| Author | Message | ||
| Rob Schermerhorn (Rexrcr)
Member Username: Rexrcr Post Number: 833 Registered: 11-2002 |
0.25 mm shim, 0.50 mm equates to 1.0 mm diameter.  Rob | ||
| Phil Hughes (Ferrarifixer)
Junior Member Username: Ferrarifixer Post Number: 228 Registered: 7-2003 |
Your anti roll bars work best if they're tight enough to support their own weight, but loose enough to turn easily by hand when disconnected both ends. A dry teflon spray is best to lube them, if anything. Grease will turn to an abrasive paste very quickly. | ||
| lou staller (Lou_staller)
Junior Member Username: Lou_staller Post Number: 73 Registered: 12-2002 |
Mitch & MIke, I think you're both right. You're both telling me which ever size I buy, get them to 18mm either by hone or shims. I'll take your suggestions and end up with 18mm bushings. Thanks... | ||
| Mark Eberhardt (Me_k)
Member Username: Me_k Post Number: 757 Registered: 5-2002 |
I think I'd try the 17.5s, but use a flapper wheel on a die grinder to hone them out closer to 18..I don't think you'll want them that tight. | ||
| Mitch Alsup (Mitch_alsup)
Intermediate Member Username: Mitch_alsup Post Number: 1171 Registered: 4-2002 |
"I'm about to order new Polygraphite bushings and they offer them in .5 mm increments except for 18mm! So I think I'll order 17.5mm rather then 19mm. I think a tight fit will be better then a loose one." I might be inclined to order the 19mm bushinigs and order some 0.5 mm teflon sheet and cut to fit. | ||
| lou staller (Lou_staller)
Junior Member Username: Lou_staller Post Number: 72 Registered: 12-2002 |
Steve, I sanded some paint off of both bars and re-mic'd and came up with 18mm for both bars. So, I think your theory is correct as they sure aren't a machined piece. They're just a bent piece of tubular steel. (I know, I'm simplifing it.) The reason I'm being a bit anal about the size is I'm about to order new Polygraphite bushings and they offer them in .5 mm increments except for 18mm! So I think I'll order 17.5mm rather then 19mm. I think a tight fit will be better then a loose one. After all that's the purpose of the new bushings. Thanks for your input. | ||
| Steve Magnusson (91tr)
Intermediate Member Username: 91tr Post Number: 2149 Registered: 1-2001 |
I believe the Bs (and maybe the GT4s) had smaller rear bars (and in more than 1 size over their evolution) so those are different front/rear, but the Ss had the bigger/biggest rear roll bar from the start. I wouldn't get too fussy about the diameter measurement (IIRC the main body of the bars wasn't super-precision machined) -- could be in this case "18 mm" means about anything between 17 mm and 19 mm  | ||
| lou staller (Lou_staller)
Junior Member Username: Lou_staller Post Number: 70 Registered: 12-2002 |
Steve, I thought I read something of the sort here on F-Chat. I remember reading that the 308's had 3 different size sway bars and for some reason I thought I read that the front is different then the rear because of the weight distribution. Or maybe I was thinking about my own weight distribution! Anyway, I'm glad you confirmed there's at least 1 other car with equal sized sway bars. I'm still going to get to the bare metal and re-mic. Thanks | ||
| Steve Magnusson (91tr)
Intermediate Member Username: 91tr Post Number: 2148 Registered: 1-2001 |
lou -- I can confirm my ex-308GTS also had 18mm diameter roll bars at both the front and rear. Where are you getting the "19mm impression" from? | ||
| lou staller (Lou_staller)
Junior Member Username: Lou_staller Post Number: 69 Registered: 12-2002 |
Rob, Thanks for your input and tremendous degree of knowledge. Before I go through all that measuring, I think I'll first remove some paint, get down to bare metal them mic them again. But I'm still curious if anyone else might have the same size sway bars on the front and back. (Just in case I do.) | ||
| Rob Schermerhorn (Rexrcr)
Member Username: Rexrcr Post Number: 830 Registered: 11-2002 |
. | ||
| Rob Schermerhorn (Rexrcr)
Member Username: Rexrcr Post Number: 829 Registered: 11-2002 |
Diameter is only one characteristic which determines the spring rate of an anti-roll bar. Diameter, whether solid or hollow (if hollow: wall thickness) length of the torsion spring, length of the lever arms (from the center of the spring to the center of the link mount hole) are all the properties. Factor in the motion ratio (distance from inner control arm pivot to outer pivot or ball joint, divided by distance from inner pivot to ARB drop link mount), then this yields the spring rate the tire "sees". So more than likely, the front and rear bars have different rates. If you want to know your rates, measure the other data points and post them, I'll run the numbers if you wish. | ||
| lou staller (Lou_staller)
Junior Member Username: Lou_staller Post Number: 68 Registered: 12-2002 |
I really don't want to start a whole thing again but, while measuring the sway bars on my car I found they both measure 18mm. My car is a 1984 308 QV GTS. For some reason I find it weird that both sway bars are the same size. I was under the impression that one end was to be 18mm and the other 19mm. Am I spitting hairs here or what? Anyone else have the same size sway bars on their QV? |