Ride height...

djmcmath · 02-15-2004, 07:20 AM

I keep seeing other people's Porsches riding super-low. Some people just have them at the euro-spec, others have them even lower. I'm the oddball who's trying to _raise_ his car. The PO brought it down to euro-spec, and it just seems entirely too low to me. I went out and measured it last night, to be sure, and it's at 24.5 in the back, and 25 in the front, just like it's supposed to be. Only problem is that I can hear the wheels rubbing the inside of the fenders. Yes, I could roll the fenders (if I had a baseball bat), but I really can't make myself believe it would help. I could put really stiff torsion bars and dampers on, but the budget is a little slim right now.

So the question -- how in the heck do you low-riders get away with that? Does rolling fender-lips (I'd have to roll all four, for sure) really make any difference at all? Would I be totally insane (and ostracized) if I _raised_ my 911?

Dan

djmcmath · 02-15-2004, 07:23 AM

Oh -- one last add-on. The camber in the back is pretty close to 0 (according to the tire wear) and the front camber is huge -- the inside of the fronts is virtually bald, while the outside is collecting dust. Yes, I could adjust the camber so the tires wear normally, but then I'd rub worse, right?

TIA -- I look forward to the replies on this one...

Dan

David · David's Garage

With that ride height, I wouldn't expect tire rubbing problems. What size tires do you have? Do you have wheel spacers?

catuck · catuck's Garage

I am able to fit 225/55-16's all around with a lower than euro ride height. I do get minimal rubbing in the front - when these tires wear out, I'm going back to 205's up front. I have neg camber maxed out and rolled all 4 fender lips, and larger torsion bars. With the 205's I'm sure I'll get no rubbing. This on a narrow body.

So, my answer to your question? Raise car just enough to eliminate rubbing with proper camber (you will need a re-alignment). Then in the future if you want to spend the time and money, and/or if you want to race, beef up the suspension and roll the lips (if necessary).

My car handles noticably better lowered with neg camber. But, its not a daily driver so tire wear is no concern to me.

Vipergrün · 02-15-2004, 08:25 AM

I'd suspect a bad toe/caster setting up front. You typically cannot get more than -1.5 degrees camber with a stock setup. Euro height I believe is typically 25.0 rear and 25.5 front. I have 225's up front and 245's rear on my SC with no rubbing with slightly rolled fender lips.

-b

Gunter · Gunter's Garage

Dan: What tire size? 24.5R & 25F sounds good. That's what I have now but I had the same problem with inside tire wear up front. Take a look at the top of the shock towers and see if you have some adjustments left in the openings to bring the camber back to a more normal setting. I had to remove all the tar sealer there so I could move the top of the shocks to get a nice 0.5deg neg camber. I lifted the front to take the weight off, cleaned the shock-tower openings real good, opened the three Allen bolts, cleaned some more to make sure the top could slide, moved the shocks all the way towards 0/pos camber. Tightened up and went to an alignment shop to get the final adjustment. (0.5 deg neg with a small toe-in) Worked real good. I assume that you have the bump steer kit installed?

jmarenas · jmarenas's Garage

Mine is 23.5 Back, and 24.5 Front 255-40-17 back 205-50-17 front NO rub etc, spacer, with the RUFs. John

djmcmath · 02-15-2004, 12:22 PM

The tires are 205/16s in the front and 225/16s in the back. I haven't checked to see if I have any camber adjustment left, though I'm sure I do. As to the bump steer kit, I didn't see it in the receipts from the PO, but then, I'm sure there's a lot of things in there I don't know about yet ...

Boy, it sounds like I'm just the oddball. I mean, all of you are saying "I run wider tires lower with less camber and no problems." I suppose I'll roll the fenders, bring it up half an inch or so, and see if that makes any difference. Thanks for the replies, all.

Dan

Gunter · Gunter's Garage

Since you have regular tire sizes, rolling the fenders should not be necessary. Your height sounds good too. There is something weird here, these tires should not rub. This requires closer examination. Before you wear down another set, get the right alignment (Camber & Toe), especially in front. To check for the bump steer kit, shine a light past the skid plate and look at the underside of the rack. If there is a 0.5 inch (12mm) spacer, that's the kit. With proper alignment and the kit, you'll be surprised how much better your car will perform.

RANDY P · RANDY P's Garage

are you rubbing in the front or rear? How's your tire wear looking?

white87911 · white87911's Garage

I am runnning my 87 911 at 25.5 front 24.5 rear with 205/55/16 - 225/50/16 on 7" & 8" fuchs, not rubbig at all even with 2 large guys in the car and driving it like it was stollen.

catuck · catuck's Garage

Yea Dan, those sound like the correct tire sizes. What type of wheels do you have? With stock wheels and stock tires I wouldn't think you would be even close to rubbing no mater how low the car is. Aftermarket wheels with a strange offset could cause rubbing.

I bet it's the camber setting. Before you bring it in for an alignment, try playing with the camber. There are some threads on how to do this and I believe a how-to in the Tech articles section. Yup:
home toe-in and camber adjustment

djmcmath · 02-16-2004, 08:55 AM

I'm rubbing in the front, for sure. Both front fender lips have been bent where the tire has caught them. Rear wear is normal -- even straight across both rear tires. Front tire wear is very heavy on the inner edge, but almost negligible at the outter edge. I don't think I'm catching/rubbing in the back, but if I raise the front, I have to raise the rear to compensate.

Is it possible that my torsion bars are worn out? It's probably safe to assume that they're stock, and are now 18 years old. They do get tired after a while, yes? Would that allow abnormal rubbing?

Dan

Superman · 02-16-2004, 08:57 AM

I sure hope you do not have zero camber in the rear and exaggerated camber in the front. If so, your car handles "loose" to say the least. Instead, I'd guess your front has a toe problem. I'd guess you have some toe-out that you don't need. Just a guess.

djmcmath · 02-16-2004, 08:58 AM

Bump steer -- right, I'll go out and check for that now. Tnx for the info.

Dan

Jdub · 02-16-2004, 09:13 AM

Your clapped-out suspension permits too much movement. There is no reason whatsoever that you should have problems with the reasonably mild 205/225 setup unless there is an undue amount of movement.

You will need to think holistically on this one. I'd start saving for new shocks all around and redo your springplate bushings as a minimum. This will let you become intimate with the springplates when time comes to refurbish the bushings and reset ride height. Once you have the height where you want it, have a competent alignment shop set you up.

That's about the cheapest fix I can think of. Beyond this, you'd want to replace your tired tbars with either same size or slightly stronger as you prefer. Tbars do wear over time.

Best of luck,
John

RANDY P · RANDY P's Garage

are you on 6" or do you have 7" in the front? Sounds like you're on 7" If you have 7" then check the alignment then get your fenders rolled. This is assuming you do have fuchs on the car and not some funky aftermarket wheel.

Gunter · Gunter's Garage

I repeat: Have someone who knows about 911 suspensions/alignment eyeball your set-up. If you have Fuchs 6's in front and 7's rear with 205/225's NO WAY should there be any rubbing. There is something else. Save yourself some money before you go wild and have a Pelican Head look at your car. Bump steer kit has no effect on height, just handling.