LVDell

Andy, I spoke to several people at length about this and then studied the suspension and then it make perfect sense to me. Now I know for sure what certain changes do to the settings and what choice I want to make. There is nothing wrong with changin caster. You just need to ask yourself what setting you are comfortable with and if you can live with what it produces.

DavidNR

Andy,

I had the struts rotated on my car and it did not change the caster at all. If all you need is to increase camber just rotate the struts. No additional parts needed.

I got this from this forum:

David

NJ-GT

1. Correct

2. Not quite. Take two stock camber plates (I have four of them, I don't know why), one with studs on the stock position and one with studs in the rotated position. Align both camber plates to the mounting position, there is only one way to get the three studs aligned to the slotted holes. You will notice that the rotated plate has the strut hole inward and a little bit forward (less caster).

I used to run toe-in at the front and still had a busy steering with the rotated plates (-2.5 camber, 0.10 toe-in per side). Today, I run -2.7 camber and 0.15 degrees toe-out per side with the Manthey plates, the car is pretty stable even under heavy braking. Caster sits at 9.2, it was at 7.8-8.1 with the rotated plates. I use 2mm of shims as well.

To save money, I would add shims (4mm) and extend the slotted holes. This gives you more caster (good for stability) and more camber (good for higher speeds through turns and wallet). With 7mm of shims, the stock tires/wheels rub the inner fender, with 11mm of shims you can't even turn the steering wheel.

You can still install ERP adjustable solid bushings and play with the caster at will, but fender liner rub has to be watched.

With the right combination of parts, I get to run 285 tires on 10" wheels.

boqueron

My Caster, AFTER rotating struts is at 8.32.

LVDell

I didn't lose caster settings from my new alignment. Just got it back from the shop and my camber "floor" was -2.59 and ceiling was about -4.0 and caster remained relatively the same.

multi21

I just flipped my Nittos on the rims because of excess wear on the outsides (I need more -camber). Has anyone else done this? Any change in handling that was noticable?

Rickard 993 Turbo

After reading this tread i think im rotating and use as much shims i can so i get maximum caster before rubbing the fender liners

fhp911

good news for LVDELL:

The extra weight you mention from the holidays is SPRING, not UNSPRUNG weight, so it isn't as bad.

Cheers!

LVDell

hehehe

blake

This thread is so good - I needed to revive it....

During my last corner balance & alignment (Aug 07), I went with the following:

Camber (F2.2/R2.0)
Toe (F .5mm OUT/R 1.0mm IN)
Ride Height (FL-115, FR-116; RL-128.5, RR-130.5)
Used 4mm and 2mm Shims rather than rotate...
CB Weights (FL-648, FR-635; RL-1068, RR-1047)

This was track specific per Synergy here at MMP in Utah....

My less aggressive alignment yielded 5 days out of my Cups, and this alignment corded the two right tires after 4 days...

Any ideas?

Thanks,
-Blake

LVDell

What was the previous setting? Where was the cording? Is the driver better?

BTW.....are you sure about those corner weights? 3398 is a heavy pig! Mine is 2993.9 (net) and 3227 with fuel (1/4 tank) and driver. And the ride height seems to have a much more pronounced rake.

blake

Ah Dell... If I only knew! The previous settings were set by the local dealer tech (Aug 2006), and he did not pass along the specs. I gave him the Kussumaul settings, and he then decided that they were too aggressive and chose a mid-point between stock and Kussumaul. For my next alignment (Aug 2007), I took it to Synergy's new operation in SLC....

The cording is on the outside of both right tires... The car feels a bit more balanced (horrible description, but all i can come up with), but the steering wheel shudders between 60-80mph and I think that is a tire balance issue. As I am always "high" on the sensation of actually driving on the track, I have learned to deal with the quirkiness of the car and find that to be the part of the fun...

Regarding the corner balancing, those are number that the Synergy guy wrote down on his report. I am learning that he may be a bit of a loose-cannon/roque employee, so will be looking elsewhere for service this coming year... Long story on that front. I am scheduled for an alginment/CB in a few weeks with a local race shop, so will keep you guys posted...

-Blake

LVDell

Well, tough to diagnose since you really didn't have a baseline. The vibration could be a balance issue, could have some rubber buildup from the track, the tire could have rotated on the rim, etc., etc, etc..

The cording is probably (and I am not sure about MMP) based on the track and the higher stress on that side of the car. Camber setting of -2.2 up front is really not that aggressive and will wear out the outsides. The -2.0 in the rear isn't that bad but that depends on the width of the tire and your suspension compliance. Tire choice would also contribute based on sidewall stiffness.

Brain hurt yet?

I think you are wise to "start new" with the race shop in a couple weeks. The one thing I have found VERY valuable is that my shop charts all my settings everytime the car is in and I have a historical record of settings as well as feedback from the track (driver input, tire temps, ambient temps, track, etc.).

blake

Great advice Dell - thanks! I am really enjoying the entire learning process. I had my "a-ha" moment on the track early last summer when driving events began to happen in slow motion rather than at a frentic pace. That first feeling of "bliss" was intoxicating, and I have really been enjoying my track experiences ever since. There will always be more to learn, but as they say, "it is all good!"

So between proper track tires, alignment, corner balancing, race seats, harnesses, roll bars, GPS systems, video cameras, sway bars, motons, shock valving, toe links, brake fluids, rotors, brake pads, track wheels, and the list goes on.... I still have a LOT to learn... But it is so worth it, and I have you Rennlist guys at my back!

-Blake