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Grant

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Grant last won the day on September 20

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  • Location:
    Gainesville, FL
  • Gender
    Male
  • ChampCar Team Name
    Flatout NEMESIS
  • Car 1 Year Make Model
    2009 Mazda Miata

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  1. Yes though I did want to try without it. NCs run a lot more caster than NA/Bs so it's probably needed.
  2. Yes of course we move as much weight backward as we can. The ECU is on the passenger firewall, as far as the bulk of the OE EFI harness would reach. What we have as a fuse box is near it. The center bar was not heavy and was probably a mistake to remove, since it probably keeps the frame rails from bending inward in certain front end impacts. We originally did it because we wanted to seal the radiator to the hood vent in WRL.
  3. What? That's just the center engine access port thingy. There's a lot more metal behind it. We just removed the whole thing since it doesn't seem to be structural and weighs 2 lbs. The Spec MX5s probably need a few of the things that mount to that plate, so they cut a hole in it instead.
  4. Correct I've never run a fan on any ChampCar. They're only useful when closely drafting another car of almost the exact same speed, which basically never happens. At CMP in 95F? degree weather we saw a peak of 190F coolant temps. This is with the stock radiator, lots of ducting made from factory plastics, a non-vented hood (because no windshield), and a small inlet restriction in the form of a fairly fine metal mesh over the radiator. A car which can vent its hood should be able to do better on cooling (and downforce). Aside from the sealed hood we don't have much blocking airflow out of the radiator though, relative to most NCs. I assume the air goes out into the fenders. If we'd kept running the car I was going to put a lot of time into reducing under-hood pressure.
  5. I've done extensive brake distance testing with ABS vs. none. I run ABS. The big problem without ABS is left-right bias. Without it you can only brake as hard as your weakest tire, which is almost always opposite the driver's weight. In some cars I found the fastest way to stop is actually with a locked-up right rear tire, simply because this results in more braking being done by the other wheels. There's one CAN bus connecting the ECU to the ABS module (and to the stock dash, if you have that), and as far as I know it's not required for ABS operation. The protocol is fairly simple, and we use it to log individual wheel speeds. The result is more data and less wiring than you'd find in a non-CAN system.
  6. The rotor gets far hotter than a vented one, and that heat gets transferred to the hub. Though S2000 guys have told me simply ducting air to the back side of their solid rear rotors helps a lot. My thought was the solid rear rotor contributed to the hub failures seen in the Global MX5 Cup cars.
  7. The RX8 stuff is bigger and lasts longer. I also knew I didn't want to run a solid rear rotor (cooks wheel bearings and breaks hubs), and only upgrading the rear to RX8 would throw off the brake bias even more than the full RX8 stuff does. They are very heavy but in 2020 the Wilwood stuff would have cost a bunch of points. Yes I have a Wilwood kit pieced together using their 12.88x0.81 rotors (160-9960 and 160-9959, 10.2 lbs) front and rear, with narrow superlite 4s. I'm sure the 11.75" stuff could be plenty for single races, but bigger brakes last quite a bit longer. The 11x1.25 straight veined stuff is $45 each and 8.8 lbs but I'm sure won't last nearly as long as my bigger rotors. Back then I was also building the car thinking it would later compete in WRL GP1, and eventually GTO. Sadly the off the shelf kits that fit my 17x10 Konig Hypergram wheels were all 6-pot. So I had to spend more money to do 4s... I'd also look at Coleman rotor rings. They'll make you some in almost any size, and their curved vein stuff is IME a lot cheaper than the competition.
  8. We ran the cheapest RX8 rotors we could find for a while. They lasted ~2 race weekends and they're cheaper than replacement rings for a 2-piece setup. However if your rings are directional, as our Wilwoods now are, cooling will improve. Meaning they'll last longer. We've got idk 20 hours on our set of Wilwood fronts and there's not a heat crack in sight. So it's looking like they'll last longer. We don't run brake ducts, just removed dust shields. If you run ducts forcing air into the rotors I'd imagine directional veins provide less benefit.
  9. I'm not sure if you missed my point or disagreed with it, so I'll restate: IMO the primary things that make some ChampCars fast outliers do not and never have cost points. Just look at my NC as an example. So slowing the outliers down wouldn't be a matter of adding points as much as it'd be creating new categories (like tire compound and weight). Although the trouble with limiting tire width is that wider tires are actually cheaper to race on. See my post on the #225 SC300 above. The car went from 400 to 500 points and went faster. I'm pretty confident that if I bought it from David and did my best on it with 295 Coopers, we'd be < 2:30 at Sebring running 2 hours stints. Still at 500 points. I would benefit from the new brake rule, but not to the tune of a second per lap. Free stuff does not speed up the outliers unless its power or weight related. They already have the spring rates and shock valving they need. They probably already cheated on flywheels. Stock radiators work fine. They don't care about oil temps. The #225 car had to remove its cooler, and would wrap the oil temp gauge around itself. It probably made a bit more power like this because the oil, even the 60-weight 300V they ran, was thinner like this. Edit: I do agree 'free stuff' will in some cases speed up an outlier. We'd benefit from free spring rates because I can't be bothered to make custom or cut lowering springs work. I just don't think its more than 10% of speed creep.
