# suspension questions **URL:** \ **Category:** NYSpeed Automotive\ **Created:** [September 27, 2006, 11:42am UTC](https://forums.speedlife.net/t/suspension-questions/18112 "2006-09-27T11:42:22Z")\ **Posts on this page:** 16\ **Page:** 3
**Author:** ![Rx3](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/rx3/32/7194_2.png) [@Rx3](https://forums.speedlife.net/u/Rx3)\ **Post date:** [September 29, 2006, 4:12pm UTC](https://forums.speedlife.net/t/suspension-questions/18112/41 "2006-09-29T16:12:34Z")
:word: Good stuff right there. Although if he is gonna get that precise to where he’s accounting for oversteer understeer based on valving, your run of the mill D2 coilover isn’t going to cut it. You’re talking big $$$$$$$ or a lot of time tearing down a pre-bought set, learning how to rebuild them, and doing the shock valving yourself. D2 and other companies may work with you on spring rates, but I’m not sure as to the extent of support on re-valving beyond their spec range for the product. ---
**Author:** ![focusinprogress](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/focusinprogress/32/7227_2.png) [@focusinprogress](https://forums.speedlife.net/u/focusinprogress)\ **Post date:** [September 29, 2006, 4:29pm UTC](https://forums.speedlife.net/t/suspension-questions/18112/42 "2006-09-29T16:29:25Z")
well, i guess its time to let the sneakiness out of the bag. if i keep the spring in the stock location, its going to be in the way of a half-shaft. i will leave it at that. ---
**Author:** ![RobY](https://avatars.discourse-cdn.com/v4/letter/r/f1d935/32.png) [@RobY](https://forums.speedlife.net/u/RobY)\ **Post date:** [September 29, 2006, 4:53pm UTC](https://forums.speedlife.net/t/suspension-questions/18112/43 "2006-09-29T16:53:42Z")
^Woah I underestimate your sneakyness. This will be a whole other ballgame. What kind of rear suspension does the foci have right now? To get a rough estimate of wheel rates for one wheel: 1. Disconnect your sway bar. 2. Jack your car up. 3. Let the suspension go into full droop. 4. Measure the distance between your tire and fender. 5. Measure the distance between the spring seats. 6. Measure the distance between the shock mounting points. 7. Write all these measurements down. 8. Lower the car 9. Repeat steps 4-7 10. Calculate the diffrence in fender heights jacked vs lowered. 11. Calculate the diffrence in spring perches jacked vs lowered. 12. Calculate the diffrence in shock mount points jacked vs lowered. 13. Motion ratio for the spring is step 10 divided by step 11 14. Motion ratio for the shock is step 10 divided by step 12 Calculating these will give us a general idea of where to even start. It will help you choose SAFE springrates and non-pogo stick shocks for your ride. But it will be FAR from being a tuned suspension. ---
**Author:** ![Rx3](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/rx3/32/7194_2.png) [@Rx3](https://forums.speedlife.net/u/Rx3)\ **Post date:** [September 29, 2006, 5:03pm UTC](https://forums.speedlife.net/t/suspension-questions/18112/44 "2006-09-29T17:03:39Z")
Damn this thread is getting good. Gonna move it to Technical. We might have something to archive if this keeps up. Lots of useful info in here :tup: ---
**Author:** ![fairgentleman\_Z](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/fairgentleman_z/32/7263_2.png) [@fairgentleman\_Z](https://forums.speedlife.net/u/fairgentleman_Z)\ **Post date:** [September 29, 2006, 5:33pm UTC](https://forums.speedlife.net/t/suspension-questions/18112/45 "2006-09-29T17:33:23Z")
> [@Rx3](#): > > Damn this thread is getting good. Gonna move it to Technical. We might have something to archive if this keeps up. Lots of useful info in here :tup: I would disagree. The wheel rate formula as outlined in Carroll Smith’s _Tune To Win_ pg. 65-66 > Wheel Rate = Spring Rate/(Motion Ratio^2) We got half way there (well, except for accounting for tire deflections once the car is lowered, in such case it is always better to eliminate the variable and measure from hub center)… I could go on, but the more I think about it the more my head will hurt. My biggest suggestion is slap on some springs and dampers and tell yourself that the ride has improved. If that isn’t good enough for you then copy and paste other **sucessful** Focii owner’s set-up. Now if you want to go into technical, start out in layman’s terms and stick with the 5 Carroll Smith books. After that I can give you 200+ lines of MATLAB code that describes the behavior of a tire :bloated: The more I learn about it the more I realize that I don’t know. ---
**Author:** ![RobY](https://avatars.discourse-cdn.com/v4/letter/r/f1d935/32.png) [@RobY](https://forums.speedlife.net/u/RobY)\ **Post date:** [September 29, 2006, 5:47pm UTC](https://forums.speedlife.net/t/suspension-questions/18112/46 "2006-09-29T17:47:12Z")
You are right. Im trying to figure out where the squared comes from though. Its from the fact that the spring moves less distance per given wheel travel. I neglected that part. The ratio needs to be squared because of the diffrences in deflection distances wheel vs spring. Moving the spring half the distance creates half the force. this must also be factored into the lever ratio, which is why it is squared. Good source. Ill look into those books. ---
