Typically listed in lbs.......what does it mean?
What does about "about 400 lbs front and 650 lbs rear" vice "about 400 lbs front and 470 lbs rear" mean.
I think I know.....but just wanna make sure I know.
Thanks
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Typically listed in lbs.......what does it mean?
What does about "about 400 lbs front and 650 lbs rear" vice "about 400 lbs front and 470 lbs rear" mean.
I think I know.....but just wanna make sure I know.
Thanks
I believe that's lb/sq inch, but I could be wrong on that. Basically, it's how stiff the springs are. Springs serve to allow the shock to do its job - if they're not matched well (or perfectly), you get an oddly handling/riding suspension.
As far as front to rear spring rate theory and practice, that's way beyond me. Suffice to say that for the dynamics/characteristics of our cars, we have stiffer springs in the rear. 400 lbs would probably be a decent street setup for an E46. 650 would be pretty stiff, I'd imagine. I have 6-somethings on my MINI, and it's wayyyyyyy too stiff for the street.
One thing I learned is that when/if you buy coilovers and have them installed (or install them), test and check the spring rate. I bought from a VERY reputable suspension company (KW V2) only to find that the springs they sent me were progressive (not good for track) instead of linear and NOT the correct rates. Had I not tested them, I'd have found out mid-corner at the limit when the rate changes. Oooops!
All of these variables/uncertainties/areas of expertise are why I tend to trust the people who do real track setups even if a person isn't looking for a track setup: TC Kline, Turner, etc...
OK......so....about 400 lbs front and 470 lbs rear.....would be a decent setup then.
Do we have stock spring rate data for zhp springs?
I believe that's a much more complicated can of worms than you'd expect; I do not believe that there is one spring rate for all ZHPs. From what I can remember (I'll redo the research in a bit), the spring rate for your car takes into account all of the options it was ordered with; things like the H/K sound system, navi, auto vs 6MT, etc. all change the weight distribution & therefore what springs you got.
Somebody on E46F had compiled a lot of data from users on what springs they have on what models; I'll see if I can't dig that up.
I have no way to tell if that's a decent setup or not. I'd be more concerned with whether or not the springs were linear or progressive, first. Linear springs keep their rate throughout their travel; progressive are different depending on the load. Personally, I don't like that feel.
And I don't know the stock spring rates; 400 and 470 sounds pretty mild to me.
Ok, after digging a bit through E46F, I found one of my original responses to someone asking nearly the same question:
Also, from the pictures folks had posted of their springs, the E46 has linear front springs & progressive rear springs. The rate of the springs are indicated by color-coded stripes; I believe most ZHPs (& ZSPs) have three green stripes on the rear springs.Quote:
Originally Posted by pyrocrickett
And here's a response about spring rates specifically:
And finally, here's the latest (as of Nov 06) spreadsheet of color codes & options complied by E46F's JPR: Spring Data 253.pdfQuote:
Originally Posted by TxZHP04
Thanks for all that info. Unfortunately, it says I can't access the Spring Rate Data PDF.