This can't be right- front end height adjustment

[MongooseGA]

Originally Posted by Trackrash

My car is 24"f and 23.5" in the rear. I'm running 22 and 30 mm torsions with Koni sport shocks and poly bushings. My front spindles have been raised 22mm and my rubber bump stops have been cut down. I have a bumpsteer kit to compensate for the raised spindles and raised the oil lines in the rear for more clearance.

My car is great on the track or a smooth road. There are bumpy roads around where I live that I definitely avoid and then there are those pesky driveways...

Be careful what you wish for. Drive your car as it is for a few weeks and see how it behaves before you go any further.

I drove the car from my parents' to mine tonight. I can definitely say it's a prime candidate now for the bump steer kit. It also scraped the chin spoiler over almost every moderate dip/bump. It definitely needs to either come up a bit, or be swapped on to a much stiffer suspension set up.

That, and I think the passenger's side is a touch lower than the driver's. The car pulls to the right now. Not 'hard', but 'quickly'. I can easily hold it straight with one finger, but it's definitely pronounced with no hands on the wheel.

[scarceller]

The pulling may be that the alignment has now gone toe out? Also as you lower these cars the wheels tend to lean inward (negative camber). When you have the ride height where you want it and the bump steer kit installed you really should have it aligned.

From experience I know that these cars tend to wander a bit if they have any toe-out. For a street car that runs on roads that have crowning you really are better off with slight toe in.

[Jerome74911S]

Originally Posted by scarceller

. . . Also as you lower these cars the wheels tend to lean inward (negative camber). . .

I don't want to hijack, but this raises a question. My car had a lot of negative camber - too much for the street, but it didn't seem as if the strut top could be moved outward enough to correct this. So, by raising the height it was possible to dial in (almost) correct camber. Now the car is too high in front.

No doubt I need to refresh the whole suspension, but in the mean time, what other solution is there to gain correct camber without the car being too high? Monoball on the strut top? How close to the body can the 'normal' strut top be moved before it starts to hit the sheet metal?

[scarceller]

Correct, if you lower these cars sometimes you can't get rid of the negative camber. You also need to really cleanup all the undercoating from the adjustment bracket at the top of the strut. It also helps to adjust the bracket with wheels off the ground.

Originally Posted by Jerome74911S

I don't want to hijack, but this raises a question. My car had a lot of negative camber - too much for the street, but it didn't seem as if the strut top could be moved outward enough to correct this. So, by raising the height it was possible to dial in (almost) correct camber. Now the car is too high in front.

No doubt I need to refresh the whole suspension, but in the mean time, what other solution is there to gain correct camber without the car being too high? Monoball on the strut top? How close to the body can the 'normal' strut top be moved before it starts to hit the sheet metal?

[Jerome74911S]

Originally Posted by scarceller

Correct, if you lower these cars sometimes you can't get rid of the negative camber. You also need to really cleanup all the undercoating from the adjustment bracket at the top of the strut. It also helps to adjust the bracket with wheels off the ground.

Thank you. At this point my car's front end height is way above factory spec for a US car and that's the only way we found to get the camber near correct.

How close to the fender sheet metal can the strut top be moved? Moving it isn't the issue, it's how close to the outside is OK. 1/4 inch?

[scarceller]

To be clear, the top of the strut is in the bracket and the bracket is held to the body by the 3 bolts. You loosen the bolts and move the bracket, you don't move the strut.

And you can move the bracket as far as it allows, even if it hits the sheet metal does not matter.

Originally Posted by Jerome74911S

Thank you. At this point my car's front end height is way above factory spec for a US car and that's the only way we found to get the camber near correct.

How close to the fender sheet metal can the strut top be moved? Moving it isn't the issue, it's how close to the outside is OK. 1/4 inch?

[Jerome74911S]

^^^ Excellent, thanks.

[stlrj]

Originally Posted by Jerome74911S

At this point my car's front end height is way above factory spec for a US car and that's the only way we found to get the camber near correct.

ROW factory height should be at 27" to the bottom of the fender opening. At 27" your camber will be at zero. US height will be about 27 1/2" and your camber will be about 1/2 degree positive.

How high up are your fenders?

Cheers

Joe
87 Carrera

[Norm Faustino]

Sorry not trying to go off topic or hijack here but I noticed you have no lip on your whale tail . I have one in great condition. I will take 300 bucks or a nice set of H4's. I am getting ready to put it on the classifieds but I saw that you don't have one on your tail so I threw it out there.

[MongooseGA]

Originally Posted by Norm Faustino

Sorry not trying to go off topic or hijack here but I noticed you have no lip on your whale tail . I have one in great condition. I will take 300 bucks or a nice set of H4's. I am getting ready to put it on the classifieds but I saw that you don't have one on your tail so I threw it out there.

Thanks Norm.

I have the rubber in the garage. I took it off because it was pulling away from the tail. I took it off an found almost all of the metal inside rusted to dust.

So I gutted the metal/rust and have to figure out a way to reattach the tail. I'm not really sold on the way the complete tail looks on the car, so I'm not sure what I'll ultimately do with it.

