Longtube headers = no power???????

[raiders03]

I just had the Kooks longtubes with cats installed and got no gain at all. I actually lost some low end torque. Anyone ever hear of anything like this? I am disappionted to say the least.

 

[SVTdubs]

this subject has been beaten in the ground with no return... no answer..

I am leaving the stock manifolds in place or maybe go with shorty's. I want to keep some back pressure in the car but I want it to be a bit louder!

 

[hj16]

Originally posted by EatonLS-1s
I just had the Kooks longtubes with cats installed and got no gain at all. I actually lost some low end torque. Anyone ever hear of anything like this? I am disappionted to say the least.

How much boost are you running?

 

[raiders03]

00SVTdubs
So you have heard the samething before????
hj16
I have a 2.8 pulley.

 

[03Steve]

I am taking mine off. $1,162 for no gain. :gt:

 

[Mustang Mike]

Not trying to be a smart ass but that doesnt suprise me:shrug: I put long tube on my 03 gt (i know big difference in cars) but down low it sucked even with 4.10's, all the bolt-ons and a custom dyno tune. These cars are built for back pressure and love some restriction, thats my theory at least. Honestly though since you used cats Im suprised you still had a loss down low, i thought you would have been ok. sorry to hear about your experience, its not the first time ive noticed this and wont be the last. i wont be going long tubes again unless im sure i will benefit from it.

good luck!

 

[BigBeez03]

I always thought upgrading the stock manifold to aftermarket headers would net the biggest gains out of any of the exhaust mods??? There is a good article on long tubes and the 03 Cobra in a back issue of MM&FF, I'll try to dig it up and post some info..

 

[DPS]

I have read several article that indicate that the stock mufflers are the biggest cork. I've read a lot of threads where people installing headers lost a little torque but gained a little horse on the top end. I am leaving my stock headers in place. I recently installed the Magna Flow system and love it.

 

[FordFreak]

When you run longtubes your boost pressure goes down.
So if your making the same power with less boost than you used to have then you DID GAIN!!

I pulled 304/306 with longtubes and densecharger on my 01 cobra.

 

[SolidSnake]

Did you gain anything UNDER the curves?

 

[raiders03]

I did not gain anywhere. The curves were identical except I lost a little low end torqe.

 

[CWCobra]

Don't believe everything your read in the magazines. They are paid to print what the advertisers say. Magazine articles are often less than the truth. At least that's been my experience. Sorta like infomercials on TV. No difference.
Later,
CW

 

[raiders03]

CWCobra
I believe many people on this forumn have had significant gains with these headers. People with headers post your experiences.

 

[Onelfastlride]

Do a search on the Lightning Boards, you'll find a similar theme. Some guys report paying $2500 for a full exhaust and gain nothing. Others report some gains. But you really wonder how many gain little or nothing and don't say anything.

Who knows?

 

[AMB]

LT HEADERS

When you install LT Headers/ Up Grade Exhaust Systems, you will loose some boost and sometimes some HP/TORQUE. Headers are good for HIGH HP/BOOST CARS. I run the Bassani Mid-length Headers with over 550 SAE RWHP.

AMB

 

[2F2F]

The Terminator is a peculiar beast, seemingly resistant to gains from long tube performance exhaust manifolds. Perhaps the drop in backpressure upsets a previously balanced cylinder vacuum state, thereby disrupting scavenging. Perhaps the gains from aftermarket manifolds are the direct result of improved heat dissipation, and not improved flow. The jury is still out on this one...

 

[FordFreak]

Oh shutup Adam...
:burn:

;-)

 

[moridin2004]

I don't mean to be an a**, but cars do not like backpressure at all. What they do like is an exhaust that flows exactly the amount the motor puts out. Any restriction loses flow up top where horsepower is important (torque over time). If they are too big, then you lose torque, but not because of lack of backpressure; exhaust gas reversion and other factors play into it. If you are running a big blower (i.e. Kenne Bell) then you can take advantage of the higher flow rates of the long tubes.

 

[03Steve]

Originally posted by moridin2004
I don't mean to be an a**, but cars do not like backpressure at all. What they do like is an exhaust that flows exactly the amount the motor puts out. Any restriction loses flow up top where horsepower is important (torque over time). If they are too big, then you lose torque, but not because of lack of backpressure; exhaust gas reversion and other factors play into it. If you are running a big blower (i.e. Kenne Bell) then you can take advantage of the higher flow rates of the long tubes.

I have a bigger blower... :shrug:

 

[tommygun]

the bore and stroke of the 4.6L affect the amount of power a header will make. I have seen 600rwhp cars gain a whopping 7rwhp with long tubes over stock manifolds. I will just keep my non leaking stock ones on the car till I change the power adder