Auto_Werks 3.6

Also, if you want an idea of what you can get away with, check out this thread on Pelican Parts;
http://forums.pelicanparts.com/porsc...ht-stance.html

There are some wicked looking cars!

foxpaws

thanks werks - some wicked looking beasts there...

Oh, whale - this is what we see - gak... camber might be a bit too negative on the rear...



We actually get problems with newer Mercedes too - since they are made to 'squat' when they start to get to speed they come with a bit of negative camber built in which then flattens out at about 90mph, but here in the States we don't have an Autobahn (actually Highway 64 across the top of New Mexico is darn close though), so they have a habit of wearing out their tires.

Auto_Werks 3.6

hahah, come on, that one's barely negative. this is how it's done:

personally, I hate the stretched look more than I dislike the camber.

I figured that's what you meant about camber, just wanted to make sure you weren't trying to zero it out.

whalebird

Funny thing on the Benzs. In 2000 when the new S-class (220 chassis)came out with the variable ride height we had a ton of complaints about the tire wear. I had one problem customer whos car I had done an alignment to. He still complained. The factory specs were not working here in the US like they were in europe. Mercedes sent their engineer to us and wanted to see the alignment. I put it on the rack - went thru the cars alignment protocol with the computer, up, down, middle etc. Everything was on. While driving the car, I said we should take some tire temp readings and see whats happening. He looked at me puzzled and said "you know how to take tire temps?". To his amazment, I had a tire pyrometer in my tool box and we spent the day driving an S-class on the freeway. We took the wrenches and started making adjustments on the road. When we got it where it wanted to be, we put it on the rack and recorded the specs. He took those back to Benz and studied them. I received a written comendation from Mercedes and was paid $100 an hour for my time. Those were the specs we used from there on. Fun day.

whalebird

Autowerks, your car looks pretty knarly. I like a low 911, but there is a limit. The suspension points don't play well when it gets REAL low. Shock mounts need to be extended and CV joints start to fail(on a mostly stock chassis), but done properly, it can be cool. Getting the car as low as possible was how the factory reached speeds of 180+ in stock bodied(narrow -early)cars without wings in the late 60s/early 70s - those guys had *****.

Auto_Werks 3.6

Whalebird,
Thanks for the compliment. I would consider my car to be about the edge of what you can do with mostly factory components. Now that you've got me thinking, I do have some pretty stiff torsion bars under it, so I won't have as much travel as a stock car. I am still running rubber bushings and stock spindles though. I have had a bone stock 911 SC that was a little lower, and it was probably slightly outside the performance bubble but it looked pretty cool on RSR finished Fuchs.

I'm usually trying to walk the line between what the consensus says "should" be done, and what can be done. I've driven that car all over the country (to the tail of the dragon), done solo competition and had it on the track pushing 300+hp through it and the chassis really never hiccups. The thing is like a zen experience. The car just does what it should with little effort. Everyone's results may vary some, but the bottom line is that he can come down at least a little from where he is, and the rake probably isn't a game ender if it's not spot on.

My car is also probably not as low as it looks in the picture. The skirts and the splitter help with the look, but it sits up a bit, especially if I throw my 17" wheels on it.

You should check out the link I posted to Pelican. There are a lot of guys there running a lot lower than I am.

PS, your story about MB is really cool, thanks for posting it. It's interesting when engineers get schooled by practical people

Ed Hughes

As mentioned, even experienced race shops (other types of cars) can hose up a 911. They are different. No need to reinvent the wheel. If you're tracking, some nice monoballs front and rear, some poly-bronze bushings from Elephant Racing, some heavier t-bars with shocks valved to match the heavier springs, a proper aggressive alignment and a corner balance-riding on some great rubber-will make for an awesome ride. You can hang with many newer Porsches and Ferraris on the twisties.

