I am going to be beta testing some headers. Having seen them I expect good results. If all works out well I am going to arrange a group buy.

I expect to gain HP on the top end.

Any thoughts????

 

My understanding for headers on a 993tt is that stock are best up to a certain hp level (say 60-130mph in 8s 4WD/1500kg) after which the big bore units as used on the GT2 EVOs are needed to work with the bigger K26, external wastegate turbos. The main issue for a street car is that the packaging does not allow heat exchangers to be used and one loses any heat - which is unacceptable in most climates.

Apart from looking shiny and nice and smooth inside, what has been promised to you with these new units ?

 

TB,

I know the factory headers are real restrictive near the outlet. The new set looks real promising. I suspect that top end power will improve with the better breathing. I also expect lower CHT's and EGT's from the reduced back pressure.

The header are available with and without heat exchangers. The set I am beta testing may not have heat. If that turns out to be the case I will just route a 3" SS tube from the rubber boot to the cat pipe and pick up a little heat from that. Since I live in California its not a major issue.

Two different people have offered up the AX22 to allow me to test my car. I will add it to my dyno testing proceedures and see how this next change affects things.