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-   -   Team 949 Racing Thunderhill 25 Hours (https://www.miataturbo.net/race-prep-75/team-949-racing-thunderhill-25-hours-61707/)

ckearns 12-07-2011 02:09 PM

Lesson learned from the 2011 season... Don't send in dyno sheets with reclass requests. Just tell him max power and one of the other two variables and let him solve the equation.

Torque is not factored in to base classing or power in the TT rules as they're currently written.

The only ones that need the dyno results are the TT directors, and all they look for is the max power number.

Chris

falcon 12-07-2011 02:21 PM


Originally Posted by bellwilliam (Post 803479)
problem with NASA classing is that it is hq/weight ratio. so you want an engine that makes 170whp from 3k to 7k rpm. Rotrex is a peaky engine, it won't work with NASA.

Maybe, but a Rotrex'd 1.8L making 170HP from say 5000-7000RPM with a restrictor would still be fast, and I would think more reliable than a turbo motor. My motor makes 110whp at 3000RPM and 297whp at 8000RPM. But I'm never driving at 3000RPM on the track, so I don't really notice it.

falcon 12-07-2011 02:23 PM

How would they class a car like mine for instance? High HP, but low torque? Dyno is in link... didn't want to dump a big pic in this thread.

http://forum.miata.net/vb/showpost.p...6&postcount=68

deano 12-07-2011 02:27 PM

If we're still talking about endurance racing, you've then got to figure in the additional time you'd spend in the pits to fuel the car and change tires/brakes with a much faster car. The cars Emilio and William built are pretty close to the sweet spot of speed, fuel efficiency and consumables consumption (tires/brakes) to kill any and all comers in the classes that only allow jug refueling and 1 tire changes in the hot pit.

That being said, oh how I would love another 50-75 HP in the exact same platform to race in the 25!!! It would completely change our relative position in the speed food chain on track, as we'd then be just as fast as all of those big E46's down the straights.

Cheers,

Dean

Efini~FC3S 12-07-2011 03:15 PM

Big congrats to you guys. Neither of our cars had much luck this year. For the 2012 Civic Si the 25 hour was basically a test for the Grand AM season next year so we were never really concerned about winning. On the other hand our RSX team was poised and fully expecting to win. After about 10 hours we were swapping the E1 lead with the Scion team and actually swapping overall positions with the Crusher. Our car was the fastest out right in E1 (fastest lap of 2:00.3 set in Hour 21, lol) but we could only go about 70 minutes on fuel (more than the Scion but not as much as the 949 miatas).

Unfortunately we changed the equivalent of five dampers throughout the night. One of our drivers had a big off in the kink, which he blames on spilled oil or water. He went about 1000' up the hillside and basically destroyed the whole front left suspension. We spent about 2 hours replacing the front left suspension and fixing the splitter, etc. After a few more hours of running the front right damper gave up the goods, prompting a full front suspension replacement because apparently we had run out of common spares. The crew built a whole new front damper set up using some random H&R dampers, one guy had to build a damper mount out of a wheel spacer using a 4 1/2" grinder.

Anyway, a disappointing race for the RSX team, even though I think we ended up finishing fourth or fifth in class despite not running for over 4 hours.

Personally I had a pretty good outing, ended up setting the second fastest time overall in our car and had the lowest average lap time and lowest lap time standard deviation. I'm pretty pleased with this considering all the other drivers in the car had been to the 25 hour before and had driven the car before. The only driver faster than me over a single lap is a Canadian Touring Car driver.

Finally, big LOL to the guy who said a FWD car would be awful for the 25 hour. Coming from a team that has finished on the podium OVERALL with E1 and E2 cars, I can say that a well set up FWD car can hang no problem. If you're on the right tires (ie BFGoodrich R1s) you can make the fronts last 3 stints no problem (even the front right). You end up only having to change the rear tires once, maybe twice the entire race.

The lesson to be learned is the most important thing is to run 25 hours of the 25 hour race. Any stoppage greater than 5 minutes (ie fuel spill or basically any mech. failure) can easily put you out contention for the class win. The fact that Enzo beat all of the E0, E1, and E2 cars is a testament to just that. Despite the fact that we had a car that was easily 4s a lap faster than Enzo, we had no chance after the first mechanical failure.

Congrats again, as far as I could see you guys performed flawlessly.

jacob300zx 12-07-2011 03:50 PM

I want to see you guys get more sponsors and field a 3 car team next year. I would also like to see you guys run a live webcam where fans/customers can watch drivers/crew/etc update the viewers on whats going on. Your def going to need some PR voluntiers to take pictures/vid/webcam/facebook/twitter/forums etc. the coverage of your team was... uh ...lacking, compared to the epicness of what you achieved.

