Springs.

twinturbo · #1 26th October 2010, 08:26 PM

What springs are folk running?

And would anybody be able to recomend what I should realy be looking at for my car with the 2.9V6 which is probably 30% heavier than a Pinto/Zetec .

Cheers

TT

mr henderson · #2 26th October 2010, 08:34 PM

What I would do is make up some lengths of tube the correct length to act as dummy shocks, drilled so the ride height is what you want.

Then build the whole car up. When everything is installed weigh each corner, so you know what weight each spring is going to have to support. When you've got those weights you will need to subtract the weight of the wheel, tyre, brakes etc (all the unsprung weight).

I'll post how to calculate the actual spring required later.

Remember springs have TWO parameters, poundage and unfitted length. You need to know both to get the right springs

Bet you will get some replies that will give you a poundage to try, but not the length

Twin · #3 26th October 2010, 09:05 PM

TT,

I'd try 18 inch coilovers, but i'm not sure what poundage you'll need

THIS POST IS A PISS TAKE! DO NOT BUY 18 INCH COILOVERS.

Big Vern · #4 26th October 2010, 09:13 PM

Hi TT.
The length you need depends on the open/closed length of the dampers your using. So if you're using 'book length' dampers then you need 'book length' springs or you'll get into trouble with wrong bump and rebound lengths. Ash G. or any of the other who have 'finished' can advise on dampers used as can Saturn.
As for the spring rates you need to do as Mr H. says and find the corner weights first. It would be useful to measure the unsprung weights before your final assembly.
There are several 'programs' on t'internet you can feed this info into to calculate required spring rates. ( I use an 'industry' program but it's not user friendly so I don't offer it out as many proffesionals get tied in knots using it!)

Twin - on what basis would you try to fit 18" coil overs on a car originally designed for 14" open length? Spring lengths are likely to be 8" to 11" at most.....

Regards BV.

Twin · #5 26th October 2010, 09:19 PM

BV

Read the last line of Mr H's post

Big Vern · #6 26th October 2010, 09:37 PM

The read my post!
There are two lengths that could be used for the book. 13" open length and 14" open length
18" open length will not fit the book chassis without major rework. As TT has built his chassis I'm guessing he won't to chop it about
Further 18"open will give something like 6"+ of travel and with only around 4" ground clearance there would be all sorts of issues.

If you have something to offer please make sure it's based either on knowledge or experience rather than a random guess.....
Please remember there are people who could go off and do something based on your random remark wasting their time and money!

BV.