Solid, or much firmer, suspension bushings - advice and pointers

Hi Folks,

I think I'd like to get rid of the squish in my car - the rubber bushings that allow large amounts of deflection. Aside from feeling it, i was startled ot see just how much my alignment settings distort when i place modest pressure on them with a pry bar, with an alignment system active. Yikes!

The main ones I know are the pivot bush and the puck in each of the four control arms.

1. any others i should concern myself with, when applying Pareto's rule?
2. suggestions
3. where to find
4. installation tips


I have GT3 control arms front and stock rear. 986S

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

Quote
grant
Hi Folks,

I think I'd like to get rid of the squish in my car - the rubber bushings that allow large amounts of deflection. Aside from feeling it, i was startled ot see just how much my alignment settings distort when i place modest pressure on them with a pry bar, with an alignment system active. Yikes!

The main ones I know are the pivot bush and the puck in each of the four control arms.

1. any others i should concern myself with, when applying Pareto's rule?
2. suggestions
3. where to find
4. installation tips


I have GT3 control arms front and stock rear. 986S

Grant

That "squish" makes for a tolerable ride. A ride with acceptable levels of noise vibration and harshness. And even with the squishiness the car delivers very good handling, steering, and road feel. Handling, steering, and road feel other car makers would kill for.

My thinking is if you want to firm the handling up you should go all the way and replace all rubber bushings/etc with firmer ones ideally ones that maintain the same relationship of squishiness with each other (albeit with much less squishiness) as the stock ones have with one another.

If some are firm and others left stock the car's handling, steering and road manners might be negatively affected.

You still then have the alignment to sort out. The factory alignment settings take into account the give of the stock suspension. The car's alignment on the rack changes when it is on the road but in a known way. With new/firmer bushings installed the alignment will change less so some alignment settings might need tweaking to optimize the alignment and get the car's handling, steering and road manners back to where they were before the new bushings were installed.

I know where i want my settings, i just need them to stay put :-)

Its not that easy to find harder, rubber bushings. Also, most input I have received so far is that I'll likely spend a lot of time and/or money and still be unhappy unless I go to solid for at least the 8 I mentioned... but i'm open to those who have experience.

I drove a similarly set up car with solid bushings the other day (on track) and all I can say is ...wow. A revelation in both grip and feedback.

Historically, i have heard that urethane bushings, for example, don't last well when used on the street, because they effectively dent and permanently deform rather than give and return, like (young) rubber. Several race prep mechanics I've spoken with say that today's solid units, at least in Porsches, hold up well even for cars that commute to and from the track, like mine.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

The ones I have are from European Parts Solutions (EPS), e.g.

[www.europeanpartssolution.com]
[www.europeanpartssolution.com]

I got them from Vertex Auto, where they are cheaper than the manufacturer's website.

It makes for a nice upgrade, with sportier, more responsive handling. I haven't had them for long enough to say anything about their longevity but their website says "permanent solution, will never go bad" and "full 5-year warranty". Is it just me or is that a mixed message?

tell me more about the handling, and a little about the ride.

Grant

gee-lenahan-at-gee-mail-dot-com

The handling feels more immediate and direct. In terms of handling I see no downside. In terms of ride quality, the F&R strut tower braces I have make the ride noticeably harsher but I really haven't noticed any significant difference in ride quality with the poly bushings.

Those have a fairly significant impact on handling (reducing movement f<->r), btu little impact on vertical impact.

I suspect the pivots make it harder, but they reduce toe change. Amazing how much it moves when i pried on them, with an alignment system connected.

Actually, thinking about it, i should not have been so amazed :-)

Grant

gee-lenahan-at-gee-mail-dot-com