On our Buddyclub DC5 in ATCS we usually ran 280 bhp because it was very reliable. but on the 2009 UKTA car we ran 305bhp on our modified RBC and 70mm TB which was not quicker at all on short circuits but on Silverstone and Snet it was a second quicker per lap, on fast heavily controlled one off lap situations (ideal condition tyres...all temps...wind...track condition ...time of day ,,,etc)
On the Nippon challenge 2011 car we ran 275bhp because its a 15 lap race and not a timed superpole style, so bhp makes no difference to race pace time and rythem . we still won every GT300 race...and were even faster that the GT500 class in all but one race(achieving outright wins) ....you guys should just get your NA heads on and go out there and kick some ass...
We have built the same engine for many many road going DC5 and EP3 cars with exactly the same bhp within 1-2bhp. they are still out there going strong...
Long live NA tuning.
P.S. Chassis are more important for winning races than power !!!!! just an observation over the last 30 years of my racing career... ^__^