my own experience with headers:

996tt bone stock.....

first test with ported header......spool a little better
second test with B&B Header (it is a K16 Header with small diameter) spool a little better than a ported oem header

GT2:

with B&B Header turbos spool a little better at low rpm


second Test with a special K24 Header with Merge Collector and greater diameter (so the K24 hotside must ported a little)

better spool at mid and a noticable gain at higher rpm....

sound with headers are different .....

After all it is for the money only a little gain to get with headers...better do it a last...

A Intake (like Speed Tech Complete Kit) mod. Turbos (K24/18) does more for the money....

just my only feeling about headers hope it is written so you are not confused about

 

Do you have any dyno data or spool data by chance? Butt dyno data can be very deceiving

 

Something about the exhaust manifolds being good to 700 "real" hp...for Karol...he probably means "euro" ponies.

 

he pretty much states that they are good for up to 700 hp and tuners rape people for headers...
damn Polacks

 

Since I'm fluent in Polish I'll bite:

I'll tell you more, serial collectors will work without a problem up to real (I suppose he means whp) 700 hp. It is amazing how the remaining tuners cheat people. I'm thrilled that you're tuning porsches.

 

I really have to chuckle with this header issue.

Someone builds a set of "headers" and if they don't make power the header is at fault. It all cases it will be the fault of the person building the header.

Just like anything else ...... when you get to the top, little gains become far more expensive. With that being said, headers are not one of the first thing anyone should add to get the best bang for the buck.

I take issue with anyone who says headers do nothing.

We went this route about seven years ago. We found:

1) The stock headers were pretty good, however proper porting will improve them.
2) The shorter you keep the developed tube distance ........ the better the header.
3) If you do not know about "harmonic distortion, what causes it and how to eliminate it ...... then you do not belong building headers period.
4) You need to use a correct material thickness coupled with the right ceramic coating and rap so as not to lose any more heat than you have to.
5) The tube diameter must be matched (designed) to the torque and power.

Follow the above and headers will make power on a 996tt motor. We proved this will header only dyno's back in 2003. We made five different sets.

Headers can make power, however if you understand 1 thru 5 above you will also understand that the power will be expensive.

 

Not surprising at all.. Nice to see AMS did their homework as usual.. I looked at my M5 and didnt even bother to swap headers.. The same as the GT3.. If it aint broke dont fix it..

 

Sounds like it's all sciance of passing gas.

 

No wonder your fluent you're from Chicago, it's like the 2nd Poland.

 

In turbo street cars where the pressure ratio of exhaust to intake is worse than 1:1 (30psi of exh BP to 20psi of intake pressure for example), headers will basically do nothing. To me 5hp at 700whp for a customer to spend $2500 or more is virtually 'nothing'. When the backpressure ratio gets closer to 1:1 or less then you can start taking advantage of a properly designed header.

Valve timing events along with backpressure also play a role in header length. I've always used thick walled tubing for turbo headers, mostly for reliability. The prototype unit for the 996tt we built was .120" wall S.S.






Here is an example of a header we built. This a motor combination we built from scratch, with no testing or changing of parts. The intake manifold and exhaust manifold were designed and made based on calculations. The 1035 hp was made on the 3rd dyno pull and I only stopped because we already destroyed the competition. That setup would have made 1100-1150hp on 100 octane fuel out of a 2.0L, maxing out the turbocharger.




Once we get our billet K24's on there I'll do a back to back test with the stock headers, ported stock, and then our header, for a final check.

-Martin

 

i like the look of headers so if they did not hurt performance, i would purchase based on that alone.

 

no i think he means that us tuners dont make real horsepower and we over exagerate as oppose to the euro tuners where the make the real power un exagerated ... beeing that they are always underpowerd and we make power over here.

in that case i think means euro donkeys!

 

Have you experimented with a divided manifold?

 

I was making 890 rwhp on my last car at 1.6 BAR...on ported, but otherwise stock headers.

 

I saw your underneath your (old) car and I was stunned. Go Protomotive!