Who's lowered? How low? Using raised spindles or no?
 

Guys,

I am in a bit of a bind right now as I am completely rebuilding my 911 and have come to the suspension. I am wanting to go lower. Probably a bit lower than euro height especially as I have the euro meister 17" wheels.

Question is --- do I really need to spend an additional $400 on raising spindles and $400 for the race bump steer kit for a street car? Or are there folks out there that have lowered without raising the spindles and have good performance? I will be replacong/upgrading every bushing and component of the suspension... and this is an $800 that maybe I don't need to spend.... I will be getting 22/28 torsions, by the way.

Thank you in advance --- and pictures of your car, description of your suspension would be beyond appreciated.

Best,
Paul

"Probably a bit lower than euro height especially as I have the euro meister 17" wheels."


Why lower than Euro height because you have 17" wheels? Are you running super low profile tires?

I'm on 23/31 bars with adjustable Hotbits race dampers and sitting about 24.25 front and 23 7/8 rear. I have only a rack spacer kit and bumper steer is NOT a major issue. All said, i'm planning to reduce the front bar to 21 to loosen up the rear end a bit.


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There are two issues with lowering. Limited suspension travel and bump steer.

Lowering will decrease how far the suspension can compress. You are going to feel it hit the bump stops. Raising the spindles compensates for this. Ideally your struts should be matched to the torsion bars.

Lowering also induces bump steer because it changes the A-arm geometry relative to the steering rack. If you were tracking the car this would be a greater concern. The side effect of uncorrected geometry is you will feel the steering wheel snap sharply left/right at times (going over a speed bump).

You may also get tire rub so you could have to roll your front fenders.

You will certainly need to get the car re-aligned afterwards.

When I bought my car it was lowered to Euro height with no compensation. I completely refreshed the suspension and I'm below Euro height now. I much prefer the handling now over the way it was before but it's hard to make a good apples/apples comparison when you have worn bushings and struts as a starting point.

My advice for a street car is to not worry about the look, replace the worn out bits in the suspension, match your struts to your torsion bars and call it a day. You'll get better handling and better tire wear and spend a lot less money.

Paul,
In short, no you do not need to do either of those things. I ran the $20 rack spacer kit on my car for years, including about 100 track days and never really had an issue. As stated above, all the work you are already doing will make a massive difference in the feel of the car. For the street and Euroish height, you will be good without. Agree on rolling your fenders.

Since you asked, I'm currently running 22/30 torsions, custom valved Bilstein sports, RSR raised spindles w/ ER bump steer kit, smart racing ARBs, and a combination of elephant polybronze and spherical bushings. My car is an '88 and is lower than Euro height.

mat

Maybe a little too low ?
 

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My 87 been this way for two summers and would like to go back up a bit this winter, good project. I did raise the steering rack as much as possible with a calibrated stack of washers (easy). Nothing else done, never felt this "snap/bump steer" that others seem to mention. 22/29 Tbars and sport shocks all around. Ride is definitely firm but its a sports car. Front fender lips are shaved inside vs. rolled. Little more negative camber was needed also.

With stiffer torsion bars, the suspension is more resistant to travel, so the issues with lowering a car excessively (understeer, bumpstop bashing, and bumpsteer) will not be as apparent as a car with stock torsion bars. Also, using a smaller diameter, aftermarket steering wheel will enhance the feeling of bumpsteer. I use a 350mm Jackie Stewart signature Momo.

I rebuilt my suspension and initially kept stock torsion bars on it, I had driven it for 2 years and felt the suspension was plenty stiff. I used rubber bushings from Elephant Racing throughout and lowered the car about a half inch below Euro height. The car rode much nicer, a little too nice, the stiff original bushings were masking the softness of the stock torsion bars. The following year, for appearance purposes, I lowered the car a little more and that's when things turn to poop. It understeered very bad, crashed over bumps, and had very bad bump steer. I was still on stock torsion bars and had steering rack spacers.

Since then, I raised my spindles 30mm (max for 16" wheels) and added the adjustable tie rod ends. Made a world of difference. The front end is much more positive, it glides over bumps again, and has next to no bumpsteer.

With your 22mm front torsion bars, it will mask any issues, especially if you don't excessively lower your car. But if you are rebuilding, why not spend the money and make it right the first time?

What kind of struts do you have? If you have Boges, you can send them to these guys.
Tangerine Racing Suspension Services

They can raise the spindles up to 22mm and they bend the steering arm on the strut assembly so that you can use your stock tie rod ends. That is what the factory did on RSR's thru 935's. And it costs $359.95. I wish I knew about it before buying a set of Bilsteins and having them modified.

