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So yeah what a shock i would think of his. Well after my little foray into the wall I decided I might just make this a serious track car. So I was looking at what I have invested and what I need to add. So here is another opinion. I'm not looking a building an enduro car but I know where these cars are strong and week. I don't know you class rules so these are just ideas.

1. Find a used 02-03 Z06 for as close to $20K as possible. 50K miles or so is insignificant. As close to stock as possible.

2. Get 2 sets of used CCW wheels. 12x18 and 11x18 is 1 set. Used is bout $2,500 or maybe $2,000 if you're lucky.

3. If you want to run the whole race on one set of tires then Hoosier VRLs might work. I ran the hell out of them and they won't die. But the grip does fall off predictably. If not then I would do 2 sets o R6s. If you are gutsy and do a 3 stopper and can get tires mounted there. Bring a 3rd set of Hoosier A6s that have on decent heat cycle. Use them to qualify. Regardless of the noise of them being an AX tire. If you are running in the late fall or early spring. They outrun R6s everytime. Ask any T1 racer. So rubber costs are about $1,400 / set. That is 2 - 335/30-18 + 2 315/30-18. I prefer staggered but some like 315 square. I think the car is too tail happy.

4. If you can pull the stock shocks, springs, bars, end-links. You can sell them used easily. If you want to play deep pockets call Gary at Hardbar and go with his Penske double coil-over set. I think they are too pricey. $5,000. I'm running Pfadt coilovers and like them. $1,500 when I got them. Closer to $2,000 now. Full ride height independent of shock travel. He sells several spring sets so you can tune. Shocks have 15 adjustments. My car is ride height set and corner weighted.

5. Go to Pfadt and get their adjustable sway bars and end links. About $1,000.

6. Go to Gary at Hardbar or Pfadt and get poly or sperical bushings for control arms front and rear. $300-$500. Oh throw in a camber a kit for about $300 or so. You can get past 2deg and closer to 4deg I believe.

7. Go to DRM, or LGM, get a big radiator and lay it back. Also get an external oil cooler. The integrated ones do not work as well. I run an external unit from DRM. It's a Setrab cooler. Workds excellent. $650.

8. Go to DRM, LGM, get a trans and diff cooler. You stick each cooler in the rear brake duct opening. LGM makes a really nice setup. $2,000.

9. Replace the valve springs with better quality ones. About $300. Stockers are are ok to 6400rpm. You can tune the motor to 6800rpm with better springs. Safely.

10. Any CAI to open up breathing. Any good headers with high flow cats. That's about $2,000. Leave the Titanium exhaust alone. it's good to easily 500hp and light as a feather.

11. Brakes. You ain't lasting 13 hours on the stockers. Get some Stoptech, Brembo, etc... Plan on $5,000. 6 pot fronts and 4 pot rears. Make sure they will clear the CCWs. The much fatter pads you can use might make it. If not you can change fronts in 1 minute. Rears should last.
Along that lines you need brake ducts all the way into the spindles. You would really want custom Coleman rotors. They would last. I know one place that builds them. They ain't cheap.

12. Safety. 6-point bar or full cage. Go see Joe at Phoenix or MTI down in Atlanta. Could even talk Dave Farmer into building one.

13. Aero, See Keri Hit. He does all the ACI stuff and built the WC bodies and some other very nice work in fiberglass and carbon fiber.

14. If you can get into the top end of the motor then LGM has a nice road race kit. comes with the right springs, cam, and setup and tuned. Get you closer to 400 to the wheels. Getting 500 to the wheels may take a visit to Kartec or P&M.

Do not let anyone talk you into as SC or TC motors. These cars run too damn hot in a 30 minute session. An SC in a 13hr enduro. I think would make a really cool grenade... Just my opinion. Build an NA motor only. I'm just waiting to see how many ZR1s blow up on track.

There is more. That's just off the top of my head. I thought about dumping my C5 Z06 and getting a C6 Z06. But I have other ideas now.

