Ben Diss

I stopped by Phoenix Performance in south eastern PA last week and got a good alignment. I brought along my camera so I thought I post the pics and explain what they did for everyone's enjoyment.



http://www.phoenixperformance.net/

Ben Diss

Step 1 is to get the car on the rack.

Ben Diss

Next the sway bars are disconnected.

Ben Diss

Before setting the ride height, they simulate a full tank by adding weight to one side. We have two tanks and when the car idles, one tank will end up holding most of the gas. Here, Brad checks the tank levels with a Tech 2. Interesting thing to note here is that on newer (maybe '06 and up) Vettes the excess gas is returned to the right tank while on prior years it was the left tank.

Ben Diss

Setting the ride height is an exact science. Some people do it them selves and measure from the some point on the chassis to the ground or from the fender above the wheel to the ground. Thats not how it's done. Take a look at the special tool needed to measure correctly.

Ben Diss

I wanted the car lowered as much as possible on the stock adjusters. I had already taken it down three full turns in the back and five in the front. We went down another turn in the front and then just evened everything up. That got us about 77mm rake. GM spec says 70mm is good and I was OK with a little extra.

Ben Diss

At this point we're about an hour into the job. The weight simulating the full tank of fuel is removed and the drivers weight is added to the seat and floor to begin the alignment.

Ben Diss

When it was done, Brad made a mark so that it would be easy to see if something moved later at the track.

Ben Diss

The alignment had been way off. Here's where we started:

LF camber: -0.76 toe: 0.10" caster: 8.78
RF camber: -1.24 toe: 0.10" caster: 8.48

LR camber: -0.20 toe: 0.09
RR camber: -0.60 toe: 0.05

We talked quite a bit about what I wanted and what I didn't want. I didn't want much if any additional tire wire. I did want better grip in the turns. Here's what we did:

LF camber: -1.25 toe: 0" caster: 7.70
RF camber: -1.25 toe: 0" caster: 8.30

LR camber: -1.00 toe: 0.03"
RR camber: -1.00 toe: 0.03"

Ben Diss

After the alignment was perfect, we moved on to corner weighting. This was optional and took the job from two hours to three, but I wanted to see what it was all about.





The corner weight is adjusted with the sway bars still disconnected, by adjusting the ride height slightly. To dial it in we only moved one corner by about 2-3mm.

Ben Diss

All that was left was to adjust the tire pressure, pay the bill and go for a ride.

Ben Diss

Two BIG things were improved with this alignment.

1. High speed stability feels much better. Spirited lane changes are more predicible and solid. Beginning the turn take less effort on the wheel.

2. Going over bumps in the highway with a side load used to be very exciting. The front would handle OK with the usual jerk of the wheel, but the back would go scooting off towards the outside of the turn. This wasn't oversteer. This was the rear end lifting up and stepping over a foot or so. It's completely gone now. The back follows the front around these turns perfectly.

The guys are Phoenix are top notch. I got much more attention to what I wanted than I expected. This is a race shop and I'm just about a poseur. They had four or five non-streetable Corvettes there. With the vert, I'm unlikely to ever run at Pocono or Lime Rock, but they took a lot of time to understand how I drive and what I was after. I think I just exactly what I asked for. It was well worth the 2.5 hour drive and 3 hours of shop time.

johnodrake

Nice write up Ben. If you don't mind sharing, what did they charge you?

drivinfast

Great write-up. I had made a lot of assumptions about what I did when I replaced the OEM lowering bolts with TKO's aftermarket bolts and why you need an alignment afterwards. At least I should have put a mark so I could return the cambers back to the mark, before I did the lower a arms. thanks

ben dover

Interesting - thanks.

Ben Diss

Mine was about $350, but then I got in the way a bit and slowed things down. I'd say expect to spend between $300-$400.

LS2-Zomb!e

Thanks

SMR 67

Nice writeup Ben. Sounds like a top-notch shop.

tdelena

I had my car corner-weighted and aligned too. I had the same requirements as you with better handling, but wanted even tire wear.

This is what we did. The car had a slight pull to the left and this is why the uneven caster. I had pretty even wear on the stock Supercars. Fronts had more wear on the outside 1/3 as opposed to the inside 1/3 and rears had more wear in the middle.

BEFORE:
LF camber: -0.5 toe: 0.05" caster: 7.7
RF camber: -0.5 toe: 0.04" caster: 7.5

LR camber: -0.80 toe: -0.03
RR camber: -0.40 toe: 0.07


AFTER:
LF camber: -0.75 toe: 0.02" caster: 8.1
RF camber: -0.75 toe: 0.02" caster: 8.7

LR camber: -0.50 toe: 0.05"
RR camber: -0.50 toe: 0.05"

I agree that the car is much more stable at highway speeds. High speed lane changes are GREAT fun. I also have the Koni FSDs which help with high speed stability too.

I wonder if my negative camber should have been a little more agressive? He said the toe in the rear is for better traction getting out of the hole.

Ben Diss

We talked about the rear toe as well for launch. I thought that a touch of negative toe in the rear helped with launch though, but now I can't remember for sure.