Category Archives: Motorsports

Extended wheel studs for the 1988 Fiero

With aftermarket wheels and/or thicker brake rotors, the Fiero’s stock wheel studs don’t provide much thread engagement with the lug nuts. I found that on the front of my ’88 Fiero I was only getting 8 turns with the C4 12″ rotors and my Motegi wheels. That’s 12 mm of thread engagement on a 12mm stud. Marginal at best. With the 3mm spacers I wanted to add behind my rotors to get some control arm clearance, I would be down to a dangerous 6 turns or 9mm.

I scoured the ARP and Dorman catalogs to find a good candidate. The 1988 front hub holes are about 0.490″ with the stock studs removed. Dorman recommends a hole size between 0.017″ and 0.027″ under the knurl OD, while ARP recommends 0.005″ for iron and steel hugs and 0.007″ for aluminum. It’s not clear why there’s such a big range or difference between the recommended interference.

The closest longer studs that would fit are ARP 100-7708 and Dorman 610-323. The ARP 100-7708 studs have an 0.509″ knurl,  making a 1/2″ reamer the closest common size to the correct hole size (0.504″ by ARP’s recommendation). When installed, these studs increase the thread length by 0.84″ (21.4mm) over the stock studs.

The Dorman 610-323 studs have a 12.80 mm (0.504″) knurl, which fit in the original hub holes based on Dorman’s specifications. They are 54 mm long, thus increasing the thread length by 12mm over the stock studs.

I pressed the lug studs out of a brand new Rodney Dickman 88 front hub and measured the hole size as about 0.490″ at the smallest and around 0.50″ at the largest. I went ahead and pressed the ARP studs in without reaming the hole to 0.503″,  and they pressed in without too much trouble. The hub didn’t split, but a few metal shavings were produced by the knurl pushing through the hole. This fit exceeds the ARP recommendation for the interference fit, but is within spec if Dorman’s recommendation is followed.

1988 Fiero hub with ARP 100-7708 studs installed
1988 Fiero hub with ARP 100-7708 studs installed

Since these studs are so much longer than stock, open-ended lug nuts must be used. For GM wheels the stock ones should work. In the aftermarket, I found some inexpensive Gorilla lug nuts on The part number is 20033SD for a set of 20 lug nuts and the spline drive socket. These nuts are narrow enough to fit in aftermarket wheels. I tried some White Knight lug nuts but they were too large in diameter to fit in the lug but counterbores in my wheels.

I purchased these inexpensive Gorilla brand  open-end lug nuts on
I purchased these inexpensive Gorilla brand open-end lug nuts on p/n 20033SD

The Gorilla lug nuts fit perfectly in my aftermarket Motegi MR116 wheels. The only disadvantage of these nuts is that the require the use of Gorilla’s spline drive key. Some hex drive lug nuts are available from Vorshlag that look like they might fit, since they are small enough to use a 17mm hex instead of the 19mm hex on the White Knight lug nuts that were too large for my wheels.

After installing the extended studs and open-ended lug nuts, I had plenty of thread engagement while running a 3mm rotor spacer
After installing the extended studs and open-ended lug nuts, I had plenty of thread engagement while running a 3mm rotor spacer

The same studs will work just as well on the rear bearings as on the front.

2014 Porterfield RallyCross Season Opener

On March 16th 2014, a field of 83 drivers slid their cars around Glen Helen Raceway’s dirt course for the 2014 Porterfield Glen Helen RallyCross #1, the first event of the year.

The massive turnout brought an incredible variety of vehicles out to the race including Mazda Miatas, BMWs, VWs, a Dodge Neon, and others, with 50% of the grid consisting solely of Subarus.

Danny Downey (1992 Dodge Stealth #711) started the season with a Stock 2WD class win, leading by 13 seconds over John Black (2012 Ford #34) ), with Matt Price (2013 Ford Focus #39) close behind. With with Downey’s previous rival Bill Martin — the 2013 Championship winner for Stock 2WD — having moved to Stock AWD class this year in a new car, Downey doesn’t yet have a close rival in this year’s championship.

Stock AWD class saw a very close finish between rivals James Veatch (1997 Subaru Impreza #155) and Mathew Mendoza (2004 Subaru WRX #420) with only 0.416 seconds separating the two but Veatch coming out ahead — that’s a mere 0.1% difference in total times! Bill Martin finished 6 seconds behind the win, but expect to see him remain a contender for the rest of the season.

