Norm Peterson

Post #13,684 Nothing better to do, I guess. Norm

Yes, but I'm not at all sure what their current status is in the USA. For a while, they were pretty heavily involved with the 5th generation Camaro (that car being based on a chassis developed by GM's Australian subsidiary). That ended rather abruptly and at least one of Pedders' USA principals is off running his own Camaro-oriented business these days. Have you even found a link to any USA operation that displays something other than "HTTP 404 Not Found"? Norm

At best, the 225 is only an approximate maximum section width (taken at the sidewalls) measurement . . . and when the tire is specifically mounted on its "measuring width" wheel. Every inch wider than "measuring" adds about 0.4" to the section width, which in the case of 225's will make them appear more like 235's. And the actual measurement varies among mfrs, even among different tire models from the same mfr. Could easily range between 3% wider and 3% narrower than nominal. That won't officially buy you any additional load capacity, at least not according to the T&RA. But you have gained a little inside volume, which does loosely correspond to load capacity (at any given pressure). Norm

I spent something like 40 years doing structural analysis including work involving structural vibrations. So I have a very good idea about what's going on with a STB of any sort (they aren't very complicated things). You're trying to convince me and anybody else who stumbles across this thread that observations made by a person or persons of unknown engineering aptitude are worth more than a clear understanding of a few pretty basic engineering principles. Never mind that that sort of observation may well be biased by not wanting to face the prospect of having wasted money on a STB that doesn't live up to all of its advertising copy. Sorry, but that's almost down there with trying to convince me that 2 + 2 = 5. What really bothers me here is the attitude in the above quote where the value of engineering knowledge is discredited. Feel free to find a different engineering opinion and post the explanation that goes with it. I'll at least listen. Norm

A structural brace cannot effectively stiffen a bushing without connecting the two things [that the bushing is trying to provide some isolation between] directly to each other. I suppose if the chassis was truly in the 'wet noodle' category, you'd still gain something. But if it was that bad, you still wouldn't be adding a RSTB for performance reasons unless just keeping the thing in service is considered a performance improvement. Norm

STBs will change the structural vibration frequencies and modeshapes, which is something you'd likely feel without being able to describe very well. Locally, there is some added stiffness, which is what chases some vibrations off to other places and/or different frequencies that you don't feel as much. The car would then be apt to feel more 'solid' without being significantly stiffer overall (which is mostly what matters for handling - particularly chassis torsional stiffness). Norm retired structural guy

If the adjusters aren't difficult to get to, it's maybe a five minute job to reset them on the occasions where your passenger(s) might not have as much tolerance for a firm-ish ride as you. You can fab up a much better adjustment tool from a short length of 1" x 1/8" steel strip than the plastic knob thing that Koni ships with them. Norm

Why? Struts don't affect ride height statically and only somewhat dynamically. Do you have or are you planning to get springs that are THAT MUCH stiffer? Norm

I'm not afraid of cutting springs (BTDT), but I'd want to know a bit more abut the spring configuration first. Like, is either end "squared and ground" and the other "tangential"? Or do you have to cut whole coils because of top and bottom seating requirements? I'd also much rather start with a spring intended for a heavier vehicle, or at least one rated for a heavier load. Norm

Replace all four corners. Dialing the rear setting up a little from full soft should quiet the rear jounce movement down - Koni "yellows" are single-adjustable on the rebound side which is what you need to keep spring extension under control. You might then wish to up the front damping a little as well if the tail of the car starts feeling "loose" during "enthusiastic maneuvers", but sneak up on any need to do this slowly. Norm

Fred Puhn's softcover book "How To Make Your Car Handle" is as good a place as I can think of to start. Once you can put a few numbers on things, it gets easier. LReg - do you suppose that Civic driver is using a combination of power + braking to balance out the longitudinal forces up front while adding some out back to get that end to run at more slip angle? Norm

I wouldn't even install/re-install OE springs on struts that had 120k on them. Not even if that was 120k in km and not miles. Norm

Evidently the gas pressure in the Bils is high enough to take load equal to 1" of spring compression off of the springs. 1" sounds a bit high though - half an inch is more what I recall being mentioned for gas pressure shocks in general. Question - was this measurement taken before or after driving the car a little? (When you first drop your car off of the jack, the suspension normally does not find its static position because that requires a bit of lateral tire scrub from the droop position. Until you roll the car some, lateral tire grip is actually holding the car up.) If there is no special position for both ends of the spring to be in, I don't see any reason that you'd need to cut in half coil increments. You might be able to estimate about how much based on the coil spacing with the car's load being fully on the wheels. IOW, if the loaded coil spacing is 3" center to center of adcacent coils and you need to lose 1", you'd be cutting about 1/3 coil. About 10% change is about the smallest that you'd notice. It's also possible that the springs didn't get seated quite right, so check that (and fix if necessary) as well before doing any cutting. Norm