I reminded myself of this early this past Saturday morning. A new CTS with the Z1 585hp motor was between me and a CGT and an F430. I had to smell his differential burning up the entire way up Palomar Mountain.

foxpaws

Whale - great story about the S-Class. Did you ever figure out why the difference between the US and Euro specs? Back then it probably wasn't the speed -

Autowerks - how about making that 'she' can come down a little -

Mr Hughes - odd about the CTS-V - it might have been driver error - they are pretty amazing vehicles.

Ed Hughes

Amazing no doubt. But, it is a high powered 4100lb car. Lots of stress when you climb over 4000 ft in about 7 miles. I really don't think they are built for what we did. It was a GM press car, so it has had a short but hard life. Ironically, I just got my new AutoWeek and it is the cover car.

Funny, but there was a monster Viper that had almost eight hundred HP at the wheels on the run-supposedly about $200k in upgrades-weaping some oil at the top. I am definitely bringing the group down in stature with Ruby, but she holds her own on the hillclimb and comes out no worse for the wear in the end.

rusnak

^^ This does not surprise me one bit. WB knows how to troubleshoot, which is what I noticed on the steering diagnostic thread.

Ed Hughes

Ruby was almost as low as AW's car above, but she's now up a bit and drives a lot better. I did raise the spindles last year, and that made a huge improvement. Also valving the shocks to work in the new height range and matched to the heavier bars are mandated too for best results.

Auto_Werks 3.6

I swear guys, It's not that low, sheesh you'd think I had broken the ride height altar or something.

Rusnak, I agree WB has made some pretty impressive posts... always interesting to see what comes next.

Fox, whoops, loud and clear. I was going to derail the train by saying that I don't beleive in asigning a gender to inanimate objects, then I realized I'm just not the brightest crayon in the box tonight.

Ed, Don't get down on Ruby... I would rather have your car (hmmm, saying "her" here would have made some sense, but I'm not willing to come off my previous statement) than any of those cars, ESPECIALLY if I had to write the check. I think there is something to be said for driver input. At the last track day at HPT someone complimented a guy in a paddle shift Ferrari 458 for his downshift???? You are helping defend an art that is quickly becoming lost.

rusnak

Auto, I'm stuck on your comment about burning the outside edge of the tire w/o increasing neg camber, if the car is lowered. I would have thought (but have not really) that roll-center height would have to be high in order to roll the outside edge? Can you expand on that...I admit I'm not the brightest knife in the shed right now. -- My GF came over with a bunch of Rocky Patel cigars that she got when they were handing them out at her work. And as Ed can attest, cigars and Porsches a fine evening make.

Auto_Werks 3.6

Rus,
We're all on different pages... I had misunderstood one of her original posts. I thougt she wanted to zero out all the camber on the car because it didn't look good. I was simply saying that if you lower the car, then dial out all the camber and track the car you will wear the outside edge. She was however talking about excessive camber like the picture of the honda RSX above. It's "what the kids are doing" these days, not a performance thing.

I wouldn't think you would actually have to add more than a normal amount of camber when lowering it... in fact it may actually pick up some camber when you drop it, right?

foxpaws

Autowerks - the car is a 'he' (mine all are, and I do believe in assigning gender to certain inanimate objects, well, just 2 - cars and computers) however the person doing the lowering is a 'she' (me - I am a she )

When I lower it I expect to have it get in the negative camber range, a teeny-tiny bit of negative camber is OK - but, rather than try to improve handling with a bit of negative camber I would rather rake the caster a little - you get a similar effect - bite into the corners, but without that nasty tire wear. So, I'll try to get the camber as close to spec as I can, or very slightly negative (.15 or so) and see what the chassis is comfortable with in regards to raking the caster (going positive).

But, with all this talk about negative camber - we are helping out a guy at Car and Driver with a review of some new tires that take into account that people like pushing out the camber a little - they are made with extra 'stuff' on the inside, to compensate for the extra wear you get when you run negative camber. I don't know much about them, and don't really understand what happens when you rotate them - do you have to set the camber the same on the front and rear wheels, that isn't clear to me either...