arbeitm

Christmas has been good this year and I'm thinking I may use some of the gifts I received to get some new shocks and torsion bars.

I've done some searching and have tentatively decided on this:

Bilstein Sport shocks - front and rear
22mm front / 29mm rear torsion bars

Eventually I'll fine tune with sway bars.

Car is mostly used for autocross. However still drives on the street to events plus pleasure driving. And I'd like to do one or two DE's this year. (Haven't yet.)

I currently have the boge front struts (black) and orange????? rear shocks.

Any opinions?

john d 81SC

I believe the optimum shock set up is the Bilstein HD's for the front and the Sports for the rear. Don't know about the the torsion bars, though.

theiceman

I did sports all round and love them ..

Conekiller

I use mine for autox and DE also, my set up is 23 and 31 torsion bars, and custom valved bilsteins.

Edward

Hi Matt,

You've been doing your homework
Yes, for the purposes you've outlined, 22/29 with Bil Sports is an excellent choice, IMHO. If you want even better with only a modest difference in cost, find a set of used bilsteins, sport or not as it doesn't matter, then have Bilstein custom valve them to your car weight and spring choice. From eveyone I've talked to that had their shocks customed valved, it makes a noticible improvement (something I gotta do eventually, at least on my rears as it's easy and won't necessitate my having to rebalance/realign the car). I mention this to you since you haven't "done" anything yet, so it's easier/cheaper to do now than do later.

Eventually, you can go either the stock/easy upgrade with 22mm/21mm Carrera sways, or get more fancy/pricey and go to adjustables. Enjoy ...your car will be transformed!

Edward

arbeitm

Thanks Edward.

Couple questions on the custom valved shocks though.

What would the difference be from the sport shocks....stiffer? Are you recommending that because with the torsion bars I've selected, even the sport shocks aren't quite enough?

Any idea on what it costs to do that and where to get it done? (I'm assuming you send them back to Bilstein, similar to Koni's procedure.)

earlyapex

You can buy the shocks custom valved from Rennsport Systems, a Rennlist sponsor. Steve Weiner can give you advice on torsion bars and sway bars. It's nice to get everything together as it must all work together as a system in the end. Do you have stock bushings?

arbeitm

I'll check them out but I have a feeling they will blow my budget and I'm going to have to stick with the Sports.

I was planning on doing shocks and torsion bars at the same time. And then replacing the sway bars after I saw how it was.

I do have stock bushings. I was looking at the Weltmeister replacements and thinking of going that route. I used them on my 944 and was happy with them. I think derilin will be too much money.

racer

Custom valving will cost more. It will be worth it since it will better match the new torsion bar rates.

Cry a lot now(once) or a cry a little, a lot more frequently. No point in doing this work twice. Determine how the car will be used, if AX, consult rule books.. nothing worse then finding out new TB's put you in a Modified class, for example. Then get the best parts you can afford. You really don't want to rip all the "new" stuff out in 3-4 years do you?

Don't overlook nice new quality bushings either.

If/When you replace the sways be sure to have the rear bar mounts strengthened as they are a weak point.

Given that it looks like your 911 is a Targa, and you don't have a cage or other chassis stiffening componenets, i wouldn't go much stiffer on the rear torsion bars. Maybe even only a 28mm rear.

911's can handle great. What size rims/tires will you be running. Tires are, after all, the only part of your car to touch the road ??

Make sure you get the car lowered, corner balanced and aligned to take advantage of the new parts.

arbeitm

I'll look into those custom valved shocks.

Springs are allowed to be upgraded in my regions rule book. Any suspension part may be changed so long as it uses stock mounting points.

So you think I should go 28mm the highest?

My street wheels are 205/225 on 7/8 ROH wheels.

My autox wheels are the original fuchs 6/7 and I planning to get 225 track tires all around. (They don't seem to make them in 205's for the front in the Kumhos I'm looking at).

racer

I wouldn't recommend a 225 on a 6" wheel. Most tire manufacturers prefer a 7-8" rim for a 225 width tire.

I'm not saying a 29mm rear bar won't work. A popular combination I have seen over the years is 22mm front and 28mm rear. The effective "spring rate" difference between 28 and 29 isn't too much. It was just a thought.

Steve Wiener (sp) of Rennsport (a sponsor) is an excellent resource when it comes to suspension tuning. While his suggestions may not always be the lest expensive, they are worth asking about. Lots of folks out here have asked him these questions before.

You might consider putting the AX tires on the 7/8 inch rims and running 225/50 front and 245/45 rear, assuming the offsets are "correct" so that fender rubbing, particularly in the front, can be minimized. Then use the 6/7 for the street - your call though. Just a thought.

