track day with 99 Cobra. open headers?

[daveshapellSVT]

I went down to the track last weekend and i'm thirsty for more practice.. i'm gonna end up going next saturday cause i ordered some drag radials and they should be comming early this comming week.. Now i was wondering, would it be stupid to run open headers? I have stock headers, but i would think that would still give some power.. Stupid or is it worth a faster time? If i would get some gains how big?

Also, will doing this harm the car?

[GTStang]

A lot of tracks don't allow open headers. Plus I don't think your gonna find much of any power gain with it.

[SikNingStang]

yea, also I've been told when I was running open headers for a day before I had my exhaust done that I was risking burning up a valve b/c my exhaust wasn't long enough. If that's true then you'd be risking that too. Also you mainly working on launches and quicker 60' times aren't you? If so open headers will kill your acceleration.

[daveshapellSVT]

this is hardly comparable, but my buddy was running 15.01 in his GSR, then ran a 14.56 running open header.. So i figured if a tiny 1.8 liter bumbble B18 can manage a half second faster time then imagine what a mustang Cobra could do..

[BadA$$Snake]

Hmm, I don't really think that open headers would matter all that much. you might gain maybe a tenth of a second or so, maybe three at most. But my one question is this, what about back pressure, woudl you still make enough without teh full exhaust system?

[daveshapellSVT]

Think about serious horsepower making cars like top fuelers or even cars at the local track.. they don't run exhaust systems.. it's all open headers.. i never understood that whole backpressure deal..

[daveshapellSVT]

also think about how much power is gained by freeing up your exhaust with X pipes, headers and cat backs.. mach1's make 20WHP with a freer flowing X pipe.. i would think if you just eliminated the exhaust all together that would give the biggest results..

[z28 boy]

TO much back pressure is bad not enough back pressure is equaly as bad.

[daveshapellSVT]

why is it bad?

[z28 boy]

This is the simplest way i can explain it some body jump in if they know another way. Ok put ur hand about 5in in front of ur face. Ok blow at ur hand with ur mouth almost completely closed, u can bearly feel the air right. Ok now open ur mouth all the way like at the dentist and blow. U run out of air to quik right and u bearly feel it. Now open ur mouth like u r going to whistle and blow at ur hand. U get a longer lasting and stronger stream of air right. Cars now in days work wonders with small air related mods. If u get a bad ass intake but no exhaust then ur intake is going to waste since it can only take in as much air as it can let out. If u have an exhaust u have the perffict blend of air coming in and out. But if u go open header then u are letting to much air out. I hope u see what i am saying.

[ridge_runner]

small blocks depend on back pressure, big blocks dont really need it, thats y they run open headers

[ridge_runner]

and the dragsters headers have like a 5 or so inch long pipe on it, like a mini straight pipe

[lazysmurff]

to add to what z28 boy said...

those top fuel dragsters are not only running open headers, but look at the throttle bodies...those things will suck in lear jets flying over head. they are simply matching intake with exhaust.

and in experience, my buddies old ford truck ran open headers for a day, then hit the shop.

its been my experience that if your not sure what will happen when you perform a mod, dont. unless you have to money to fix any problems that come up.

[daveshapellSVT]

ok thanks , yea i understand the hole deal now..

[e3j1c1]

I ran my car a few days with open headers but I couldn't hear my radio and my interior stunk of exhaust. I didn't notice any change in performance, so besides sounding badass it didn't do a whole lot for my car.