and estimating the cars weight at 3350lbs (car at 3200lbs and driver at 150lbs)
Center Delete: 121.4mph = 467.8bhp
Dundon Race: 126.8mph = 533.0bhp
If the car and driver is 3200lbs
Center Delete: 121.4mph = 446.8
Dundon Race: 126.8mph = 509.2
If the car and driver is 3100lbs
Center Delete: 121.4mph = 432.9
Dundon Race: 126.8mph = 493.3
Estimating the weight at 3350 gets us pretty good alignment with stock numbers at the crank... (car is advertised at 469 SAE HP)
This was the same driver, same launch, same tire pressures, same track, same rear wing removed...
This also would include the effect of ram air which we know adds power, but is hard to reproduce on the dyno. Also changing the weight of the car has an obvious effect on the numbers, but the delta stays about the same. It also looks like a center delete may lose a bit of power, but would need more data.
This is more power than we record on the dyno, but it isn't a surprise as the decklid is designed to capture air and force feed it into the engine...
You're all free to go run the numbers or play with the calculator yourselves...
The increase was enough that the race tech guys pulled him out of line and searched the car for NOS...
I'm very happy with it. In terms of affecting the cars outright performance, as such, I cant really say till I've been on the track, strip or Dyno with it - but Ill eat my hat if the car isn't measurably quicker in all situations. On a fast back road run for 150 miles it felts quicker for sure but in terms of lap times I don’t know how this will translate – Im thinking 4 tenths over a 1 minute track lap?. The DMS has given the car a different dimension and is one less reason not to rush out and upgrade to the next GT3....HIGHLY RECOMMENDED - Im a very satisfied customer! This is not a cheap product and infact the most money I have ever spent on an exhaust set up (and its only headers), for any of my cars ever. That being said its a quality 321SS unit that should last the life of the car, it is a direct fit for 991 GT3RS, 911R and likely the forthcoming 991.2 GT3, so there is a large secondary market if I should sell the car or I can take it with me to my next GT acquisition...and there is also a GT4 set for those who like to row their own gears on track!
Thanks Jamie & Charles for your excellent product, your excellent service and all your help in getting these to me. I look forward to your GT3/4/RS exhaust tips next! ~ Mark, Australia: 991 GT3 Race Headers