This. I went through mine, refreshed bushings as needed, raised the height set to provide reasonable travel. Still a bit lower than factory, so still have the bump steer rack spacers in. At 26.5 F and 25.75 R now, and the car rides and handles fantastic for street. Would it look good lowered a bit more? Maybe, but I've gotten used to it now, and won't change it, it drives too good the way it is.

I recall reading in one of Carroll Smith's books, "Before you decide to build your own car, first figure out what you will do better than March, Ralt, or McLaren"

My point is that Porsche likely spent gazillions getting to Euro Height. There are millions of permutations of camber, toe, castor, just in statics, then add in the rear and figure out what the dynamics are going to be.
Having the front start to go into a bit of roll steer, while the rear is not yet to that point is going to impact the way a car transitions into corners.

Porsche has already figured it out, so, my recommendation is to start at Euro height, get it cornerweighted and aligned.

Good luck,
chris

Low rider 911s handle like crap......if you want the "look" get a 63 Chebby Impala.

bull****

The stock suspension geometry is a compromise. It was decided upon for the best combination of handling, ride compliance, and cost to manufacture. If the stock suspension geometry was optimal, why did the factory lower it when building the the RSR from 1973 and on, or the early 935s? Porsche started raising spindles in 1973 when they built the RSR. If a car is properly lowered, it will handle well and ride nice.

No other chassis modifications to my SC besides 16x7/9 fuchs, factory Bilsteins, bump steer kit and rolled front fenders. Alignment came in wonderfully at the current height and the car handles well but not punishing. It was set up for long distance touring as it seems silly to me to beef up suspension on an open top car.

http://forums.pelicanparts.com/uploa...1473266436.jpg

In the world of suspension.. 1 " is a lot. I have noticed a great improvement in lowering a sports car 1" ( street car/non-Porsche )
Right now I am in the process of a new suspension system for the P car, will keep you all posted.

Thought,
The factory is in the bidness of making everyone happy. In the case of the good ole USofA that includes soccer moms who want a Porsche that drives like a mini van. I like my car raw, like the original 911's, little rough around the edges and crisp, everything soccer moms hate! Make it yours, have a plan and execute!

24 1/4" front and rear fender to ground.
Spindles raised 22mm. 22 and 30mm torsions.
Great on the track and smooth roads. Not so good on driveways and some of the crappy roads around here.
If you raise the spindles you will need the race bump steer kit. (and have it properly adjusted)
If you don't go below about 25", you probably don't need to raise the spindles.

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This is my 85 with Euromisters 17 inch wheels. Stock European ride height.

I would not want to go lower. I can actually get up a driveway or over a speed bump. I think it is perfect.

The Spec 911 racers here on the west coast go really low. So low the front tires are inside the lip of the fenders. They probably run 22/30mm t-bars, but still... FWIW, I've seen most of the class lowered this far down.

http://forums.pelicanparts.com/uploa...1473282018.jpg

The full range: dead stock to flat out full racer......
 

We have heard from a good selection of enthusiasts: Totally stock to full time flat out racing.

To get your car set up, you need to be really clear about what your goals, needs/wants are.
This has to be tempered by your budget and or mechanical skills.
Further, you need to keep in mind your local road conditions/ family transportation needs.

In truth, it is much easier to stay dead stock, or go unlimited budget flat out, no holds barred racing.

Compromise:????? the need for some reasonable tire mileage, ability to get into the average driveway, Drive, wet or dry, haul the family, so no outrageous NVH??? How serious are you about doing "well" at auto xing or track days.

I have been doing this for almost 50 years, with a hot rod MGA, a slightly tweeked 66 911, (bars, shocks, racing tires, outrageous exhaust), a rehabilitated, wrecked fairly sophisticated, (for the time) speedster - cost me $500 for a roller to put all of the hot rod parts in), a stock 914 with continual upgrades, (flares, S brakes 175 hp 2.4 expensive 4 cyl), a 77 Ferrari 308gtb with track suspension and absolutely killer brakes, and now, back to refreshing my dad's original 74 2.7.

Everybody has their own budget, priorities, preferences and their own experiences, which are not likely anywhere near what yours are.

So, this is where you need to go to a few very experienced sources, and I would talk to several.

If you are very honest with yourself and them regarding what you like, want, can afford, you are much more likely to get where you want to go.

There are many highly regarded experts with stellar reputations for being not only helpful with the appropriate products, but more importantly sincerely trying to guide you to get where you want to go.

Most of my recent Porsche business has been conducted with Chuck at Elephant Racing and I have no reservations whatsoever about recommending him to you.

Think about what you want, then give him a call.

keep us posted,
regards,
chris

No. Most run at least 33mm rear torsion bars and some run stiffer than that.