HalV

There's a lot of talk on coil overs but not so much on sway bars. The search that I've done seem to indicate that H&R fronts are ok but the rears are too big. Many people think the RS rears are the right size. Any other thoughts or options?

crg53

I would talk to Steve Weiner @ Rennsport, he is the man. As far as size of the H&R ARB's, the diameter does not mean anything, it's the Torsional strength that important.

HalV

Thanks crg53! I wondered if it was an apples to apples comparison when we were talking about the H&R diameter versus the RS bars.

KaiB

Get the H&R set and stop worrying about it.

Run both on the outer holes.

Vandit

Do swaybars affect transition speed? Like helping the car change direction going through a fast slalom?

boxsey911

You have to consider the H&R as a package that works together. If you consider one at a time then indeed you may think the rear is too big. The same goes for the RS bars. Some might think the rear bar on its own is too small but again they work as a pair. They have more adjustability but are a lot more expensive.

KaiB

Wow, quite the question actually. Rather than google this, I'll take a swing and hope someone sets me straight.

Sway bars couple weight, stiffer bar will help transfer more weight to the outside, however, the spring is the part of the suspension which controls the rate at which this occurs.

Weight transfer will occur regardless, however the stiffer the spring, the more rapid the occurance.

All other things being equal and on a properly setup car, I would say that the spring rate affects transition more than a sway bar would.

I tend to think of sway bars as a device (if everything else is done right) which helps steady state conditions more than dynamic ones...but...the suspension is a package and all components play a role in virtually all conditions.

Cogito_Ergo_Zoom

Here, let me help clear this up for you, courtesy of the Sauber F1 team:

HalV

That makes sense! Thanks Boxsey!

HalV

Sorry, Kai, I over analyze everything.

Thanks for the info!

KaiB

You and me both...just ask Stevie W. As a matter of fact, we were discussing the H&R bars on 964 just the other day.

We both feel that unless the owner/driver has a specific need to spend more money, the H&R is a perfect bar for our cars.

I've run them on the dual purpose build (Claudia V1.1) with PSS10s, pushing the car very close to its limits and then on the full out race build.

Never gave a second thought to the bars, they work!

DWS964

I'm curious if anyone has quantified the stiffness of the various bars - stock 18, 20, 21, RS at each hole, HR at each hole. For the same material, I recall the stiffness is a function of the diameter^2 or D^4 or something like that, so a change in diameter of 1mm is a much bigger difference than changing the length of the lever (inner to outer holes)
Another guy (engineer...) who over analyzes everything.
I noticed a difference going from a 18mm to a 20mm on my 90 C4.

HalV

Please excuse my ignorance but does replacing stock sway bars with H&R sway bars require a realignment?

August West

In looking at the H&R website, it appears that there's no distinction made between the C2 chassis and the C4 chassis...seems like there would be a difference unless that's where the two-hole adjustability comes into play.

Has anyone put these on a C4?

boxsey911

Changing bars or the droplinks won't affect the current alignment. BTW you'll want both sides jacked up to remove the tension when changing them out and you'll find the front one a particular pain to remove/install (not much room in there).