You mean Fritz from the factory who actually knew what he was doing when he built the car?

If that's the guy, then you have to take your measurements from the center or your torsion bar tubes and compare that to the center of your wheels.

The optimum euro height for the rear is when the rear wheel center is 1/2" below the center of the rear torsion bar tube. Up front, the center of the front torsion bar tube needs to be 4" below the wheel center. This is from the "Spec Book" that Fritz goes by and he didn't give a rats ass how it looks either.

Cheers,

Joe

YES!!!! THAT Fritz! Now you are talkin MY language!

Well I got one side free and I COULD go ahead and reindex. BUT what id LIKE to do is swap the arms so I dont have to buy new bushings.. I need to search on this one and see if it works. BUT ID have to pull the damn rocker panels off... AAARRRGH.. I KNOW Fritz hated it when the Porsche stylists insisted on this panel.. lots of swearing in the assembly plant that day... all in German of course.. SHIST!

And thanks for the specs.. unfortunatley it sounds like I cant measure that anymore cuz its all apart.. man I hope i happen to nail it on the first try so I dont have to get those spring plates off again..

[QUOTE=calling911;4315075 BUT what id LIKE to do is swap the arms so I dont have to buy new bushings.. .[/QUOTE]


Before you go all crazy on this bushing thing ( maybe it's too late ), what makes you think they're all that bad? I updated my '74 with stock '78 adjustable trailing arms that have over 250K now and they're just fine.

Joe

You know, I was just doing some reading which brought me to the same conclusion.. Wayne's book says dont do em unless they are cracked.. now mine are certainly not round anymore but they are ok.. I was thinking.. what about swapping them side to side??? I have been searching and I cant find a thread about this.. I did see one reference to it as a cheap trick but thats it.


In my case, its a lot of work to swap them cuz I got to pull the lower rocker panel thingy off to get the covers off to be able to take the spring plates off completely.. what do you guys think?

Im fighting the other side off while I wait to hear back from you guys.

FYI Early US settings
http://forums.pelicanparts.com/uploa...1227212272.jpg

and rear

http://forums.pelicanparts.com/uploa...1227212323.jpg

Thanks.. thats probably correct for my car and subtracks the stupid crash test bumper height they added in.. BUT.. since I could not easily remove my torsion bars and didnt want to go that whole route I just went one spline which should give me 1/ 1/2" drop.. 2 splines was too much.. it dropped 3".. you need to rotate the inner spline to get the increments smaller according to Waynes book.. so I am lazy and just went for the 1 1/2"... I bet it comes out pretty close to "Euro" spec which is 25" in the rear to the fender lip.. should be about 25 1/2" and my front might be correct at 26".. I keep reading 1/2" HIGHER in the front even though I was told here lower but maybe thats in reference to the torsion tube and center axle as opposed to floor to high point of fender well..

What stlrj said.

And, for the record, mine ends up pretty close to 27 front / 26.5 rear when I adjust it to the "fritz" method (which I like and use).

Adjusting the front will change the rear fender measurement a bit - maybe try adjusting the front to factory spec ("fritz method") and seeing where the rear ends up. Might not need any adjustment at all.

Other things that will affect ride height:
Putting gas in the tank will change the front a lot and the rear a bit. Jacking up the car and setting it back on the ground will really change the ride height until you roll the car back and forth or go for a drive.

Hmmm.. well.. Im not happy. One spline dropped me down to exactly 25" and now my car looks slammed. This is what everyone calls Euro here but I dunno.. doggone it.

Now the front is at 27".. maybe now if I drop the front the rear will come up.. oh the joys of not paying attention in math class. Any kids reading this.. GO TO COLLEGE.. Im an idiot.

While I wish I adjusted the front first now, I think the opposite would have occured.. I would have gone down in the front and up in the rear... based on my results anyway... just maybe when I drop 1.5" I will be right on target.. who knows. I'll report back for anyone interested.. I can now see why a shop charges $500 for this job. $500 is CHEAP. I havent even aligned the car yet.. and now my car looks like its crippled with all the camber in the butt end :)

EDIT: Dropped the front to 25.5. Didnt bring the rear up.. in fact, it dropped a 1/4". Im jumping up and down on the rear fender to loosen it but I guess I'll take my slammed car out for a drive and see what it looks like when I get back. I'll probably be going back to the same height in the rear until I can justify buying adjustable spring plates.

