mark kibort

the WCGT motor is a little more than the map and headers. I cant remember the details , but it was heads, compression, valves, cams, etc.

mark kibort

check out the pic of the GS car on the dyno. 350rwhp

hey, you were the one that told me you have never beaten a 1:38 at laguna seca, but did 1:35s last time you were there on new slicks! that sure seems like a big difference, more than .5 point. bring some DOTs and race me next time!

magnetic1

or if the higher HP car's motor has a better torque curve. You cant just compare the peak HP. There are far too many other factors.

mark kibort

you can make up for a lot of weight, with set up and tire sizes. the 928 is very wide and if you get some REAL big tires on there, you can make up for a lot of the weight disadantages. I agree though, its always better to go lighter in my opinion. im on the fence with my car, and its a tough call. lots of light cars are very very fast, but then the higher p/w cars are faster still. sometimes its jsut easier to add the weight and get some bigger tires.

mark kibort

They can be. the problem is the correction factors, thats why I always like to see the raw data (uncorrected). But at altitude where there is so much correction that is tough. but at sea level and just different days, you can get an idea of what you got. I always get two dynos a year. one in winter and one in summer. remember, the dynojet is just seeing how fast you accelerate the drums! no other factors! so, its pretty consistant on a similar day (temp pressure)

mark kibort

I did say, at any same vehicle speed. Yes, you are absolutely correct, and this is exactly the reason why they average torque and HP to give the HP to weight ratio. they assume (GTS rule makers) that a higher torque than HP value, will point to an engine that has a flatter HP curve, which would have advantages at all points other than peak HP. so, your "better torque" curve, really is a better HP curve. However, there are still flaws with this technique. one I know well would be the BMW e30 (torquer low reving engine). it has 170rwt but has only 120hp. to average it out to 145hp, is a little unfair. (in otherwords, this car would have to compete against another 145peak hp curve engine, that might have an average of 120hp if it was very peaky over its usable range. obviously, the e30 might be less than 100hp in this example, so it clearly is getting dinged unfairly. But aside from this example, it works well enough for the series .

bobt993

How do you get that? His torque way exceeds his hp ( according to his notes on his signature) and it depends on what dyno that was run on.

mark kibort

so, he does have a stout HP curve (higher torque vs HP would indicate this)
so, his HP gets adjusted to 222rwhp. which at 3200lbs, is 14.4:1. this means he has to either kill some torque, and power, which is the smart thing to do, or go up to GTS3, which he will get killed in that class. that car would be just as fast with a passenger in it, so I vote to just dump some power and put 100-200lbs of ballast in it and call it a day. its tough to drive a overweight car fast, but doable. remember randy pobst and galatti running 275lbs of rewards weight at road america and still running 2:14s!! ??????

North Coast Cab

It's GTS....
Modify the HP and Torque curves how you want them.
Locate the weight where it is most advantageuos.
Run whatever size tire/wheel combination you desire.
Modify your body for less drag and better aerodynamics.
Add all the downforce aero you can handle.

claykos

Not for the 2010 spec 3.8 motors. The old world challenge rules for the 3.6 were compression bump, 2 ring pistons, different cams...

The rules now allow for the stock 2010 3.8 cup engine which is factory rated at 450hp. They can do headers and ECU flash. That is what Sofronas told me...

mark kibort

Yep, sorry, I was talking about the older 3.6 motors. Yes, the new 2010 are beasts. I cant believe the power that the '10 cup motors make. amazing!
I got the same story from Sofro.

cgomez

BTW, are people already doing Custom ECU programs for the GTS rules (i.e. maximizing the area under the HP curve - Flat peak HP - on the rev range needed for the used gearbox)?

and is active Aero banned?

ninjabones

I'll stir the pot a bit as well as it does appear to me that this is exactly where the GTS series is migrating. Not a criticism, as the GTS series seams to attract guys that like to develop their cars, and the rules certainly have spawned a lot of tight competive racing in this region. However, the concept that it is a cheaper option than PCA GT class racing is really not accurate. I predict that in order to have a competitive car (in the very near future), you'll have to build a monster engine and then "detune" to create a completely flat HP curve at the exact threshold for your HP/weight class.

In fact, I believe we might see more cars running both NASA GTS and PCA GT classes. They'll just have to have two engine maps (one for maximimum horsepower for PCA and one retarding the timing above some RPM range for NASA GTS).

cgomez

Spot on comment Glen. GTS is Foumula Libre. A PCA Stock or Prepared car should stand no chance in GTS. Other than custom engine mapping there's infinite development that can be done regarding aero, gearing and suspension design.

The simple rule started as a way to please everyone and "run what you brung" as many people felt left out from PCA or BMWCCA b/c they had minor mods that made their cars ilegal in the Stock/Prepared classes. However, unrestricted rules in the long run promote the build up of cars way beyond the limits of current GT (in PCA) or M (in BMWCCA) classes.

Having the GTS3 winner at Nationals lap 4secs faster pero lap than the rest of the fields is a clear testament to that, and I dont thin anyone is even close to the limit of what can be done. Therefore, IMO, it is a ill advised decision to build a racecar mainly for GTS if you dont intend to go all the way (unless you dont care about trying to win at all)

jrgordonsenior

The Miller turnout, especially in GTS3 & 4, wasn't representative. Last years GTS3 winner would have been competitive with his stock 996spec w/80k miles on it had he chosen to run this year. Jay just didn't have any competition. GTS 4 was equally poorly reperesented. Had my motor not blown I woud have run GTS4 from DFL and I should have easily won that class. I'm not close to the weight/hp class minimum of 9, more like 9.8.

Perhaps as the series evolves your fears may be realized, but not so much out West.....