Honestly, I think that aside from the rough edges and mounting holes on the rubber-less tail, I really like the subtle and less obtrusive look as it is. I've considered making a 'low profile' lip to go around the edge to give it a finished edge, but that's low priority at this point. I need to make sure it's mechanically safe and sound first.

[Trackrash]

ROW factory height should be at 27" to the bottom of the fender opening. At 27" your camber will be at zero. US height will be about 27 1/2" and your camber will be about 1/2 degree positive.

If you are tracking the car negative camber is a plus. Otherwise more than a 1/2 deg negative will cause rapid tire wear.

There are three ways to deal with the camber issue with a lowered car. Use a strut brace to jack the shock towers apart, raise the spindles, or have the struts de-cambered.

Before I started driving my car on the track I maintained close to zero camber in the front with a ride height around 25" in the front by jacking the shock towers apart with a strut brace. So what if the gaps between my fenders and hood were large. I had no problem with tire wear.

Funny how things change. Now days I want as much negative camber in front as possible. To help that I actually use my strut brace to pull the shock towers together. I don't commute in my car any more so the tire wear is not a problem.

[Trackrash]

Found this thread on ride height.
911 sc lowered ride height pics & measurements please

[stlrj]

Originally Posted by Trackrash

Found this thread on ride height.
911 sc lowered ride height pics & measurements please

Originally Posted by JQ911

^^^
I measured mine like this... 24.75"F and 24.25"R (top of fender to the ground).


On the 101 Projects, its like this (torsion bars to the ground)

What I found by applying the factory method for the ROW (Euro) measurements, the 108mm (4 1/4"), equates to 27"F and the 12mm rear becomes 25 1/2"R. This is the result of restoring my 87 Carrera back to factory European (ROW) specifications.

It makes one wonder if anyone has actually crawled under to take the actual torsion bar measurements or is it the inability to convert mm to inches that prevents us from using the factory method as it was intended?

Correct me if I'm wrong, but nowhere in the Porsche Spec Book have I been able to find Euro heights of 25"F and 25"R based on fender openings.

As far as I can tell, this is what ROW or Euro height should look like:


















Cheers,

Joe

[javadog]

You're not doing anything wrong. What people claim is "euro" height is nowhere near correct. The few that have bothered to measure it the right way are so astonished at the resulting height that they figure that there must be a typo in the factory numbers. A few brave souls have actually admitted that their cars drive better when raised to the correct height. Sadly, way too many people worry night and day about their car's "stance"... And nothing will likely change that.

JR

[Trackrash]

My experience has been that the factory method was nonsense. My measurements using it never were anywhere close to reality.

Bruce Anderson in his "Porsche 911 Performance Handbook" states " What most people consider 'Euro Spec' is actually lower than the true European specifications. The correct ride height will result in a measurement of about 25 inches when measured from the ground to the rear fender lip."

The 27" in the front may have something to do with bumper height regulations. Lowering the front to about 25 1/2" inches results in a more stable ride at the expense of less than optimal alignment specs and clearance issues.

[javadog]

There were some years that the height was raised on US cars but eventually there was parity. I have no problem with lowering a tall US 911 to Euro height but having been down both roads I wish people would accept that Euro height isn't what everybody says it is. If confuses a lot of people.

JR

[stlrj]

Originally Posted by Trackrash

The 27" in the front may have something to do with bumper height regulations. Lowering the front to about 25 1/2" inches results in a more stable ride at the expense of less than optimal alignment specs and clearance issues.

Bumper height regulations?

Back in 67 there were no bumper height regulations and yet the 108mm front measurement still remained the same up to the 89 3.2 Carrera. Seems the factory knew something when they designed the 911 around this universally accepted ride height that some would call "nonsense".

[javadog]

Originally Posted by stlrj

Bumper height regulations?

It was either bumper heights or headlamp heights, can't remember which. I used to know the years it came into effect and the year they returned to normal, but I don't recall now. Ironically, the rear got raised more than the front at one point.

JR

[stlrj]

Originally Posted by Trackrash

Lowering the front to about 25 1/2" inches results in a more stable ride at the expense of less than optimal alignment specs and clearance issues.

I just went through this issue on my project car, 87 Carrera with 200,000 miles, which I thought handled pretty good with the front end lowered to what is popularly considered euro height. But after restoring it to factory euro height, something amazing happened. Not only did the steering get lighter but the front tires no longer squeal like a rabid pig when I punch it on the freeway 180 degree onramp. The front end sticks like it never did before and I can honestly say I have power steering regardless of how my non assisted rack looks.

Why most feel that lowering results in better handling must be due to some overwhelming placebo effect just knowing of the lower center of gravity, extra negative camber, stiffer steering feel and last but not least, the "cool factor" 'cus they look so cool down low...and I'll be the first to agree, they do look pretty cool down low.

[Trackrash]

"nonsense".

To clarify, what I meant was the method, re, measuring from the center of the torsion bar, I found to be, for better words, not a reliable way to set the ride height. I have no argument with the original factory settings, just how to arrive at them.

Lowering the front to about 25 1/2" inches results in a more stable ride

Again to clarify, if the front of the 911 is slightly lower than the rear, and the alignment is adjusted appropriately, stability will be improved, due to less air being forced under the front bumper at speed. Again this is at the expense of ride quality and clearance issues.

Just trying to share my experiences.