Amber Gramps

I went out today and took the old tape measure to the fenders. 25 1/2 front 25 1/2 rear. The books I have all talk about MM from center of wheel to this, that, and the other thing. everyone here talks about fenders and "search" isn't giving me anything. it's an '88 cab on 16's and correct tires. it looks good and rides great. just curious. thanks guys.

EDIT: try to ignore the number of posts thus far....

imcarthur

The front should always be 1/2" higher by wheel arch measurement - which is not really that accurate anyway. You want a 1 degree pitch forward. Use an angle finder on the door sill. The car should be level.

The only totally accurate method is the angle of the springplate - when not connected to the trailing arm. Then you use Will Ferch's angle calculator here . Once you have the rear set, you dial in the front with the 1 degree pitch.

Ian

Amber Gramps

Now I see that I only gained a 1/2" in the back with my rear fenders now at 26. the big diff. is in the fact that when wife and I drop our collective 425 pounds in the car it didn't drop to the rubbers today.

Peter Zimmermann

douglas: "True" Euro height is, using the fender measurement method, 25.5" F and 25" rear. As you know, the car has to be on a level floor, and the measurements must be made vertically, through the wheel center, from the floor to the first "pretty" (painted) surface. I've looked at the pictures of your car and it looks very good - someone might have dropped just the front by a small amount, which is easy to do, just to gain a slightly "racier" look.

Amber Gramps

Pete, in the case of this car I think neglect took the front end to 25.5" not modification. Man is it a sweet ride now. Now all I need is a clean bill of health at Red Line and some A/C and she'll be ready for daily driving. Did I tell you how sweet the ride was to San Diego? It's a new car other that the fiew remaining laundry lists of things that need work.

Amber Gramps

With a 25.5" front end due to sag, do I have a bump stear problem? I do feal like every little bump jerks the wheel a little. Can this be corrected with a kit without an alignment or should I hold off and do the tie rods, struts, and alignment all at the same time?

Peter Zimmermann

No bump-steer issues at either stock USA, or Euro, ride height. Your wheel "jerk" is probably a combo of alignment and old, really old, Boges. If you're planning Bilsteins for the front, and tie rods, plan your alignment for about 100 - 200 miles after those items are done. You know who to take it to, but if not pm me for the name and number. Cheers!

Amber Gramps

Is 20 years 5 months and 70,480 miles old? sorry, had to.

Amber Gramps

Wow, 4-1/2 years later I've finally got the Bilsteins on up front to go with the back I did a while back. What a difference.

Ride height is now 26 front 26 rear. ....so we'll let her settle in a bit and lower the front back to 25-1/2. Can't believe what a difference good brakes and shocks make. Can't wait to have the energy to finish up everything I've got ready to go.

MillenniumFalcon

Glad to hear you like your Bilsteins...I think I'm going to bite the bullet and get a pair for the front on mine too. Did you really notice a difference? How differeent is the ride and handling?

. I have 205/55/16 tires on my 911, and my rear trim height (non-adjustable arms for now) at the moment is about 0.90 inches. Which is way too large, according to any spec (USA or Euro). My rear fender lip height is 24.75.

The Porsche spec's for trim height, and the Euro/USA rfender lip heights that I see being thrown around have really confused me. And I am dealing with handling issues right now after a suspension rebuild and ride height change.

Front fender lip height is 25.25 and the lower control arms are nearly level (angled slightly downwards towards the wheel). Tie rods are almost perfectly level too (angled ever so slightly down towards the wheel)

If I were to raise the rear of the car any higher, it wold bring the rear trim height even further out of spec- this is what confuses me!

theiceman

Dave front should be 1/2 inch higher so looks like front 25.5 and rear 24.75 is pretty good to me .

MillenniumFalcon

Thanks Iceman. I'm busy trying to figure out why this car handles worse than my pickup truck right now (after an alignment, too!). It has become a little aggravating

Taking it one item at a time. I'm beginning to think it really is mostly the crappy strut inserts that I have in there.

Peter Zimmermann

This is "Euro" ride height. 25.5" F; 25" R. Measured on a level floor, vertically through the wheel centers, with the tire pressures set at 29F/34R.

Amber Gramps

Dave, it may well be your strut inserts. I can't believe the difference they made on my car. Ya, my doors got dynamat and my carpet got a layer of 3/8" felt sound mat added since I last drove her, but I can't attribute wheel feedback to the carpet......it has to be from the struts. Now, when I stomp on the gas the front end comes up a little, but it doesn't totally change the attitude of the front end like it did with worn out inserts. I could lift the front several inches with the blip of the throttle. Fun in the seat, but not good. Now she is solid and doesn't wander all over the road with every little bump she hits. Almost like driving on glass now. Let's just say I didn't want to take her home last night.

The Boge inserts literally fell apart as I took them out of the struts. The fluid was thinner than water and I resorted to rolling up blue shop towel and stuffing them in the struts to get all the fluid out.

My secret here is to always purchase at least some of the parts I need from Steve Weiner. Why? Because he answers the phone on Saturday afternoon when I'm in a panic over something stupid. He always walks me through it and reassures me I've got it handled.

In this case, if you don't know how old your inserts are it's time to replace them. Steve can tell you what you need. In my case I needed Bilsteins HD inserts for Boge struts. Solid difference.

MillenniumFalcon

Amber- my KYB front inserts aren't worn- they have about 400 miles on them now. The car floats and reacts badly to imperfections in the freeway surface, and mildly agressive lane changes at freeway speeds cause some uncomfortable undulations. It feels as though there is almost no rebound damping... I guess there is also the possibility that I have heavier than stock torsion bars in it, but I forgot to measure the rear ones when I had them out for my suspension lowering. It's the transitions that feel ungainly, not so much straight line driving on smooth pavement.

Pete, thanks for the picture- that helps. Tire size will affect the fender lip measurement as well, by as much as .50, right? Perhaps I am splitting hairs here, but I am trying to rule things out, one at a time- I really need to get the car setup safer/better.

I need to grab a book and read about suspensions.

I am wondering how rear toe-in affects handling, as opposed to setting it at zero- I don't understand why my alignment guy set it with toe-in.

Here are photos of mine with fender lip height of: 24.75 rear, 25.25 front with 205/55/16 tires, pressures 29F/34R.