TEIN Suspension Upgrades & More - Project S13

Looking for a more precise alignment, we sourced a set of adjustable rear arms from SPC Performance. Manufactured out of steel tube with full adjustability, the SPC arms are vastly stronger and resist flexing when compared to the cheap stamped steel stock arms. The arms also come fit with new rubber bushings, which are a higher durometer than stock. SPC sells three links for the rear, a camber link, toe link, and traction link, of which the latter can be used to adjust for bumpsteer. To start, we set all the arms to stock length and then adjusted them for our alignment settings.

SPC Performance's rear control arms swap out three links per rear corner to adjust toe (top), camber (middle) and bumpsteer (bottom). Stiffer than stock rubber bushings are pre-pressed into the arms and there's no deformation like with the stamped steel stock arms.
SPC Performance's rear control arms swap out three links per rear corner to adjust toe (to
Adding more camber adjustment range to the front upper plates, M1 Fabrication & Development machined the slots to allow the struts to slide further in. Notice the small pocket that has also been machined into the lower bearing plate. This is done to provide clearance for the inner mounting stud's head, which protrudes out the backside of the green plate.
Adding more camber adjustment range to the front upper plates, M1 Fabrication & Developmen

To go fast, we're talking Corvette and Porsche-beating fast, Project S13 would need a lot of camber. Strut-type front suspensions like to have large amounts of static camber, on account of their horrible camber curves. Thanks to the SPC arms, Project S13 wound up with nearly 3-degrees of negative camber and 1/16-inch total toe-in in the rear. In the front, we got a measly 2-degrees of negative camber. Not good enough. With our non-refundable registration fees already on the line for a Buttonwillow test day, we headed over to M1 Fabrication & Development with just two days to spare.

When's he not working on 250cc Superkarts from the likes of Wayne Rainey (three time 500cc World Championship motorcycle champ) and Eddie Lawson (four time 500cc World Championship champ), M1's Mack Sunthonlap applies his sizeable fabrication knowledge to 19 year-old derelict projects from SCC. Yeah, we're not sure how we pulled that one off either.

Project S13's camber limitations were being caused by contact between the strut tower's support ring and the heads of the camber plates' inner bolts. Sunthonlap machined out the TEIN upper camber plates to allow more adjustment range and then drilled a set of holes in the top of each tower to provide clearance for the camber plates' bolts. A pair of chromoly rings were then cut and welded into each tower to provide structural support and our "Mickey Mouse" strut tower tops were done. 3.5-degrees negative camber each side without breaking a sweat.

Even with the older Type HE's camber plates, the limiting factor for the front camber adjustment is contact between the strut tower's support ring and the inner adjustment bolt heads. We didn't feel safe sliding the plate all the way in and only running two adjustment bolts.
Even with the older Type HE's camber plates, the limiting factor for the front camber adju
Two chromoly rings, per side, were cut to reinforce the main strut tower support ring.
After drilling two holes for camber plate clearance, the chromoly rings are welded into place and ground down to fit.
After drilling two holes for camber plate clearance, the chromoly rings are welded into pl

With the car buttoned up, we headed out to Buttonwillow Raceway for a shakedown test. Once on track, Project S13 violently and quickly snap oversteered the instant it touched its first bit of curbing. The car became nervous, wandering over any surface that wasn't as smooth as glass and lacked any and all feedback during cornering.

When we returned, we discovered play between the front lower control arm and spindle. We had the wrong balljoints installed. Project S13's previous owner had recollected that the 5-lug hub conversion was done using conversion hubs only. Wrong. We discovered earlier during the coilover install that we had S14 front spindles but neglected to follow up on it. We soon found that Project S13 used S14 spindles, hubs, balljoints, and S13 lower control arms for the front 5-lug conversion. Stupid us. We had earlier sourced an S13-application Megan Racing roll center kit, which has a different taper on the balljoint than the S14 kit and won't seat correctly. We've since swapped the front for a Megan Racing S14 application roll center kit. If you're carrying out a 5-lug hub conversion, do not attempt to use S14 spindles and S13 balljoints. Learn from our mistakes. First lesson - keeping control arms attached to a car is a good thing.Previous installment

Previous Installment

January 2008

Part 1: Getting ambitious

The end result is 3.5-degrees of negative camber up front with clearance for the camber adjustment bolts. Now the limiting factor is the strut's upper mounting nut.
The end result is 3.5-degrees of negative camber up front with clearance for the camber ad
Coming up - Nismo reinforced six-speed transmission. Stronger than a S15 six-speed, lighter than the stock five-speed, and a direct bolt-in for S13, S14, and S15 models.
Coming up - Nismo reinforced six-speed transmission. Stronger than a S15 six-speed, lighte
Megan Racing S13 front roll center kit (L) and S14 front balljoint (R). Notice how the tapers on the shank are different? We didn't, not right away, and almost paid the price with a non-seated spindle. We've since switched to a Megan Racing S14 front roll center kit, with the correct balljoint taper, to match our Megan S13 rear roll center kit.
Megan Racing S13 front roll center kit (L) and S14 front balljoint (R). Notice how the tap

SOURCEBOX
K&N Engineering 1455 Citrus Ave. Riverside CA 92502 800-858-3333 www.knfilters.com	Megan Racing
Radiator diversion panel	US Composites Chassis
JDM Power 949-855-9174 www.jdm-power.com	M1 Fabrication & Development
Tein N/A www.tein.com	SR Motorcars 310-516-1003 www.srmotorcars.com
SPC Performance www.spcperformance.com	Mavrik Motorsports 714-523-1896 www.mavrikmotorsports.com
Energy Suspension 1131 Via Callejon San Clemente CA 92673	Tokyo Auto Repair 714-993-7300