently has stock manifolds/cats with a simple cat back system. I mainly wanted to keep it as "legal" as possible since we have emissions testing in my county, but if 50+hp is potentially on the table, I may reconsider.

I don't have a problem throwing stock catted y-pipe back on once a year for emissions purposes.

A set of shorty headers would make life much easier for me, what are the gain/differences between long tube and shorty's?

MrHorsepowerLSx

iTrader: (13)

I run 1.75" LT's with a true dual 3" system dumped before the axle, prior to redoing my exhaust I had the same LT's 3" y-pipe with no cats and a single 3" system with a super 10 flowmaster and tailpipe, I also had the flex fan, after swapping some parts out I hit the dyno again and as my tune was I put down 391rwhp from the baseline tune of 349rwhp, then we pushed the injector envelope as much as we could and picked up 10hp more. So for what it's worth, you will have a heck of a time hitting your power number of the motor can't breathe, as far as shorties go, anything is better then the stock manifolds, but I prefer the low end power from the LT's not just "all around" power from shorties. I have emissions in my state as well, they do a visual inspection for the cat, my truck had gone through for the last 6 years

Ray Finkle

Alrighty, I said screw it, I'll deal with emissions testing when it comes next August. I ordered a set of speed engineering 1 7/8" long tube headers. Saw some pretty interesting dyno results showing 40+whp increases over stock stuff.

MrHorsepowerLSx

iTrader: (13)

I run there true dual 3" setup, I like it, the muffs aren't bad, I may change them down the road, but the low end power gain was worth it, I also picked up .3ths in 1/4 after swap

Ray Finkle

Nice pieces. Excited to get it running!