Is there any in car video from this year?

rharris19 12-07-2011 04:34 PM

Like I said in the GoPro thread, the new Hero2 will have the ability to live stream over an internet connection with an adapter that will be coming out in February. We will be making an entire system for our lemons car that you guys are more than welcome to borrow for the next T25 race. Hopefully it will have several cameras integrated into one screen and possibly a heads up overlay from on-board data acquisition.

miata2fast 12-07-2011 04:46 PM


Originally Posted by Ron Alan (Post 803331)
He ran with the AMG team in a MX5 in E2...which was both Crusher and Enzo's main competition. They passed Crusher with about 15 minutes to go but couldn't get back to Enzo who had about a 8 lap lead at the time. Like both these cars, mechanical issues played a big part in their finish.

Thanks for the update.

Bob (Beau's Father) campaigns a GT1 Corvette, and is building two Scions to run in the Motorola Cup at Daytona in February. I plan to witness the carnage.

bellwilliam 12-07-2011 06:55 PM


Originally Posted by jacob300zx (Post 803551)
I want to see you guys get more sponsors and field a 3 car team next year. I would also like to see you guys run a live webcam where fans/customers can watch drivers/crew/etc update the viewers on whats going on. Your def going to need some PR voluntiers to take pictures/vid/webcam/facebook/twitter/forums etc. the coverage of your team was... uh ...lacking, compared to the epicness of what you achieved.

Is there any in car video from this year?

unfortunately, Thunderhill has the worst cel reception of Californian tracks. my AT&T and T-Mobil wouldn't barely work as a phone, there is no 3G. We also had some Verizon and Virgin, both had issue too.

there is in car video. but can you imagine sifting through a total of 50 hours of video ? it is going to take a while.

emilio700 12-07-2011 07:25 PM

2 Attachment(s)

Originally Posted by Efini~FC3S (Post 803537)
The fact that Enzo beat all of the E0, E1, and E2 cars is a testament to just that. Despite the fact that we had a car that was easily 4s a lap faster than Enzo, we had no chance after the first mechanical failure.

Congrats again, as far as I could see you guys performed flawlessly.

Enzo actually got a hub, rotor and front pads during the race and also did part of a lap without a left front wheel. Hence the flat spotted rotor. Within the first two hours a cam angle sensor failed so we had to diagnose and replace that. Three unscheduled stops for mechanicals. Enzo was not without it's share of down time in the pits. Our best guess is about 12 laps we lost which would have put us at about 654 laps and that's with the 6-7 seconds off regular pace, slow conservative speeds we ran for the last three hours knowing we had it won if we didn't break.

https://www.miataturbo.net/attachmen...ine=1323303924

jacob300zx 12-07-2011 09:04 PM

William look into a cell phone repeater. It will take the small signal your getting and boost it. Older laptops with the side slot for the aircard can take those older square aircards and those can have big antena's put on.

njn63 12-07-2011 09:46 PM


Originally Posted by bellwilliam (Post 803479)
problem with NASA classing is that it is hq/weight ratio. so you want an engine that makes 170whp from 3k to 7k rpm. Rotrex is a peaky engine, it won't work with NASA.

Just speaking out loud but if you can control the boost from 3k-7k you could produce a flat line at 170 whp. ;)

bbundy 12-08-2011 02:17 AM


Originally Posted by emilio700 (Post 803631)
Enzo actually got a hub, rotor and front pads during the race and also did part of a lap without a left front wheel. Hence the flat spotted rotor. Within the first two hours a cam angle sensor failed so we had to diagnose and replace that. Three unscheduled stops for mechanicals. Enzo was not without it's share of down time in the pits. Our best guess is about 12 laps we lost which would have put us at about 654 laps and that's with the 6-7 seconds off regular pace, slow conservative speeds we ran for the last three hours knowing we had it won if we didn't break.

https://www.miataturbo.net/attachmen...ine=1323303924

That rotor hat face and the stud holes sure look like it was running with loose lug nuts a while before the studs probably broke I’m guessing.

Bob

ZX-Tex 12-08-2011 09:20 AM


Originally Posted by njn63 (Post 803671)
Just speaking out loud but if you can control the boost from 3k-7k you could produce a flat line at 170 whp. ;)

All ears for a reasonably priced, reliable, efficient way to do that with a centrifugal supercharger. Blow-off pressure regulators do not meet this requirement.

Efini~FC3S 12-08-2011 10:10 AM

K20 powered miata would be the sh*t. 210 whp (with simple i/h/e + tune), 150wtq, 8000 revs, reliable, easy to drive and good fuel economy. If you could engineer a swap kit / mounting solution that would survive the 25 HR you would have a killer car. You would probably want to use the s2000 transmission, which we have proven is reliable enough to survive the 25 HR. This swap might be able to fit into PTB, more likely PTA which puts you in E1 or E0?

