Open Headers over TD's?
 

I currently have a true dual set up. I'm wondering if running open headers would actually slow me down or speed me up? I've been considering running open headers at the track to see how it does. Anyone know what would happen? Could I just put my bullets on the end of headers and run it like that all the time?

TIA.

Open headers would not be a good thing

I doubt you will do anything but loose alot of lowend and may pick up a hair on the top end... but thats with some decent extensions.

pretty pointless imo.

Alright, thanks guys.

I have dyno comparisons between open headers and 3" duals on my 383. it picked up about 25rwtq down low and 10-15hp up top. you should see a gain at the track. it is MUCH louder than duals though.

that's odd...i would think that the scavanging of an x-pipe would show a greater gain

Usually the scavenging will show a healthy gain in low end torque, primarily at low RPM. For High RPM horsepower production, its hard to outflow open headers. Many people and books, ls1 specific and otherwise, have stated at the track, go open headers for the best gain as well as weight reduction.

-T

here you go

https://ls1tech.com/forums/dynamometer-results-comparisons/144332-open-headers-vs-true-duals-383-a.html

like said above, open headers will give you a gain up high. for track purposes i say run them open.

however i would definately run some sort of extension off the header. the o2 sensors should be at least 16-18" away from the opening to avoid outside air from coming in contact with the sensor and causing you to run extremely rich

I still don't get it. Everytime this comes up people talk about how much low end you will lose. The guy has a 3600 stall and 3.73's. How long would he actually be in that "low rpm" range? Maybe idleing up to the starting line but that's about it.

I don't mean to flame but am I completely wrong on this? How high up does this low rpm range go?

My car has always run it's quickest with open headers (16" extensions off the collectors). I do have kind of a shitty x-pipe though. My 1/8 mile times are usually the same and my 1/8 MPH is actually better with the duals but, the car lays down at the top of the track in 3rd with the duals. I think my best pass with them is an 11.3 at 124.

anyone who says anything about "low end power" at the track is obviously ignorant of running at the strip, and should be ignored.

why the hell would you care? even if you're 100% stock, you still dont hit any "low end" area.

anyhoo, Tally TransAm had the right idea.. the reverb from the exhaust pulses will pull in outside air to your O2s.... this will mess with yoru trims and such at or near idle... once you're above about 2k, it has no effect, but if you're looking for consistant times, run a short extention... something like 6-8" is fine.

open headers to me just sound bad except on certain cars....i keep my duals on at the track and on the street

At part throttle they do sound like shit. At WOT on the bottle it sounds crazy. I've had a few people at the track ask me if I did a big block conversion.

I have two bulletsd on the end of my headers and its a daily driver. Nothing like starting you car in a parking garage and setting off EVERY alarm. And it is THE BEST flowing exhaust possible. With 4.10's and a 4600 8" stall i'm not worried about my low end torque.