Prepared 2WD saw a grid of 3 drivers, with Sarkis Mazmanian (1993 Honda Civic #777) and Vahan Yessayan (1988 Toyota Corolla FX #160) in a close battle for the lead. Mazmanian finished 0.541 seconds ahead of Yessayan — another surprisingly close race that mimicked what happened in Stock AWD. It’s looking to be a good year!

Brent Smith took the Prepared AWD class lead in his 2009 Subaru STI  (#433) with the fastest total time of the day and 7.3 seconds over Daryl Fike’s 2005 Subaru STI #16.

Modified 2WD saw the largest grid of cars with a total of 20 entries. Eric Martin took the lead in his 1982 VW Rabbit (#4) with a 5.41 second lead over Michael Cadwell’s 1994 BMW 325is (#854). David Moss (2010 Ford Focus #22) finished in 3rd, 4.93 seconds behind Cadwell’s BMW.

The flagship Modified AWD class saw 18 total entries and some close finishes. Cameron Meng (2006 Subaru WRX #511) took the class lead, followed by Mark Ackenback’s 2004 Subaru STI (#733) and Thomas Bloess’ 2008 Subaru WRX (#31).

And  now.. on to the pictures!


Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

(c) Copyright 2014, Steven T. Snyder, All Rights Reserved.

A Mean Blue S2000 at Speed Ventures February 15, 2014

To get warmed up for this year’s season of NASA track days, I signed up for a Speed Ventures autocross at Auto Club Speedway in Fontana, California.

Speed Ventures hosts the autocross event on one of the infield parking lots at the same time as a track day event on the Roval course, a demanding circuit with a mix of high-speed banked sections on the NASCAR oval mixed with a more technical infield course.

In between my autocross run groups I took the opportunity for an impromptu photo shoot – including some on track action – with Chris’ Wiita’s awesome 2007 Honda S2000 AP2.

Chris Wiita was there for the Speed Ventures track day with his Laguna Blue Pearl S2000, which he’s been modifying and tuning since purchasing it in 2010, when it was bone stock. Chris started by dialing in the car for autocross and moved on to track days in 2013, where he’s been setting highly respectable lap times at various California road courses, including a 1:58 on the Roval with street tires. You can see a video of that run here.

Laguna Blue Pearl is probably the best color this car was ever available with, if not the best Honda color ever!
Sparco Rev seats and blue Schroth harnesses adorn the interior. A Hard Dog Fabrication roll bar anchors the harnesses, provides rollover protection, and a place to mount a GoPro!
As clean and sharp looking as this car is, the mods are pretty much all business.
The APR-250 wing is supported by custom aluminum uprights that Chris designed and built. The uprights are skeletonized to reduce weight but the holes are covered with composite panels to reduce drag.
Chris set a 1:58 lap time on 255/40/17 Hankook RS3s
Hawk HP+ pads slow this AP2 down lap after lap without fade, but once this car gets an upgrade in the power department, a big brake kit will probably make an appearance. Knowing Chris it will be something we haven’t seen before on an S2k.
The custom water-jet cut and machined aluminum wing risers attach to steel brackets connected directly to the frame to transfer maximum downforce to the rear tires.
Stack oil temperature and pressure gauges give Chris a clear indication of how the engine is dealing with being pushed hard on the track.
Chris’ S2000 currently sits on Enkei PF01s wrapped in 255-40-17 Hankook RS3s, but he tells me that big upgrades in the wheel and tire department are on the way.
The massive APR GT-250 wing really dominates the appearance of this S2000 on the track. It looks wider than the car!
Chris records all of his laps on multiple GoPro cameras to review and share at te end of the day.
The carbon fiber wingstand brace and plastic airfoil really show Chris’ attention to detail. This Honda S2000 has a lot of interesting modifications that aren’t seen anywhere else.


2013 Porterfield Glen Helen RallyCross Finale

Last Sunday was the final race of the 2013 Porterfield RallyCross Series at Glen Helen Raceway. I showed with and competed in my Apocalypse Wagon, scored enough points to hold my lead, and won the 2013 season! The rest of the day was spent shooting thousands (THOUSANDS) of photos of the highly-entertaining afternoon run groups.

Here are some of my favorites. I shot these photos using my new Canon 70D with the EF-S 55-250mm f/4-5.6 IS STM lens. I try to minimize post-processing. Usually just a bit of contrast and exposure adjustment.

Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

(c) Copyright 2013, Steven T. Snyder, All Rights Reserved.