FS: DKF Section 1 w/Resonator

[N55_Mike]

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Hey guys, I have this amazing condition DKF section 1 with Resonator only I picked up, Selling because I found a Supersprint section one straight pipe to be a bit louder. I also separated the resonators from being 1 complete section 1 peice to make installation 50% easier. I will ship within the ConUS only, as shipping out will be expensive. Cheers!

ps: PM for pictures.

[No_Dominion]

Just curious, were you running headers with the DKF section 1? I'm considering changing out my section one for just a resonated one, but I'd like the opinion of someone who ran a similar setup.

[N55_Mike]

Yes I was running Euro headers. These DKF resonators remove a ton of rasp, which is why I loved them so much. Sound is perfect also, not loud.

Originally Posted by No_Dominion

Just curious, were you running headers with the DKF section 1? I'm considering changing out my section one for just a resonated one, but I'd like the opinion of someone who ran a similar setup.

[inTgr8r]

Originally Posted by No_Dominion

Just curious, were you running headers with the DKF section 1? I'm considering changing out my section one for just a resonated one, but I'd like the opinion of someone who ran a similar setup.

We had Caddyshk's car set up like that for a year and it worked out great except the catless smell....
We put the DKF CATs in for emissions testing and there wasn't much change so they are still in.
That was also with a R.Eng Xpipe.

I have the same setup except I've run DKF CATs from the beginning.
The Xpipe definitely brought in more rasp, especially when cold.

[No_Dominion]

Originally Posted by inTgr8r

We had Caddyshk's car set up like that for a year and it worked out great except the catless smell....
We put the DKF CATs in for emissions testing and there wasn't much change so they are still in.
That was also with a R.Eng Xpipe.

I have the same setup except I've run DKF CATs from the beginning.
The Xpipe definitely brought in more rasp, especially when cold.

Were there any measurable performance improvements versus the stock cats? They look like a quality piece, but I'm not after sound changes/improvements from this potential mod. I realize it wouldn't be much, but every little bit adds up.

[N55_Mike]

I personally think it might give out a couple morextra horses, but I don't have dyno results..

Originally Posted by No_Dominion

Were there any measurable performance improvements versus the stock cats? They look like a quality piece, but I'm not after sound changes/improvements from this potential mod. I realize it wouldn't be much, but every little bit adds up.

[pokeybritches]

As soon as I can hit the dyno again, I can give you results. I will say the gains were significant on my supercharged car with CPI stepped headers. Once I added the catless headers, the stock s-pipe became the restriction. NA guys with catted headers have noticed less gains.

FWIW, here's my dyno results:
Z4 non-M on my local Dynojet - 285 whp

Z4 non-M on TTFS's Dynocom - 266 whp (~7% lower)



Z4M / stock exhaust / Dynojet - 393 whp

Z4M / CPI stepped headers / Dynojet - 393 whp (needed tune to realize gains due to alpha-n tune of supercharger)

Z4M / CPI stepped headers and DKF s-pipe (100 cell cats) / TTFS Dynocom - 393 whp

Z4M / CPI headers and DKF s-pipe, TTFS tune / TTFS Dynocom - 417 whp


My gains were fully dependent on the correction factor between dynos. If you use 7%, it would be 27 whp for the DKF s-pipe. However, I want to get another final dyno on the Dynojet to confirm my final numbers before I say for certain.

[No_Dominion]

Glad to say I pulled the trigger on these. A little out of order from my planned mod timeline, but too good to pass up.

[Beedub]

Originally Posted by pokeybritches

As soon as I can hit the dyno again, I can give you results. I will say the gains were significant on my supercharged car with CPI stepped headers. Once I added the catless headers, the stock s-pipe became the restriction. NA guys with catted headers have noticed less gains.

FWIW, here's my dyno results:
Z4 non-M on my local Dynojet - 285 whp

Z4 non-M on TTFS's Dynocom - 266 whp (~7% lower)



Z4M / stock exhaust / Dynojet - 393 whp

Z4M / CPI stepped headers / Dynojet - 393 whp (needed tune to realize gains due to alpha-n tune of supercharger)

Z4M / CPI stepped headers and DKF s-pipe (100 cell cats) / TTFS Dynocom - 393 whp

Z4M / CPI headers and DKF s-pipe, TTFS tune / TTFS Dynocom - 417 whp


My gains were fully dependent on the correction factor between dynos. If you use 7%, it would be 27 whp for the DKF s-pipe. However, I want to get another final dyno on the Dynojet to confirm my final numbers before I say for certain.

so with the 100 CELL cats you made significant gains or am i reading that wrong?

[pokeybritches]

Yes, I made some pretty big gains. With catted headers, the gains are less significant. On cars with Euro or aftermarket catless headers, the gains are more pronounced. Catted headers are the biggest bottleneck, and once they are removed, the stock s-pipe becomes the bottleneck.

[No_Dominion]

I'm not expecting too much, but once temps drop back down to where they were during my last dyno run, I plan on doing another run post install to see what gains I make. I intend to do another run following each subsequent performance mod I do, partially for personal knowledge, and partially to help take some of the guesswork/butt dyno out of the equation for others.