My system consists of 3 inch downpipes which I would like to keep the same diameter all the way out. I was planning on just running dumps behind the front tire or dumping in front of the rear tires. But started wondering if there were any benefits of using H- or X-pipes on a twin turbo setup?

I understand there would be a fitment problem of trying to connect a 3 inch pipe under the car....

Anyone?

 

Well, i've never tried running without the midpipe, but i do know that switching from H to X pipes that i picked up a lot. My best with the H pipe was 12.11@123 mph, then i switched to the UPR X and went 11.77@126, the only other thing i changed were the sprark plugs. The plugs were good on the 12.11 run, but i decided to give NGK a try after running autolites. Those were the only things i changed.

Could you run a stock style H/X pipe for shorties or longtubes? Pypes Ehaust makes midpipes cheap. I know for a 2.5 inch X for longtubes its $59.

 

there is no need for the crossover, so if you want, just run them straight out the backwith bullets or something like that. i have ultra-flows on my car with an HP kit and H/C/I and its dead quiet

 

yes, i had the ultra flow catback as well. Ultraflows are your friend

 

What was your 60' on each run, and what was the temp like outside. You can't go by what you picked up time wise. Hell, I ran an 11.84@117. The mph is the HP factor, ET improvement is a driver factor. So basically you're saying you picked up 3mph by switching. That could be a change from summer to fall.

 

I was told a member on this site picked up .25 to .30 by doing away with the h-pipe setup on his twin setup and going 2 individual pipes.This has been brought up before.

 

the 12.11 run, my 60' was 2.08 and the temp was in the low 60's (december) and the 11.77 run my 60' was 1.99 and the temp was in the mid 70's. Thats why i was surprised when i saw the 3 mph increase, it was in warmer weather and the only things changed was the spark plugs and the switch from H to X pipes.

 

Racer99-
I had done some searching and couldnt find a definitive yes or no that it would help or hurt.

But thanks all for the advice. I'll just stick with my original plan of dumps. I too was planning on running ultraflows - the 6" round (3" in 3" out").

I was also afraid it was going to be extremely loud but if you say its quiet....

 

the ones you are talking about are the Dynomax Bullets, the ultraflows look just like a normal oval muffler but they are straight through. I dont know how they did it, but straight through and its quiet??? Works reall well!

 

The ultraflows come in a 6" round version as well, the bullets are only 4" round in the smaller sizes (3" and under)