The club with which I autocross starts the 2014 schedule on January 26th; so I’ve been getting the Crossfire ready. Thanks to the Solo Events Board’s rational decision, the NA Crossfire remains in D Stock for 2014. As most of you who autocross probably know, there are now two stock classes in SCCA events. The new class, which uses street tires (140 wear rating for 2014 and 200 wear rating for 2015), is termed “Street.” The old stock class, which allows race tires, is now “Street R.” An interesting rule change in Street class allows a one inch deviation from stock in rim/tire diameter, but there is no change in rim width allowed. So I decided to go with 17 inch front rims and 18 inch rear rims, hoping to lose some weight and mount a wider tire than stock. I chose to purchase two Sparco Assetto Gara 17x7.5 for the front, mounting 245/40/17 B.F. Goodrich Rivals (200 wear rated). The Sparco’s weigh 18.7 pounds versus the stock 24.5 pound rims. For the rear, I chose OE Wheels LLC replica Mercedes 18x9 rims (about 28 pounds) that were on clearance for $53 each. On them, I mounted 275/40/18 Nitto NT-05 (200 wear rated). I chose the 200 wear rating so that I could use them in 2015 as well (assuming that they’ll last two seasons).
Additional modifications to the 2005 Base Coupe had included a cat-back exhaust, 30 mm H&R front sway bar, K&N filter, and Koni yellows on all four corners. I haven’t had a chance to try the new tires yet, but I’m expecting considerable improvement over the stock sized Michelin Pilot Super Sports, on which I autocrossed last year.
I’ll let you know how the car works after the autocross on the 26th. Then I’ve scheduled a mini race school at Harris Hill Raceway in San Marcos for February 7th. Then on February 23rd, I’m driving an Audi R8 for three laps on Harris Hill Raceway, courtesy of my younger son’s Christmas present. I feel blessed!

 

I need to talk to my sons.... Sounds like fun. I have an interest in putting the roadster out there for some fun. I belong to SCCA, but have never really done anything with them yet...probably about time to use those dues paid...lol Have fun, stay safe...give us a report on the R8. I have been in a few exotics, but not an R8

 

Good luck and have fun! I see more Trophy's coming.

Les

 

Keep us updated on the 17's up front, we're a little worried that wouldn't let as much heat out from the brakes and cause even more brake fade with 2 drivers. How is the clearance with the 245/40? Any issue with the top nut? Have you fitted the rears? I wouldn't have guessed the 40 ratio would fir but if so wow, there's more room then I thought
Good luck this year to all you autocross guys, stay safe

 

An autocross run isn't long enough to overheat the brakes IMO. I'm curious about the clearance with the calipers though.

Les

 

The clearance of the 245/40/17 is about 4mm between the tire and top nut. I'll check them during the first autocross and insert a 3-5mm spacer if needed. The rims are 35mm offset. In the rear, there's plenty of room for the 275/40/18. The rims are 32mm offset; so I used a 10mm spacer to bring them out to stock (22mm). Here are the pics.

 

Caliper clearance is not a problem at all. Plenty of room front and rear.
Stefan

 

You say that but trust me it can happen, haven't done it lately with upgraded pads but we have noticed fade with 2 drivers with about 10 minutes of cool down in between laps

 

I haven't noticed any fade since upgrading to metal lines, high performance brake fluid, and the ceramic pads. I could heat them up before that...

 

I didn't know about 2 drivers with almost back to back runs. Under those circumstances I'm not surprised. I'm excited to have another autocross'er in our ranks. Go Shaag! Go Shaag Go Shaag!

Les

 

I am looking forward to hearing your review of the tires. I will need to buy new tires this year and will get 200 treadwear tires for the same reason you did. I have been looking at the BFG Rivals and the Dunlop ZIIs as the top two choices.

 

I'll post my review after the autocross on January 26th. Let's hope that the weather cooperates and it's not cold in San Antonio. BTW, I've decided to put 5mm spacers on the front to increase the clearance with the upper control arm nut. I have the Nittos on the car now to see how they do. I'm liking the slightly taller tire and the 200 wear rating--more first gear and higher speed in second.

 

I'm surprised you went with a bigger bar in the front. Oversteer is rarely an issue with these cars.

 

You need to drive my car then. It oversteers on turn in under trail braking, (badly so I don't do it) power on oversteer (controllable) and high speed corner oversteer. (slight but scary) My rear sway bar is more or less disconnected to deal with it.

Les

 

I have been following the build that is in this thread:
https://www.crossfireforum.org/forum...-build-ds.html
Last year, using the H&R 30mm front bar, my times improved quite a bit. I attribute the improvement to the bar. We'll see how the wider BFGs and the big front bar get along on the 26th. I'm optimistic.
Stefan

 

Les send me all your set up stuff you have, caster, camber, toe, rake, tires and sizes. Your car should not be that loose, your rake might need to be changed. Off the top of my head without seeing numbers I would say you need to lower the rear of your car alittle. Rake is super important in the overall set up.

 

Front: camber -3º caster 5.2 toe 0 rake is 1/8" (can't go any lower with the dive under braking without rubbing the inside of the fender well) 245/35/18 on 18x9
Rear camber -1.7º 1/4 toe in 275/35/18 on 18x10 New front shocks on full hard. Rear shocks at 4 clicks (soft) Rear sway bar is set real loose with adjustable links. Car weights 3300 lbs with me seated in the car with 1/2 tank of gas. The rear of the car will come around under heavy trail braking so I brake early and am on the gas just before the apex. The only times I've gotten a push is on the gas coming off slow or medium speed corners. I can lower the rear easily but the front can't go any lower until I have less dive, squat and roll.

Les

 

Bring the front up or the rear down. Also if you are running that much camber in the front you may need more camber in the rear, try for -2.5 if you can get it. Everything else looks pretty decent. Your toe is in the rear may be a little aggressive. We run 3/16 toe out in the front and 1/8 toe in on the rear.

 

I'll remove some of the rear toe and increase the negative camber in the rear and see what happens. I increased the negative camber up front when I switched to Hoosiers. The front wear looks good and the rears indicate I can run more negative in the rear. I don't want to hurt acceleration so I'll keep the rear camber as upright as possible. I'll try -2º. Of course, all my settings may change with the Ground Control suspension. With less dive, roll and squat I can lower the car more without creating contact with the inner fender wells.

Les

 

We solved our rubbing with a BFH....I'm guessing you are not going to be following suit lol.