Exhaust Manifold (Headers) Equal Length?

[1owner69Elan]

The TTR exhaust manifolds are stated to be tuned for length etc.

Measuring a set of TTR headers taken off of a 26R, I find that the paired 1 and 4 are close to the same length. But, the paired 2,3 are about 4" difference (3 is longer). I did read somewhere that "equal lengths means within 4"". All four lengths are within this 4" tolerance.

Looking at the stock cast manifold of the S4 SE there is obviously no comparison to the TTR. The stock lengths are quite different as well as much shorter overall.

Probably moot as to what I am going to put on the car as I am not sure there is a better set of headers out there than the TTR without trying to customize. My engine that has just been assembled is on the high end of output for a road car. Measured on the dyno with 1-5/8" 4:1 headers at 181.3 bhp @6900 and 142.9 lb-ft @ 5100. The TTR headers I am looking at are also 1-5/8" but 4:2:1 which should shift the peaks to a bit lower rpm.

[stevebroad]

4" seems a lot, I wouldn't call that an equal length headers system.