has any one use these headers. They claim a +4 hp/ +3 TQ increases. They claim a stock xB puts out 78.82 hp/ 81.82 TQ on the dyno, then add their header and you got 82.79 hp/ 84.86 on the dyno. I removed my muffler alone, yes the cats are still on the car, note: only mod to the engine/exhaust area at the moment, and ran on the dyno putting out 89.4 hp/88.6 TQ. Seems kinda of a bad deal. I gained almost 11 hp/ 8 TQ by spending $40 to build a pipe to extend the exhaust pipe to the rear of the car. Any one know if they what they are claiming the stock hp to be is correct?

 

dyno numbers vary between the places you get it tested at... i bet if you had dynoed before and after... it would be much more realistic...

nobody gets 11hp from a cat back exhaust...

 

Never know, with no muffler, or any thing to cause restriction on the exhaust , ya never know, nothings impossible, only improbable. There is a dyno here in town i heard, so i plan on trying it there, to see what happens.