EDIT: All the problems are solved however.. took it for a drive and its like a new car..

You took a shot in the dark by dropping one spline and, unfortunately, you missed. The torsion bar has a different number of splines on the inside and outside--40 on the inside and 44 on the outside--so more precise movement can be made by rotating the bar one way and the spring plate the opposite way. It's not too complicated and there are many threads to describe it. Before you get too frustrated, take a breath, think about the hassel this might be, get a few beers and hit the search function, and decide if you want to let a pro (experienced) shop do this dirty work. Could be worth the money, or even the hair that you could pull out;)!

Each time you unbolt and bolt back up the T Bar plate you get faster.....ask me how I know....

I now have adjustable spring plates and haven't touched them in years....Love it..

Well, sort of a shot in the dark. I weighed what it would take to remove the bar and took a calculated risk. That being said, although I do not like the way the car looks it is handling very nice right now.. no more darting around, its not twitchy and it seems to respond quicker to steering corrections.

This could be due to the 7+ hrs of work I put into it but even if its all psychological it STILL worked. :)

I really hate the way it looks though. The rear tires are even with the fender lip.. I know many strive for this but Id rather have about 1" of clearance. I played with the front some more and the bottom line is 24 1/2 on the left rear and 25 on the rt rear.. rt front 25 1/2 and left front 25 with no driver in the car. Im thinking its pretty close with my 170 lbs in it.

I hope after I take it out some more I still like it.. otherwise, yeah, I'll tear the rockers apart, pull the torsion bars and index them about 1" higher.

It sure was nice driving down the road and just touching the steering wheel as opposed to hanging on and correcting constantly.

thanks for all the help and advise. Sorry about my crappy attitude... I didnt even look at the stock market today.. I cant look anymore.

Yeah, I'll watch for some used ones.. would be a hell of a lot easier than pulling the torsion bars.. Ive read the horror stories about getting them out.. I dont even want to go there.. and I have absolutely no interest in downgrading my suspension to bigger torsion bars..

You know, one of the benefits of doing lots of racing is you get all that out of your system.. all that money I spent is now paying off in savings of not buying all those aftermarket parts in order to "go faster". ;) Took me tens of thousands of dollars to realize there arent many cars out there that the avg person can drive to its limit consistantly... especially on the street of all things.

Well.. onto the classifieds to find some adjustables ;)

thanks

Welcome to corner balancing. I had my car lowered and corner balanced by Jeff Gamroth's shop here in Portland. When I got it back, my corner weights were distributed just about perfectly.

My wheel arch ride heights are:

LF 24 1/8 ...... RF 23 7/8
LR 23 5/8 ...... RR 23 1/8

For handling, it is not the ride height but the weights that make a difference.

My car handles great and who cares if one side is higher than the other.

As I stated, I will NOT be corner balancing my car. I just wanted to get rid of the naughty behavior.. it looks like the front was too low but I am not sure.. I am wishing I just raised the front now but I really need to get some seat time in to know for sure.. last night might have been more phsychological than anything. I have a 2 hr trip to make today so I should know later today.

Could be the camber change too.. I still havent taken the camber out.. Im guessing -5 degrees in the rear right now which is pretty insane for the street. Im surprised the car isnt wondering around... But tire wear will be a factor at -5. FOr the street you want as little camber as possible in the rear so you can tail wag now and then for fun ;)

I also discovered why I miscalculated. It turns out when I stop my car it sits at a settled height.. As the engine compartment gets warmer (mainly the Koni shocks) the car lifts 1/2" in the rear! If I had known this I would have not made the adjustment I did. I can only guess as the gas gets hot in the shocks it expands.

So all in all this has been interesting as usual.. Its amazing what you learn when you diy.

Looks like adjustable plates are out there for $100 used.. however.. I just realized I will STILL need to pull my rocker panels apart to get the caps off to get the plates off... so at that point.. well, I guess the adj. plates MIGHT save me the hassle of freeing stuck torsion bars.. and I cant stand reading stuff people have gone thru to free them! One guy used a come-a-long attached to his truck and it STILL didnt budge! NO THANK YOU MAAM! :)

So maybe $100 is a good investment :) time-wise

EDIT: Harry can I see a pic of your car? Man you have that thing slammed! No fender rub that low???

