jungleboy

Quick question to piggy back... the H&R folks tell me the stock drop links would be fine T OR F? I'll do some more research in the archives in the meantime.

Bill Verburg

I had TRG 25/22 bars am much happier w/ RS 23/20 besides the stiffness the bigger bars present more of an interference problem when used w/ the vacuum boost system on a 964/993

which drops you need depends on ride height, at RoW M030 height to US ride height, 144/127mm up to US height 174/157mm the short stock links are fine. As you go lower there is going to be interference w/ the suspension arms unless the curved RS links are used.

993RS drops, front on top, rear below


the rear is where there is the most trouble
993RS drop, 993RS sway, TRG/H&R etc will be similar at this low ride height


At the higher ride heights the sway bar would be above the suspension arm

matt777

Hi Bill, what specifically was the difference in ride/handling between the two?

jungleboy

Bill thanks for the info, you are always helpful as usual!

Ditto -

Bill Verburg

In front the big bars have an interference issue w/ the brake vac booster.

In back the big bars are always on the softest setting which is still too stiff for street use.

DaveM993

I run Pss9's with the H&R sways and love the combo. I was a little worried about the car being "over barred", but NONE of my fears have come to pass. I have them on the stiff setting on the front and loose setting on the rear and the car is about a near neutral as I have experienced. If you are on a "bumpy" course you can feel the car not absorbing them as well.

But I am a satisifed customer.

Van1

In theory, doesn't stiff up front and loose in the rear exacerbate understeer?

Bill Verburg

yes

matt777

Thanks guys. I just threaded the front bar in last night after disassembling the drivers side. I haven't got the bushings in but things will be close as far as the vac booster goes. If you look at the size and stiffness of the bar (nearly double that of stock bars) I would doubt that the change in stiffness between the front and rear holes would be significant. I don't relish the the thought of having to change that front bar out but it's what I've got for the moment.

jungleboy

That's good to hear. Any issues with the interference that everyone's faced at all? Also, what's your final ride height that you've set? Thanks...

Interesting...

Mark in Baltimore

Oversteer in 993's is completely overrated. My car is set up with a bit of understeer, and it is very comfortable to drive at decent track speeds, all of which adds up to increased driver confidence. Initially, I, too, worried about running a stiff front and loose rear, but I simply couldn't argue with how the car felt and the great lap times I was getting.

TheOtherEric

+1. Whenever I set up for oversteer I end up regretting it. Praying to god every time you enter a high-speed sweeper (e.g. T1 at Mid-OH, Kink at RA) is simply not a fun way to drive. Maybe it's fun to rotate the car easily thru a tight corner, but dang those sweepers become scary.

Mark in Baltimore

Yeah, I hear you. It's the fast corners where you really need to keep your foot down in it. Some high speed understeer is perfect and much more desirable than brittle oversteer. For the low speed corners where I get understeer, I try hard trail braking so that the car rotates, thus ameliorating the push.

jungleboy

And a slight lift mid corner helps too

Bill Verburg

There are many factors that contribute to over/under steer
wheels
tires
tire pressures
suspension setup
weight
location of weight
springs
speed
etc.

Your basic suspension characteristics are determeined by the spring(actually wheel) rates and ratios f/r, suspension setup and then tweeked w/ sway bars and tire pressures
spring rates f/r
US factory M030 200/275 0.727
Row M030 150/300 0.5
993 RS 246/457 0.5375

the lower the # the more toward oversteer

the lower the grip ratio f/r the more toward understeer

the lower the sway bar ratio f/r the more toward understeer