Watching out for you front brakes in these cars is a big deal. You'll trash the pads and rotors in no time if you don't manage braking.

At VIR Full. I have about 8 weekends on it now. In my Silver Z06 I average 2:14s for a 20 minute session, with passenger, on old Nitto R2 and Carbotech XP8s. 2:12s on my own. That was my 6th visit. With Hoosiers on the Blue Z06 and the bars shocks adjusted right I can run 2:10. That was 8th visit. Not used to the grading thing they did to the tar. I'm not a racer, just a hack. I'm shooting for 2:08 next year. Other than coilovers and bars my car is stock 02 Z06 with 50K miles on it.

If your team has any talent you can run 2:10s all day. Preserve brakes and tires. Push 2:08s when you need to catch up. If you can do a 2:06 or lower I want the data logs from that session

I think we're talking $50K but that means you and your buddies get dirty and do some work. The cage, press fitting bushings, alignment, height and weight setup you might need help. They are not that hard to take apart and setup. I did mine on my garage floor on jack stands and rhino ramps.

Just a thought on building something other than another damned bimmer... good luck whatever you pick.

Graham

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Okay, so we've tried to boil things down to a list of what we'd really like to have in a race car:

. 2:05 capable FLAT OUT with GREAT driver (so we can run 2:10-2:12 in traffic)
. not (and never was) a convertible
. production based
. no fiberglass bodies
. RWD
. double wishbone
. good fuel mileage
. ability to mount a 25 gallon cell safely
. must be able to fit a 6'5" driver

There aren't a ton of cars that fit ALL that. That's what we'd LIKE to have, though, and some are flexible (like the double wishbone thing). But so far the closest we've found is an Acura NSX. So that's what I'm investigating right now. The Vette doesn't do well in the MPG category nor the fiberglass bodywork thing. The BMW is closer at really only not fitting the double wishbone thing, but when you factor in bang for the buck, the Acura might be cheaper. The big question is fitting the tall driver, but we think as a gutted race car we'll be able to handle that.

We think with the weight distro, overall weight, tire package, and HP we can get should get us in the 2:05 territory no problem. We were at a 2:09 in a FWD with bad weight distro and less tire and way less HP. We'd have 60 more HP, weight in the rear, bigger tire in the rear to match, and the same weight. And a better suspension to begin with. Plus we should be able to do better aero with off-the-shelf stuff. Lower Cg, lower Cda, same exact weight. The reliability problems have all pointed to FWD kind of issues to me with our previous Acura (the axle and the steering could both be load issues thanks to the front wheels trying to steer and drive at the same time).

Anyone see any holes in this one? With prices coming down a lot on used NSX's, the things are seeing a resurgence as a track day and race car, it would seem. Good used cars can be found under $25k. Yeah, that's a lot less than an E36 donor car would be, but we won't need to spend near as much on it to get it to that 2:05 as we would an E36, either.


--Donnie

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what kind of lap times can a prepped RX8 turn?

Oh yeah, that gas milage thing...

still leaves a 911 GT of some sort too.

I really think by the time you get the power out of a NSX, you gas mileage will be about the same as an LS2 V8.

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Marty Howard
2011 NASA SE Factory Five Challenge Champion
Track Events Logistics Coordinator - TZC/THSCC
2007 Factory Five Challenge Car.
http://www.mh-motorsports.com

911's are out on the cost thing. Besides, I'd build a Cayman before I'd build a 911 given the power levels we're talking about. Cheaper late model donors, better balance, can put all the good 911 parts on them anyway.

Should have put in my list of requirements:

. piston engine

Rotary engines need not apply for mileage AND longevity reasons. It's been proven they CAN run for long periods, but it's a bitch to do it.


--Donnie

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a nsx doesn't need to make that much power to be fast. i turned a 2:17 in my 100% steet legal nsx on azenis and smallish stock brakes, full interior with a/c and stereo. lose the cats and a couple hundred pounds, add race tires and brakes, put a good driver behind the wheel and 2:05 should be within reach.

