25hrs at Thunderhill
 

My dad lives near Thunderhill raceway and saw the last few hours of the 25hr race. He said there were quite a few "Mazdas" up there. He's a Corvette man (owns 3, none run) so by Mazda, he means Miatas. He didn't tell me much about them so I don't know if they were FI or NA.

How doable would a turbo Miata be that can run 25 hours at near 100% power? What would the max hp be limited to? The temprature probably didn't go much above 50 and the humidity is probably didn't go below 60% (always fog in the valley in December).

Frank

A turbo miata could easily swing that provided proper tuning and a driver that knew how to use the engine without fragging it. I won't even try to guess how much power you could run.

I don't know that I would want to run 20 minutes at 100 percent power in a well-turbo'd Miata, unless it was on the salt flats. Still I don't think a 250-300 hp Miata would stay on the ground that long with faster gearing:gtfo:

I think that the turbo miata would have to be pretty well sorted to last a 25 hour race with lots of attention to cooling, but it can be done.

FWIW, I ran my "shitty GReddy kit" (quote via jayc...haha :) ) at 15psi over 2 days with four 20+ minute sessions each day at a track day weekend without any major issues. I know braineack runs his at HPDEs too. Granted running at the track sure makes you track down all the "bugs" in your system, but it can definitely be done.

Assuming stroked out to 2.0 liters and a dedicated racing set-up; I think 300hp should be possible. A NA race engine should be get 230hp. Cooling would seem to be the top issue but the cool weather should be a big help.

Obviously I'm completely talking out my ass here.

i gathered... an NA miata has rarely if ever approached 230 hp.

Well, I was extrapolating quite a bit. Keith, from FM, is claiming over 100hp per liter in his street worthy 1.6 Seven. I assumed that with race cams, no cat, no muffler and an 8k rev limiter that a 2.0 liter could make it that high. I guess the heads would become a bottleneck at some point even if heavily modified.

FM has flow numbers for their modified heads on their page. I imagine a theoretical max NA hp could be calculated but I don't know how.