K24 w/ k20 head would also be badass but might be a stretch to stay in E0. 250whp, 200 wtq (again w/ simple i/h/e + tune) 8000 revs, reliable, decent on fuel. The Fantasy Junction RSX (I believe the car that Crusher had a coming together with) had the same k24/k20 motor in their car for 2.5 25 hour races. 60+ hours at TH on one motor.

Efini~FC3S 12-08-2011 10:15 AM

Sorry for the double post but personally, I wouldn't take a turbocharged car to the 25 hour. How many turbo cars finished the race this year? The Scion had major problems, the former Grand AM (professionally built) Subaru had major problems. I can't think of a turbo car that ran the whole race without engine problems this year. HPD did it last year with the CR-Zs but for me personally, I would stick to a N/A car.

falcon 12-08-2011 10:23 AM


Originally Posted by ZX-Tex (Post 803805)
All ears for a reasonably priced, reliable, efficient way to do that with a centrifugal supercharger. Blow-off pressure regulators do not meet this requirement.

Back when I was researching pretty much every bit of info on the net about Rotrex's, I found a guy with an s2000 who had before and after dyno sheets from IIRC a C30-94 and C38-xx (forget which one). He overlayed the graphs and there was no loss in power anywhere down low from going to the bigger charger. There were gains everywhere. Based on the fact I am making about 4PSI and 110whp at 3k and with a C30-94 Rotrex geared to it's max at 8000RPM, if you were to go up one charger size (like trackdayhookey's car), lower the RPM limit to 7000-7200RPM and run a properly designed restrictor and spin the Rotrex to or near it's MAX, I think it's very plausible to have a 1.8L motor that can have flat power from 3000 (ok if not 3000, maybe 3500-4000RPM) all the way to redline.

I bet if I were to drop my RPM to 7000 (and gear the Rotrex appropriatley) I would pick up 20+- WHP at 3000RPM and a bunch of torque. Now swap that C30 for a C38, and I could see another 30whp gained at 3000-3500RPM. Cap the power with a nice venturi restrictor and BAM. The best part about a system like this, is the abcense of relying on something else to control boost. No boost spikes, no broken wastegates, no blown (hopefully) motors. Keep in mind I am also running 91oct. Run race gas or E85, and I can quite easily see it possible to do the above mentioned.

luder_5555 12-08-2011 12:18 PM


That rotor hat face and the stud holes sure look like it was running with loose lug nuts a while before the studs probably broke I’m guessing.
We are still not exactly sure what happened. We don't know if three of the studs broke and this allowed the 4th to be loose and as it worked itself free over a half lap it made those marks, or if it just plain was loose.

What we do know is that I tightened it, then while we were doing something else on the car, someone else followed behind me and tightened it some more, so being loose SHOULDN'T have been an issue, but who knows for sure. Good news is that it didn't effect that car's finishing position.

jacob300zx 12-08-2011 12:20 PM


Originally Posted by Efini~FC3S (Post 803821)
K20 powered miata would be the sh*t. 210 whp (with simple i/h/e + tune), 150wtq, 8000 revs, reliable, easy to drive and good fuel economy. If you could engineer a swap kit / mounting solution that would survive the 25 HR you would have a killer car. You would probably want to use the s2000 transmission, which we have proven is reliable enough to survive the 25 HR. This swap might be able to fit into PTB, more likely PTA which puts you in E1 or E0?

K24 w/ k20 head would also be badass but might be a stretch to stay in E0. 250whp, 200 wtq (again w/ simple i/h/e + tune) 8000 revs, reliable, decent on fuel. The Fantasy Junction RSX (I believe the car that Crusher had a coming together with) had the same k24/k20 motor in their car for 2.5 25 hour races. 60+ hours at TH on one motor.

Although I like your idea and the K20 is an outstanding motor. Emilio has the resources to build an NA miata motor to around 180-220ish.

luder_5555 12-08-2011 12:30 PM

^ As I was told all week about the motor, "You betcha." I don't think that the car needs more power, unless it is going to run E0/1. It also doesn't really need any more low end. A K20 would be a great motor to have, but as long as they were to do a motor swap for purposes of gaining more power to run E0/1, I think that there would be several contenders. Plus, and I could be wrong, but isn't a K20 a rather tall motor? I remember seeing an F20 NB that had the motor as high up as possible without hitting the hood, and the lowest point on the car was still the oil pan. I would assume that the K20 is dimensionally abut the same.


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