**Author:** ![MaximaSE98](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/maximase98/32/7600_2.png) [@MaximaSE98](https://forums.speedlife.net/u/MaximaSE98)\ **Post date:** [September 29, 2006, 5:49pm UTC](https://forums.speedlife.net/t/suspension-questions/18112/47 "2006-09-29T17:49:19Z")
so what ur saying is the costworth drive train will get in the way …so u need a whole cosworth rear suspension ---
**Author:** ![RobY](https://avatars.discourse-cdn.com/v4/letter/r/f1d935/32.png) [@RobY](https://forums.speedlife.net/u/RobY)\ **Post date:** [September 29, 2006, 5:50pm UTC](https://forums.speedlife.net/t/suspension-questions/18112/48 "2006-09-29T17:50:15Z")
> [@MaximaSE98](#): > > so what ur saying is the costworth drive train will get in the way …so u need a whole cosworth rear suspension That would be way to fucking easy… ---
**Author:** ![MaximaSE98](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/maximase98/32/7600_2.png) [@MaximaSE98](https://forums.speedlife.net/u/MaximaSE98)\ **Post date:** [September 29, 2006, 5:53pm UTC](https://forums.speedlife.net/t/suspension-questions/18112/49 "2006-09-29T17:53:54Z")
its eiterh that or plain RWD…which in that case Miata rear suspension…is the focus a double wishbone set up…i have no idea…i got crappy multi link beam ---
**Author:** ![RobY](https://avatars.discourse-cdn.com/v4/letter/r/f1d935/32.png) [@RobY](https://forums.speedlife.net/u/RobY)\ **Post date:** [September 30, 2006, 5:17am UTC](https://forums.speedlife.net/t/suspension-questions/18112/50 "2006-09-30T05:17:07Z")
Don’t doubt the multilink beam. It has better camber control than a strut. ---
**Author:** ![focusinprogress](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/focusinprogress/32/7227_2.png) [@focusinprogress](https://forums.speedlife.net/u/focusinprogress)\ **Post date:** [September 30, 2006, 2:24pm UTC](https://forums.speedlife.net/t/suspension-questions/18112/51 "2006-09-30T14:24:03Z")
well guys, im NOT using escort cosworth rear suspension. im using jag x-type parts. the focus has a double wishbone in the rear. so i either have to adapt it by losing the spring, or completely design a new suspension system from scratch. i figured a properly tuned coil over setup would be easiest. the jag x-type uses the same tranny as the focus, in an AWD format with a PTO mounted to the passenger side input shaft to connect a driveshaft to the rear:eekdance: ---
**Author:** ![MaximaSE98](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/maximase98/32/7600_2.png) [@MaximaSE98](https://forums.speedlife.net/u/MaximaSE98)\ **Post date:** [September 30, 2006, 3:47pm UTC](https://forums.speedlife.net/t/suspension-questions/18112/52 "2006-09-30T15:47:34Z")
No Cosworth, No Care…sounds like a hefty project ---
**Author:** ![focusinprogress](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/focusinprogress/32/7227_2.png) [@focusinprogress](https://forums.speedlife.net/u/focusinprogress)\ **Post date:** [September 30, 2006, 9:19pm UTC](https://forums.speedlife.net/t/suspension-questions/18112/53 "2006-09-30T21:19:49Z")
^ it is, the jag rear IRS is wider AND longer than the focus…so im gonna make a jig of the focus rear double wishbone and use the same mounting points somehow to get a jag rear diff and driveshafts in there. ---
**Author:** ![MaximaSE98](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/maximase98/32/7600_2.png) [@MaximaSE98](https://forums.speedlife.net/u/MaximaSE98)\ **Post date:** [September 30, 2006, 9:33pm UTC](https://forums.speedlife.net/t/suspension-questions/18112/54 "2006-09-30T21:33:12Z")
how much wider ---
**Author:** ![focusinprogress](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/focusinprogress/32/7227_2.png) [@focusinprogress](https://forums.speedlife.net/u/focusinprogress)\ **Post date:** [October 1, 2006, 8:13am UTC](https://forums.speedlife.net/t/suspension-questions/18112/55 "2006-10-01T08:13:45Z")
like a foot lol, im not sure, i havent measured it myself yet because i dont have one in my posession at this time, but someone else had access to one and told me it would need to be shortened in width and length ---
**Author:** ![focusinprogress](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/focusinprogress/32/7227_2.png) [@focusinprogress](https://forums.speedlife.net/u/focusinprogress)\ **Post date:** [October 11, 2006, 1:03pm UTC](https://forums.speedlife.net/t/suspension-questions/18112/56 "2006-10-11T13:03:51Z")
ok, so i have a new thought. the bottom control arm for the rear is a formed steel arm thats all solid, with a cup mount for the spring. what if i made something like a set of forks so that the driveshaft would fit between them but retain stock suspension geometry and bolt locations. [Previous page](https://forums.speedlife.net/t/suspension-questions/18112.md?page=2)