Ed Hughes

All I know is that all you need is some rear wheel spacers and you're good to go! Thankfully that thread died...

It is about contact patch. You have to "pre-compensate" for the movement of the wheel/tire toward a positive camber situation by starting with some negative that will vary from car to car and track to track. Roll center could effect settings as it is all done as a package with toe, caster, pressure, spring rate, dampeners, etc.

I'm no expert either, this is definitely a science with maybe a little black arts.

Ed Hughes

I thought about those camber tires in all of this. Something about those doesn't add up.

Foxpaws, I think you'll find 911's respond more to toe and camber for turn-in as opposed to caster.

Auto_Werks 3.6

Ed is probably right on this one, but you can always do some experimenting and report back!

I don't remember if you said this is your first 911, but if so.... You should seriously consider doing some autocross events, especially if you are testing new settings. These cars have a distinct personality, and it might take some time before it come naturally. A big parking lot is a good place to learn about trailing throttle oversteer, and understeer to oversteer transition etc etc etc. If the setup is not right, the car might do some really strange things. It's probably better to find these things out in a controled environment.

whalebird

^^^ definitly. Modest camber for street and lite track use will not wear the tires abnormally, I think the really smart guys will chime in with some specs, or a search in the archives will get you some good advice. For me, I would adhere to the proven specs, then adjust accordingly to personal taste.
Sheeez; that tire wheel spacer thread still kind of bugs me.
Fox...be conservative with the rake/camber/caster quotient as the rear engine chassis needs little in the way of "bite" on the front. I look forward to your findings.
And fox, do a search for Rlist member RJT. She is another gal amongst the folds here and EXCEPTIONALLY wise in the ways of Porschedom. Find her profile, click the link in her sig. and see what her job is. She is making history right now in Porsche motorsports for sure.
She has won a few "pagents" with her concours restorations, and...well, she is pretty too. It's a great community here and welcome.

foxpaws

Thanks everyone.... wow, you are nice folk.

I'll look up RJT - women in the car biz aren't that common...

I am lucky - this is what we have at work - so setting and re-setting isn't that big of deal for me. Although the 911 is a tight fit - just like the Miata - we had the 911 up on this lift after my mechanic did the PPI and said that I had to see the underside of the car - they are about as small of wheelbase that will fit on this lift set-up.



I also have some friends who race BMWs at High Plains here in Colorado - that is where I will be tracking the car - they are among the leaders in some sort of SCCA class, so they can help out a lot as well. I have had a '78 911SC as well as a '74 914 2.0, so I know a little about having the engine behind you...

As far as concours - I appreciate the amazing vehicles and the work involved - but, this car I really bought to drive. The caddy wins the car shows (but not concours - it is really modded, think modern day hot rod - it will beat the little 911 in all straight times, easily, Northstars are detuned racing engines, and when you tune them, port them, make sure they can breathe - they run... fast...), but I don't want to be a wax monkey to two cars...

Whoops - forgot - I think the camber tires are by Optima Sports -

Ed Hughes

Computerized alignment may be simpler and a bit faster, but it is the knowledge that is most important. If your guys have no p-car experience, encourage them to ask questions of those who do. Remember that the very fastest rear engined Porsches in the world today, including the current ALMS champs, use strings for set up of alignment. Heck, the racing world for that matter...

foxpaws

Mr Hughes - we design and build alignment parts for cars - we are manufacturers. We know alignment.
We can use strings and tape too... but it isn't really sensible anymore.

Now, the guys in the back aren't afraid to step away and say it is beyond them - but, they also have 100s of years of experience. I am not afraid to put the little 911 in their hands, heck, they got rid of a lot of the understeer on the Caddy - and I am putting a lot of ponies to the ground in that thing.

But, I love to find out what others know - there is a lot more knowledge out here on this site than we have regarding this specific vehicle. You drive 'em, race 'em, tinker with them. But, I am most interested in the tinker part... tinkering is fun.

We also build million dollar suspensions for trophy trucks, and have designed this cool new vehicle for delivery out of the V-22 Osprey... So we do a ton of nifty stuff. I am just anxious to get in the little 911 and have some fun.

Makmov

we used sticks and pins to set alignments because we could never find a shop that could to it correctly.

If you want dencent tire wear.

Camber -1 -1.5 F&4 It would like more like -2 -2.5 but it will eat tires.

Toe -1 F 1 R

4 corner balance the car if you have the adjusters to do that, I don't think your car has them though.

Ed Hughes

No need to call me Mr. Hughes- Ed works fine.

That was not meant as a snub on your guys, or your products- I tried to be as polite as possible in suggesting that they go into this with an open mind and as a learning experience. The fact is there are some great folks with the experience in setting these cars up which is not necessarily present in all pros adept at setup in other vehicles. From a safety point of view, I don't want to see a body or car hurt in an ill-handling car. The best computer equipment isnt the determining factor here. My apologies if I offended you or your company.

Makmov

However, Ed is correct. Trust me, we have taken cars to shops with the latest greatest Hunter racks and they still don't get it right.

I have asked to have my car set to RSA specs and get deer in the headlight looks.

The tool is only as good as the opperator.

An ill handling car is an accident waiting to happen.

Especially an ill-handing 911.

foxpaws

Ed - no offense at all - really. I was just trying to show you we aren't just some alignment shop at the end of the street... But the guys have walked away from more than one car - Z4s for instance - and we have had some Italian iron up on the lifts and they won't move anything much beyond spec on them. Although we had a Lambo in that someone lowered, a lot - blick - they stepped away from that one... it was bad, and just waiting to get worse.

I am here to learn - already I know not to rake the caster out over 1 degree, camber is pretty much the same as everywhere - you know it when you feel it (it won't be -2.5 for me Makmov - I like my tires... smile) look at ducks in the front...

And I won't be pushing the car that much - it is going to be a fun day at the track car, I am not that competitive. I want to enjoy it taking it over Independence Pass too - but, I don't take big risks, life is short - I don't need to make it that much shorter by being dumb.

And the machine doesn't make a good technician - like I said we can do it with string and tape, but there isn't any real reason to. The techs just use the aligner like a tool - you can tighten a nut with a pair of pliers - but why - there are better tools for the job. You can set alignment with string and tape - but why - there are better tools for the job. We have adjustable camber/caster/toe gauges that you use at the track when you want to set it for the track, and then set it back for the street. They have a level with a bubble in it - they work great - but take time to learn and to use. Lo-tech solution, but if you have someone who knows what they are doing, they can do a better alignment with that then a poor tech with a expensive Hunter machine at his disposal.

rusnak

That is an intensely competent "shop". We should be asking them to jump on here to report their discoveries. We should be so lucky.

One word about RJT- her passion for Porsches and contributions through racing and concours do indeed qualify for a special place in this small community.

foxpaws

Rusnak - we actually don't do much with porsches - I am trying to convince the guys that it could be worth it to look at doing something with them. I hope they are going to experiment a little with my car. We have to look at a lot of different things before we commit time and resources, things like will the people who own the cars be willing to alter their cars, some groups do, some groups don't.

We do a lot with off-road stuff... this was a recent project

dshepp806

THAT is KILLER!!!!!!!!!!

Best,

Doyle

dshepp806

If you've NOT done Porsches before,..I think you guys' are in for a treat.....hopefully (of course) a good one.

Best to you.

Doyle