Jim bailey - 928 International

More info on the ..."HKS's CT230R Evo is far from your ordinary rice burner. It was meticulously constructed in HKS's special projects workshop. The chassis has been significantly reinforced to reduce flex. The driver's seat is pushed back even with the B-pillar for better weight balance. The body is completely lightweight dry-carbon. Plus, the 4-cylinder 4G63 engine outputs 550 HP with the help of an HKS GT3037S turbocharger. According to Options Magazine, the whole package weighs in around 2,200 lbs making for a rather favorable power to weight ratio. The Japanese tuners must also know something about the benefits of balancing unsprung weight versus the amount of available traction, as they all seem to prefer rather narrow tires. The CT230R performed its record breaking run on 265-wide Yokohama A048 DOT tires. More details can be found in Turbo Magazine's feature article on the Evo...."
So 2,200 lbs, all wheel drive , 550 HP , on 265 tires on all 4 corners....should be FAST ! Really FAST

Imo000

265s all the way around is quiet a bit don’t you think? The HP distribution to each wheel is about the same as what a stock-ish 928 puts down. Here are the rough number if the hp distribution was even between the wheels (usually there is a bias towards one set): 550hp / 4 wheels is 137.5 hp. That’s not all the much for a 265 wide tire. A rear wheel drive car, like the 928 would put around the same power to each wheel too and they are only 245s. So 265s in each corner, especially if they are slicks or DOT slicks, of the Evo are adequate. Or am I missing something?

Charley B

99.9% of road racers say "Oh ****!" as they slide off a slippery road toward the ditch. The other 0.1% are 928 racers, they say "Hold my beer, and watch this."

Jim bailey - 928 International

Ok .." am I missing something? " yes cornering ability and braking plus the need to do more than one of those at the same time. Powering out of a corner is key for good lap times. With only 198 RWHP on wide dot race 225x50x15 Kuhmos I can easily spin the old brown 1980 really easy !
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mark kibort

4x4 helps here, but it was proven that the heavy 3500lb audi RS6 in WC GT, was running some spectacular performance with 305s on all 4 corners.

265s are not that small, in proportion to the weight of this car. (only about 1" narrow compared to my 305 rear tires) There are a few World challenge touring cars that run near as fast as mark anderson with a heck of a lot less hp. (and some less weight as well, AND 235 tire sizes!) 1:35s at Laguna seca?
Marks best time at laguna seca with DOTs has been 1:34.8, but with the new track, call it 1:33s probably. The point is, set up is pretty important, and not many cars just spin the wheels even in 2nd gear when pointed straight ahead. any car can be pitched sidways or broken loose if the power is not applied with care .

i drove Joes stroker 928, Marks stroker and also the Devek machine. all had tons of power. if i was straight, and those tires were heated up, they didnt brake loose at all in 2nd gear.

The Evo with its high quality DOTs (probably better than hoosiers) and the width of the car (much wider than stock), Aero, along with 4x4 power, and a highly tuned suspension would come off the turns with amazing force, and rocket down the straight like a MOTOGP superbike! Not to mention the braking and cornering capability of a very light and balanced race car!

By the way, the Evo in this event is rumored to be more like 800 hp. After seeing it come down the straight at buttonwillow, i believe it!

mk

mark kibort

I dont know about the HP distribution with the evo 4x4, but i bet there is some fancy electronics behind that. obviously, there is a balance of the power on all 4 corners. With 800hp rumored, this thing is a rocket. based on the time, and how much faster it ran the circuit vs a top WC GT car, It basically is near the performance of ALMS GT2 or even possibly GT1. This car is supposed to be one of the fastest in Japan.
I think Mark Anderson got a flavor of these types of cars at the JGT event at Cal Speedway. These cars ran around him like he was a pylon. some of them had inboard suspension, a lot of HP and were extremely light.

considering the force it takes to break the wheels loose when in a straight line, I'm sure you could equate certain acceleration rates of lower hp cars at the edge of traction (like mine in 1st gear at near 5000rpm when pointed straight) with speeds higher where this same "edge" would be found.

If hp doubles, what would the speed have to be to create the same acceleration rates. I think at first glance that speed might only be 20-30% higher. Ill have to think about that one.
edit: If im breaking loose at 50mph, it takes about double the HP to do this at about 60mph. (about 25% greater vehicle speed with double the HP creates near the same acceleration rate, which would provide near the same traction issue)

mk