  10. This is a good data point, but it can't be contributing to speed creep. Any car drafting someone else for multiple laps is not one of the fast outliers. We run the stock radiator with good ducting, some inlet restriction, and no fan. At 162whp the highest temps we've seen is 190F. A windshielded car which can vent its hood should be able to do better. Good ducting and venting is key to reducing front end lift and drag.
  11. In 2021, A052s. RS4s or RS3s have been available for many years, and are functionally very similar. But availability doesn't matter so much as what teams are actually running. I can only recall seeing A052s at a single Champ race. They are very expensive and short-lived. I can't speak to your particular circumstance, but I can speak for the September Sebring races. Sebring is a good way to look at speed creep because the track is so wide and passing is so easy. On a flow track like Road Atlanta FTDs will increase just because the rest of the field is getting quicker. We won this race twice in our old Z32, and my friend David Tenney won it five times in his SC300, with co-drivers Lee Saunders, Kevin Smith and once Randy Pobst. Starting in 2014, Sebring FTDs were: 2:32.4, 2:31.3, 2:35.5, 2:33.4, 2:32.1, 2:34.1, 2:30.0 (there hasn't been a 2021 race yet) You might point at 2020 and call that speed creep, but it was done by MK Motorsports, a powerful mustang which is highly fuel-limited. They finished on the same lap as one of Sahlen's Boxsters which had only turned a 2:32.6. So while MK turned very fast laps, I don't think this counts as speed creep. Notably, my friends #225 SC300 was almost completely unchanged from year to year. At one point it got a megasquirt, which improved fuel mileage. It overheated and warped the head once, so they shaved it. It started out with headers, an oil cooler, and a few other things when the car was 400 points, but those went away when VPI was increased to 500. With its normal drivers its fastest times ranged from 2:35-36s, but in 2017 Randy Pobst got in it and did a 2:33.4 (FTD for that year). This was not a fluke, as Randy ran multiple 2:33s and his ideal was 2 seconds faster than prior years (I have all the daq from these races). The #225 car had a lot left in it. The suspension was very soft and it was only on a 255 tire. However David wasn't interested in developing it, reasoning it kept winning anyway. It had picked up 2-3 seconds with driving improvements. It could have picked up more with suspension improvements and wider, stickier tires. Despite its VPI increasing and despite removing parts from the car, the SC300 didn't get any slower, and in fact could have gone faster at 500 points than it had at 400. So while I don't see clear evidence of speed creep at Sebring, the potential was certainly there. But it would not come from anything to do with points.
  12. For those concerned with speed creep I've got bad news for you: it's only going to get worse. Freezing the current rules won't help, because IMO most cars and drivers have many seconds left in them. Think about all the time you have left on the table vs. a pro driver in your car. Then think about all the aerodynamic components you could make with repurposed material, all the porting you could do, how much weight you could remove, etc. The ruleset makes optimizing a ChampCar very difficult, so it's taking people a while to figure out how. The result (plus driving improvements) is consistent speed creep. Slower cars tend to have their VPI reduced, which does help them. But this does not help the faster cars who tend to have their VPI increased. Some freebies like flywheels or whatever do help free up points, but not to the tune of seconds a lap. Aero can help quite a bit, but it's probably under-valued in the current rules.
  13. What FTDing cars run an aluminum radiator? Why would they? I'm sorry but 3.5 seconds a lap is not due to say 20 points getting freed up. That's driving improvements, tires, weight reduction, tires, and miscellaneous freebies (like porting, repurposed parts for aero, etc.). I'd wager it's mostly driving and tires. I benefit from softer tires more than anyone. At 1950# full of gas on 255/40-17s, I can run harder on stickier tires than probably any other car in the series. It's a big advantage. If you're running a 205 width tire, you're at a big disadvantage.
  14. What's wrong with speed creep? If the rules are changed so the back-markers improve, you get speed creep. And closer racing. The same goes for people just improving their driving, which is bound to happen. Most teams would be best off spending their time and money on practice, driver training, weight reduction, and hammering out their wheel wells to fit the absolute widest possible tires. The only way free parts have helped me in the past 10 years is lighter brakes, and again this is coming from having been involved in two cars which had FTD everywhere. I'd say flywheels will help too, but in my experience most people with lightweight flywheels didn't claim them at tech... The "free stuff" that could legitimately make me significantly faster is free fuel capacity, free power, and free aero. However we now have a total capacity fuel rule, and ballooning tanks is now illegal. In this respect the rules have slowed us down.
  15. I agree. They focus on things that don't affect speed and ignore two of the biggest factors that do: tires and weight. WRL rules aren't perfect either though. An E30 is going to be competing against other, better chasses with the same weight / power. You can't relocate a suspension mounting point (a must on a strut car) without a significant penalty. I hope they eventually get around to giving cars with poorer suspension geometry some help. ChampCar at least tacitly admits that yes, Miatas handle better than E30s.
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