Oh yeah, just to update this, 300HP out of an NSX is pretty easy, in fact. Normally aspirated. They can be pushed in NA form far past that, but the bad things start happening there. But 300 is fairly conservative and should leave us some room to tune for mileage.

I'm likely to use an earlier body (to get the coupe...the later ones are all targas) along with the later motor (a 3.2L instead of the 3.0) and a later tranny (6sp versus 5sp, and the 6sp has better gearing).


--Donnie

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Is finding and preparing an NSX really going to be less expensive than doing so with a 911?

Obviously, I've never researched the two personally. It just seems to me that there are the knowledge, and the parts, easily accessible to make a 911 go, turn, stop, and last however you want it to. I'm a little less sure such stuff exists for an NSX. Maybe it does, but I'm confident that on "strength in numbers," a 911 is going to win.

Now, if you just don't "want" a 911, that's fair enough.

There's also the whole crash repair thing. With much of the NSX being made of aluminum, is it going to be fixable after an impact? If it's fixable, is it going to cost a fortune to do so?

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Karl S.
2014 Baby, 2014 House, 2013 Ford Focus ST, 2013 BMW 328i, 1994 Mercedes E320
(Insert passive aggressive signature line here)

You've obviously never had to buy Porsche parts. All I can say is I've had to buy both Porsche and Acura parts. Many of both. There is no comparison.

Seriously, to build a car for something like the VIR 13, you'd really just have to "want" to build a 911 for it to make any sense at all. You'd have near twice as much into it (if we're talking apples to apples and doing it "right"...you can certainly build a "budget" 911, but that's not what we're after here) and you'd be paying more than that per year in maintenance and repairs. Easily.

Why do you think the 911 guys get so bent when we show up at PCA DE's and whip their butts with a Spec Miata?


--Donnie

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Do NSX parts have similar pricing to RSX parts? I'm not trying to be argumentative, I'm just asking. The RSX was a mass market car, and the NSX was built in small numbers, mostly by hand. If NSX parts are also much less expensive than Porsche parts, great. Sounds like you may have found your target car after all.

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Karl S.
2014 Baby, 2014 House, 2013 Ford Focus ST, 2013 BMW 328i, 1994 Mercedes E320
(Insert passive aggressive signature line here)

It's something to check into, but I'm doubting they'll be significantly different. Remember that our RSX had a lot of unobtanium JDM stuff on it as it was. Stuff we had to wait MONTHS for. Since the NSX didn't have any kind of uber-model in Japan we shouldn't have to worry about that kind of crap.


--Donnie

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also, some parts are common with other honda models. for example, my car had a slightly wonky speed sensor that i was reluctant to replace since it was $125. but further research showed that a $25 honda accord sensor was identical.

Jason Tower would probably know better than I do, but I'm almost positive there was an NSX Type R in Japan. There was also the Zanardi Edition NSX. with thinner window glass and all sorts of other lighweighting measures. So if you care about special edition stuff like that, I'm pretty sure those two cars exist.

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Karl S.
2014 Baby, 2014 House, 2013 Ford Focus ST, 2013 BMW 328i, 1994 Mercedes E320
(Insert passive aggressive signature line here)

true but for the most part they weren't anything extraordinary, the parts that were different would likely end up being removed (glass, interior trim) or replaced (spoilers, suspension bits, brake pads) for serious track duty anyway.

Yeah, I should clarify. There was no uber-model that was WAY better than what we got in the US. Unlike most of the econoboxes. And the RSX is just an upmarket econobox.

The Zanardi is what you'd want if the NSX was something you're gonna stock class autocross, but there's nothing about it we wouldn't change on a real race car.

The big thing here is that the suspension is already double wishbone. A lot of the JDM specific stuff is suspension bits to make the strut system racier. Things like LCAs so you can actually lower the car without shit hitting. No such problems with wishbone systems (one of the reasons I want to go to that, the other being struts wear out faster than shocks, and that's a big deal when you're talking 13 hour racing).


--Donnie

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