JP - don't take this too badly, but you really need to read up on 911's. You say you have been around race cars, but some of the things you posted are really odd. Perhaps they may apply to other types of cars, but... (I'm not picking on you, really)

It's nearly impossible to get negative 5 degrees of camber in the rear of a 911 without modification to the rear suspension. I understand you are just guessing at the number, but if you indeed have anything near that something is wrong with your rear suspension.

Camber is not as big a factor in the "dartiness" (is that a word) as is the toe. On a 911 you do not want toe out as it will be more likely than normal to oversteer (by a lot). You may want to check the toe. I have 2.5 degrees of camber in the rear of my Carrera, and it is perfectly controlled and controlable with a bit of toe in. I can toss it into a corner without feel of the rear end looping around.

As for your comment about not wanting to corner weight your car, you really should reconsider. In your initial post you complained about locking up a corner prematurely. This likely has more to do with your odd weight distribution than ride height. There are homebrewed methods to corner weight your car. Search for it here.

I'm a little surprised that your car would rise 1/2 inch with a warm drivetrain. The shocks are not springs so getting warmer will not cause them to rise (or lower as would be the case if they behaved like springs). The gas in shocks would indeed expand when warmer, but they would not raise the car as the pressure wold equalize across the shock valve.

What usually occurs when a car has been raised on jacks or has had suspension work performed is the car will sit slightly higher. But once the tires have splayed out and the bushings equalize, the car will sink to equilibrium height.

You should also reconsider working on the bushings. Worn bushings (even if you flipped them) will result in suspension changes in a dynamic situation and the ride quality will not be optimal. You will be amazed at the ride quality and the handling once you have replaced the worn bushings. There are rubber bushigns available on the market if you want rubber. Too many times folks think their 911 performs just fine...until they experience the difference between worn bushings and new bushings. Even with hard or solid bushings, the ride will be greatly improved over worn bushings.

+1 on Souk's comments. Neatrix rear street bushes are not that expensive or hard to install.

Jeff really knows his stuff (but then again, Alex Job thought so too). Other than "high points" in the road, I have no problem scraping the bottom of my car.

This is a very low shot with 205/55-15 Yoko ES 100's:

http://forums.pelicanparts.com/uploa...1124845562.jpg

Here is approx. 24" measured at the fenders vertical to the wheel center ( a little less than 24" at the front)...but also corner balanced - I have a gap (as you can see) above the rear tire (16" tires/wheels) and the rear fender lip, probably close to an inch. The lowerest point under the car is the rear swap bar arm...but it's probably not much lower than my BMW with stock Sport ride height which I use as a daily driver.

(Edit: I am a big proponent of measuring ride height and setting rake by measuring at the t-bar centers. All other measurement points are subjective, but I present the values measured to the fender lip as it's a commonly used reference)

http://forums.pelicanparts.com/uploa...1224498296.jpg


http://forums.pelicanparts.com/uploa...1224498308.jpg

A well set up 911 with good tires, alignment, and corner balance is a great car to drive no matter what the height. Do not forget to inspect you front and rear bushings by looking to see if things are close to centered.

Only check ride height after you have checked you tire air pressures.

Torsion bar acces covers do not have to come off 911's up through 86. Not sure about the later ones.

See this angle calculator to save you a lot of work.

http://www.rennlight.com/cgi-bin/spring.cgi

And here is a shot of my"slammed" car in action at an Autocross (my son is the passenger). FWIW, my car does not bottom out.

http://forums.pelicanparts.com/uploa...1130383659.jpg

http://forums.pelicanparts.com/uploa...1130383725.jpg

Lockup gone, rocking fore and aft gone, squirrely steering gone. I think I did quite well especially since I know nothing about 911's according to you. Just got done with a 2 hour drive and its like a new car.

I couldnt be happier with the results.. now the slammed look Im not pleased with but oh well.. as I said I was after peformance not appearance so I'll stick to that. Actually thats not true, I said I wanted it stock.. but getting to stock is about 4 hrs more work I dont have time for now and my car now drives wonderful.. hell it was windy as hell and my car stayed rock solid down the freeway.. and get this.. my 3rd gear crunch is virtually gone.. very odd.. I think I read somewhere overfilling the 915 can cure some issues.. I need to find that again and "read up".


BTW gas shocks effect ride height.. you might want to study that up a bit.. do you have another explanation for my car raising itself without me touching it besides heat? I dont.

Im gonna go study 911's now. :)