Optimal front sway for a 1.7 ? Options

[Literati914]

I believe, if I’m not mistaken, there was a 13mm front sway bar for the 912 cars.. and I was wondering if that wouldn’t be more appropriate for a 1.7L 914 rather than the stock oem 15mm. I’m not sure if anyone bothers with a ARB on a 1.7L, but the 13mm ones are fairly easy to come by, cause everyone upgrades to bigger. So that’s a plus. Thoughts?


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[horizontally-opposed]

Great discussion, and I've long wondered about adding a rear ARB.

Consensus when I added a front Weltmeister ARB and 140lb rear springs in the 1990s—hard won by a super active autocross and time trial community around the 914, presumably based on lap times + handling dynamics—seemed to be:

> Weltmeister front ARB, no rear ARB
> 140lb rear springs
> Konis (red for more street, yellow for more track)
> Lowered and aligned
> Widest rubber you can fit

I followed that recipe and also thought the car handled really well, both for autocross and for back roads. But this isn't 30 years ago, and I'm here to learn!

[Superhawk996]

I followed that recipe . . .

The only real problem is that what is good for autocross isn't always what you want for the street. AX tends to favor cars that are easy to rotate at low to moderate speeds. You very well find that ability to rotate isn't appreciated on a big highway cloverleaf sweeper taken at 2x or 3x posted speed. (IMG:style_emoticons/default/dry.gif)

Don't get me wrong, we all follow the recipe to a degree. The moral of the story, don't just follow blindly, tune to what suits you and know why you're doing it.

Following that AX recipe forces some ride degration with the 140# springs that might otherwise not be needed had we opted for a softer spring and a smallish rear bar.

Don't get me wrong, I largely followed the same recipie you laid out when I got started back in the early 90's with suspension and chassis tuning and didn't fully understand the tradeoffs I was making. Not everyone want's to go to all the time, expense, and trouble to to learn how tune. That's OK as long as they know they are making tradeoffs in the process. (IMG:style_emoticons/default/beerchug.gif)

[horizontally-opposed]

I followed that recipe . . .

The only real problem is that what is good for autocross isn't always what you want for the street. AX tends to favor cars that are easy to rotate at low to moderate speeds. You very well find that ability to rotate isn't appreciated on a big highway cloverleaf sweeper taken at 2x or 3x posted speed. (IMG:style_emoticons/default/dry.gif)

Don't get me wrong, we all follow the recipe to a degree. The moral of the story, don't just follow blindly, tune to what suits you and know why you're doing it.

Following that AX recipe forces some ride degration with the 140# springs that might otherwise not be needed had we opted for a softer spring and a smallish rear bar.

Don't get me wrong, I largely followed the same recipie you laid out when I got started back in the early 90's with suspension and chassis tuning and didn't fully understand the tradeoffs I was making. Not everyone want's to go to all the time, expense, and trouble to to learn how tune. That's OK as long as they know they are making tradeoffs in the process. (IMG:style_emoticons/default/beerchug.gif)

Yep, fully agreed re: what one needs for autocross vs street (or track). While I'm a big fan of autocross, the need to rotate the car to get it to turn in at low speeds doesn't always lead to good setup—or muscle memory!—for higher speeds on road or track.

Interestingly, the "no rear anti-roll bar on a fast 914" dictum of the 1980s/1990s should make the car less prone rotate—right? Of course, 140lb springs add roll stiffness at the rear, while front spring rates were often left alone (ish). Reminds me a bit of Porsche's approach with the 987.2 Boxster Spyder: They decreased the rear ARB, but upped rear spring rates by 50%! When you think about how well a regular 987 Boxster/S handles, that's a big "tweak." But it made for the best-handling 987.2 hands down—and that's saying something because all 987s were great! (IMG:style_emoticons/default/wub.gif)

My current setup—911T front torsions bars, 140lb rear springs, 22mm front ARB, no rear ARB, rubber bushings all around—worked well when the car had 80~ hp and still works well with 200~ hp. Everyone who tries the car raves about the handling, though I know it can be a bit better/sharper still. While I followed the advice of 914 autocrossers and track-day denizens when I was a teen, curious to listen to current thinking so many years later…as I will probably do my 914's suspension and brakes one more time. <I hope!> Currently eyeing KW dampers, different ARB(s), and an LSD along with 986 calipers front and rear. Spring rates seem about right. Don't want to go higher for the street…