lowering car with new Bilsteins

[my911cab]

I plan on putting on new bilstein sports on my carrera. I heard that it is recommended to lower the car to euro specs when you do this or the car will sit too high. true? false?

[KFC911]

The new Bilsteins may indeed raise your car's height a bit initially, but it's still your choice whether to return it to "stock" or "euro" height.

[Greek55]

If you lower your car to Euro specs, it will handle better and, in my opinion, look better. Downside is scraping the parking lot stops, bottom of inclined driveways and some speed bumps.

[KFC911]

I agree, I like my car at euro specs, but it's a choice, and not related to using Bilsteins (which raised my car just a tad).

[ulrichd]

Give it a week or so after the shock install to let them settle. My 78SC gained 1/2" in ride height after I installed Bilstein HDs and dropped a 1/4" within a week.

Ulrich

[my911cab]

Thanks for the replies. So just to clarify. Whether or not I stick with the us height or lower to the Euro spec height I may need to lower it depending on how much the shocks settle. I am leaning towards the euro spec height but was a little shocked how much it costs to get the car lowered. I think that I was quoted about a 1000.00

[Greek55]

It is a personal preferece. You can take a look at cars lowered and not lowered on this forum and decide. Also it depends on your streets. My car did handle better.
If the $1,000 includes the shocks, lowered, aligned and corner balanced, thats about right. If that is just to lower it, you can find a much better deal.

[ulrichd]

1K seems high, seems I have seen $500-600 posts here before. Either way it's a lot, but we are dealing with something that requires a great deal of patience and in my case, endless repeats. Even with using the springplate angle calculator, triangulating the fronts and backs, I would still wind up being way off. I actually once put a wrench through a sheetrock wall in frustration over this process.
Here's a great link showing the process:
Memorial day project

Back to your original question: do the shocks first, let them settle, then do the ride height.

Ulrich

[my911cab]

Another newbie question. I'm guessing that a full tank of gas adds a lot of weight. Would the adjustment be made with a full tank? The quote that I got was just for lowering and aligning.

[KFC911]

Originally Posted by my911cab

Thanks for the replies. So just to clarify. Whether or not I stick with the us height or lower to the Euro spec height I may need to lower it depending on how much the shocks settle. I am leaning towards the euro spec height but was a little shocked how much it costs to get the car lowered. I think that I was quoted about a 1000.00

Yes, you are correct on the first part...after the new shocks settle in, you may need to readjust to either US or euro height (your preference). In my case, I lowered my own car (along with a total suspension rebuild/refresh), but it can be very time consuming...and at shop rates, he's probably giving you a "high estimate". Are you sure he's not giving you a quote for a "corner balance" also? That can be very tedious and time consuming too, and that's where weight (driver's and gas) come into play...don't worry about it in your case. Just to clarify, lowering the front is a breeze, but for the rear, it will require "reindexing" the torsion bars (possibly more than once, if they're not lucky/good), and if your car has never been apart, that itself can be a bear. Good luck!

[hkiang1]

At the same time you change the shocks/struts, you will want to do an alignment. If you need an alignment, you might as well have a shop lower the car and do a corner balance (to make certain that the car will be riding at the same height at one side and the other) first. When having the car lowered and corner balanced, it is typical practice to have half a tank of gas. And the whole procedure shouldn't cost more than a few hundred dollars. Lowering the back is a bit of a pain but lowering the front is a 5 minute afair.

[KFC911]

Originally Posted by hkiang1

At the same time you change the shocks/struts, you will want to do an alignment. If you need an alignment, you might as well have a shop lower the car and do a corner balance (to make certain that the car will be riding at the same height at one side and the other) first. When having the car lowered and corner balanced, it is typical practice to have half a tank of gas. And the whole procedure shouldn't cost more than a few hundred dollars. Lowering the back is a bit of a pain but lowering the front is a 5 minute afair.

I doubt seriously that you will find a shop that will lower, corner balance and properly align a 911 for a few hundred $ at shop rates. Those three items are independent of each other and each in itself can be VERY time consuming. Simply changing the shocks will not necessarily require an alignment (unless the ride height changes VERY significantly). I do agree, that one should both lower and corner balance at the same time (corner balance is overkill for a street car imo) if you desire both.

[hkiang1]

I just called Roger Krause Racing over here in the Bay Area, California, (where I did my own car, and a favorite place of many Golden Gate Chapter PCA members) and they quoted 3.1 hours to change the shocks and struts plus $300-$380 to lower, corner balance and align for a total of $6-700. My recollection did not include the price of the shocks/struts install. My apologies.

[wnsgc]

My 85 Carrera was sitting high to begin with, but once I changed the shocks/strut inserts from the original boges to bilsteins, my car was ready for the Paris-Dakar rally... It's sitting up way to high now and yes, the difference between a full tank of gas and almost empty is around 1/4 inch.

I'm in the process of having the car lowered (to euro ride height) and while I'm at it, the torsion bars are being replaced (21mm on the front and 30mm on the rear), as are the factory a-arm and rear spring bushings (going with Weltmeister poly-graphite) and installing turbo tie-rods.

Hopefully when this is done, I'll be driving a meaner looking car that handles better than when new.

Since it's been sitting high, I have noticed the car drifting when going into a turn at high speed.

[Greek55]

I had a local prosche wrench put on sport shocks, lower, corner balance and align and it cost me $1,050. That includes the sport shocks. Just lowering and corner balancing was $300. A shop that does this day in and day out is not going to spend more than 4 hours to do all of this.

[KFC911]

Originally Posted by Greek55

I had a local prosche wrench put on sport shocks, lower, corner balance and align and it cost me $1,050. That includes the sport shocks. Just lowering and corner balancing was $300. A shop that does this day in and day out is not going to spend more than 4 hours to do all of this.

If I could get my car corner balanced and aligned (already lowered) for $300, I'd do it in a heartbeat. I was under the impression it was much more than that. My suspension is "fresh", and I've got poly-bronze spring plate bearings so reindexing t-bars should be "easy" if required. Thanks, I'm going to investigate...btw, where are you located?

[Greek55]

Originally Posted by KC911

If I could get my car corner balanced and aligned (already lowered) for $300, I'd do it in a heartbeat. I was under the impression it was much more than that. My suspension is "fresh", and I've got poly-bronze spring plate bearings so reindexing t-bars should be "easy" if required. Thanks, I'm going to investigate...btw, where are you located?

I am in Columbia S.C. There is a company in Greenville, S.C. called Pro-Tec that will corner balance and align for $225.00. They do mostly Porsche's. For the price you are being quoted it would be worth the drive.
I have done a good bit to my suspension, but corner balancing and aligning made the most noticable difference.

[KFC911]

Hmm...maybe a road trip is in order...thanks!