Why does my ride height look so high even though it's lower than spec

[Wil Ferch]

jwakil....I almost started down that same ( incorrect) path....that possibly high-pressure gas strut inserts are fitted...Koni/Bilstein/etc....but as you say, if that was the case, then the TB centerline dimensions would be altered.

There was a large shock spacer used for some years of the SC.... but only as intended for the US market...and *I think* only sometime in the later 70's.

To recap....we can "bank" on these facts now.

- lower A-arms are relatively flat or properly "angled down" very slightly. The amount of lowering "margin" you have is to get these to lay parallel and horizontal to ground. The amount available to lower further might only be 1/2" or less....from the sounds of your description.

- ground to front fender lip measurement is about 26"....not really all that uncommon for unaltered US SC's....but that alone says maybe you could come down 1/2".

- your 215/60-15's ( hmmm....triple check the sidewall description for size) exhibits a very small rolling diameter, and certainly less than spec expectations of ~25". I think the "visual" problem is almost all in your tires...combined with perhaps being 1/2" higher than you can be.

Vancouvertechies' picture seems just about right. Maybe have him measure ground to fender lip and ground to wheel centerline?...just for giggles?

[RSTarga]

I agree that tire doesn't seem right 215 60 vr15 on a 6" wheel should be much higher as that tire should be on a 7" wheel. The correct size is 195 65 vr15. Are those 6" wheels?

[Wil Ferch]

However....

195/65-15 would be-->
195 mm = 7.68"
7.68" x 0.65 = 5"
15" +5" + 5" = 25" rolling diameter

compared with ( theoretically, and not "worn")
215/60-15--->
215 = 8.46
8.46 x 0.6 = 5.07"
15 + 5.07 + 5.07 = 25.14"

...not much of a difference to write home about. 205/55-16 would end up at 24.9"...all essentially the same. Splitting hairs.

Mounted on a 6" vs 7" wide rim would affect the squareness of the contact patch....but will ( guessing here) not have much influence on overall rolling diameter.....certainly not the variance that the original poster is saying by measuring a MUCH smaller rolling diameter for HIS 215/60-15... he says 24"....that's a whole inch less than "it should be" by calcs with the other tires.

If you look at the original photos and 1.) lower the car 1/2" as was mentioned is probably do-able and proper...and 2.) use a tire that has 25" rolling diameter instead of 24"....then these 2 things alone should make the "visual" a whole lot more normal.... no?

[911pcars]

A larger diameter tire/wheel would fill the wheel wells more, yes? While the tire is indeed larger than normally used, this isn't making a difference in the space above the tire. This tells me the issue is the adjustment to the suspension ride height.

Sherwood

[Wil Ferch]

Sherwood:

We need to be real careful here with semantics as I made a big gaffe before and don't want to do another one.

Yes.... IF ....all the 3 tire sizes mentioned are indeed 25" rolling diameter (as they SHOULD BE by calculation and by tire specs)...then you are correct. All three would then show the SAME air space above the tire....meaning...work on the ride height.

But ......

What we haven't fully reconciled is the fact that all the 3 tire sizes mentioned should have 25" rolling diameter.... yet the ACTUAL TIRE the original poster has....even though labeled 215/60-15...and even though it should be indentical to the other 2 tires at 25" rolling diameter ...is said to be 24" rolling diameter ! A full inch less than it should be.

So I come back to my previous point---> get maybe a NEW set of same-size 215/60-15 tires ( assuming now they'll be 25" diameter when new), lower the car 1/2"...and all will look rather normal.... no ?

[911pcars]

Jwakil offered this ride height info:
"Height from ground to top of wheel well arch =26inch"

That ride height, in conjunction with the gap above the tire indicates the ride height is set on the high side. What am I missing?

Sherwood

[jwakil]

If I had to guess, I would say my wheels are probably 7inch wide, which could explain the smaller than expected rolling diameter. But this obviously doesn't explain the taller than expected wheel well arch. Below is a front view of my car. The wheel sticks out a little which makes me think its probably wider than the stock 6 inch. (The previous owner bought the wheels which is why I don't know much about them.) As you can see, the back looks really nice. But if I lower the front to make look similar, it will be way below spec and too much steering effort. Already tried that, don't want to go there. Based on my A-arm angles, I am now about as low as I can go. I guess the only answer would be to get a taller tire which would reduce the wheel well gap a little, but then handling would suffer too so its give and take. Just so no one gets confused, I did NOT take my height measurements while the car was on this slope. This is just to highlight the wheels.

[kach22i]

Originally Posted by 911pcars

Jwakil offered this ride height info:
"Height from ground to top of wheel well arch =26inch"

That ride height, in conjunction with the gap above the tire indicates the ride height is set on the high side. What am I missing?

Sherwood

Yea, something closer to 25" would be expected.

Could something up front be bent like a suspension mounting point?


Both R&L wheel arches of the car in the front are high, right?

[R_Builder]

Those sure look like 7's on the front to me. Rears are a bit harder to gauge from the angle of the picture, but I can tell they are AT LEAST 7's.

Nice looking SC, by the way. Reminds me of what my '78 looked like when I first got it. It appears you parking brake could use a little attention though...

[Oh Haha]

They look like 7s in front to me as well.

Here are a couple of threads that have some good side views of different settings.Lowerin to Euro ride height

911 sc lowered ride height pics & measurements please

IMO-The tires are not the issue, you need to bring the front down about .5 and it should give you the look you want.

[burgermeister]

My car is around 12mm lower than spec (118 to 120mm wheel center to tbar center). It looks a lot like yours. That's the way the cars looked from the factory. The 25.5" fender measurement is significantly lower than factory - not sure where that came from. i like it at that height, for appearance, and the ride on Michigan roads is much better that way too. If you can't stand the looks, lower it a bit!

Here are pics from the 1981 911SC brochure:

[jwakil]

Burgermiester...I think it would look a little better a little lower for my car, but now I guess it is not abnormal for my ride height setting. I will live with it since lowering further causes other issues. Here's another front angle view. The gap in the back is much less than front, which is what makes it look a little odd.

[Wil Ferch]

The 25.5"/25" fr/rr pairing was originally quoted as far back as the target ride height by Bruce Anderson before the computer days. It was repeated ever since. It is lower than "Spec" Euro.

[kiwiokie]

In this picture the front flare looks a little abrupt to me. Could the front fender have been rolled by a previous owner to fit a large wheel/tire combination?

Originally Posted by jwakil

[jwakil]

Kiwiokie....I don't think so, but that could definitely explain everything if it were true. Looking at the other peoples pics, it's hard to tell if my flare is any more abrupt than the others'.