Which Khumos were you looking at. For DE/AX I enjoyed the Victoracers (205/55, 225/50 or 245/45 sizes). I know others like the V710s, but well, you might want to get used to 1) driving a 911 and 2) really learning to drive a 911 before going to the REALLY sticky tires

If your car doesn't have them, don't over look turbo tie rods and new ball joints. If lowering the car, consider a steering rack "spacer" of some kind to help eliminate bump steer. This will become more apparent on bad roads when using wider tires.

earlyapex

Looks like some heavy soul searching is due. Your car is specifically used for fun so I would keep it that way. A targa is the wrong platform for a TTOD AX car anyway. I would go for a compromise suspension setup that doesn't brake the bank. You can get away with not re-valving the shocks given the size torsion bars you are using. Get this done when this fits the budget and more importantly when your shocks are keeping you from improving your times. There is a learning curve associated with driving a 911 quickly. Shocks and torsion bars are a good place to start. If you can, spend for the good stuff early one so you don't have to do it a second time later on. Many of us have been there. This is primarily due to not having a good grasp of what we wanted the car to end up as. I've redone my SC several times, each time a bit more track oriented than the previous effort. It's now a track only GT class car and I still have the motor to do.

You'll have a great time with your car. Enjoy!

Edward

Hi Matt,

You could certainly buy revalved shocks form any tuner, but they will typically charge you extra for handling the transaction; Bilstein will do them for you the cheapest. The guy's name is Jack French. Great guy to talk to ...about $65/shock IIRC: you ship em; they return em. And "what you get" is a damping rate that is more closely matched to our specific T-bar selection and car weight. Off-the-shelf Sports certainly are good, but any OTC shock is "tuned" for a range of spring rates/conditions. Getting a shock custom valved to *your* car's specifics is simply fine tuning the suspension such that the components all work together better as a "system." When I looked into it, the damping rates were significantly higher than what came stock on Sports. Keep in mind that doesn't mean stiffer; to the contrary that means better controlled body motions. I'll be going there soon, but talk to anyone who has done it and they'll attest that it is worth it ...especially since the price (if you haven't installed anything yet) is very modest.

You'll get lots of advice on t-bar selection, and I can't speak for a targa, never having owned one myself. But if you decide to go with a 28mm rear, I'd go with a 21mm front; otherwise, stick with the 29 rear if you want the 22 front. I had the 22/28 combo and, while not bad, I personally prefer less understeer.

And yes, absolutely replace the springplate bushings while you're in there. You definitely don't want to spend all that time/money on good components, setting ride height/corner balance, then alignment only to compromise in the bushing department. I just isn't worth it IMHO ...replace them and you're good for another long time w/o ever having to deal with them again. Lots have gone with Elephant Racing's PolyBronze bushings with great success/satisfaction. FWIW, I decided on going with Poly Graphite (NOT the same as Poly Urethane) to trim cost and ease my installation. So far, I love them! ...no squeaks, firm, installation was a breeze, really great on the track.

As for wheels, certainly 7/8 would be superb, but as 8s are pricey, I'd go with 7s all around (you could pick up a pair of 7x16s cheap any day of the week) and stick with 205/225s. The extra 1" of rim in the front will definitely spread out the tread better than the wimpy 6-incher.

And yeah, budget. I know all about this one!! If you can't do all the suspension goodies now, I'd personally wait/save until you can. Believe me, it's cheaper in the long run, and you get a better end result. You can always do rims and sways later, but the T-bars/shocks/bushings really ought to be done all at once or you'll just be paying more do do it again ...IMHO of course. Hope this helps you.

Edward

racer

At the risk of sounding completely blasphemous... does the car *need* shocks right now?

Since you are moving from a 944 to a 911, there are some certain handling characteristics you will need/want to become comfortable with. It may be worth it to do nothing to the car at this moment in time. Simply learn to drive it and drive it well. Get used to it, and then focus on what you would like to improve or change.

I had a 914 on and of for about 15 years before I purchased my SC coupe. At time of purschase it still had all stock rubber bushings but a replacement set of adj Konis. I spent a solid 1-2 seasons with the car as it was. It really taught me how to control the car. Dealing with dive, sqaut and yaw was quite a challenge, but at the same time, it allowed me the time to be familiar with the car and really look into what I wanted to change. In the end, I changed shocks (custom valved bilsteins) torsion bars (23/30) sways (22f/r)turbo tie rods, steering rack adj, ball joints, 8/9 x16s with 225/245s, lowered, aligned and cornerbalanced, and the car was amazingly better. Had I not spent the time learning the "base" car, I would not have appreciated the improvements, nor had a firm feel for how much the performance envelope was expanded by these upgrades.

In theory, if the shocks are still "good", simply getting a performance alignment, lowering (if needed, you don't mention the current ride height), corner balancing and a good set of tires.

arbeitm

Thanks for all the advice. Racer...not do any upgrades???...that is blasphemous. Actually I have been contemplating the same thing. I did want to get a couple of autoxes under my belt with everything stock just to get a feel of how the car is to start. This way I can get an idea if my upgrades are exactly what I want. I doubt I'm patient enough as you to leave it that way for 1-2 seasons.

I have a few months to think about it. I just wanted to start collecting information now.