Jump to content

How much to cut off stock 510 rear springs


Recommended Posts

I’ve done a few searches but couldn’t find what I’m looking for. I’d like to know how much to cut off of stock springs to lower the rear of a 510 about 2 inches. Even if you didn’t go exactly 2”, throw out how much cut and the amount of drop you got.


  • Like 1
Link to comment
  • Replies 12
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

The rule of thumb is basically for every one inch of height of spring you cut, you lose approximately three inches in total height.


There are lots of variables here including, but not limited to spring rates (in lbs), sag i.e. how much they have been thrashed, the rubber that sits in the spring locating point (hopefully you know what im talking about here), shock absorber condition/travel, rolling stock (wheel OD), etc.


RW's advice having done this for over thirty years is "less is best".


It's a pain in the arse having to pull springs in and out of the rear end, however, better to do it incrementally than to hack heaps out of the spring and fuck it up.


Dont forget to shake the bejeebus out of the back of the car (I find it best if you can stand in the trunk and jump up and down), to settle the springs when they are back in.

  • Like 2
Link to comment

Increased spring rate in the rear may induce oversteer, however, this can be countered by a number of variables i.e. different tyre pressures, toe in/out, caster adjustment, larger diameter front sway bar etc.


If you are using standard springs, the difference in the spring rate should be negligible.

  • Like 1
Link to comment

When I did my D50 springs, I think I ended up with 1.5 coils. 


I cut a little at a time, reinstalled. Jounce the rear, roll it back and forth, check. Pull it out again, cut about another quarter coil,  and repeat. Then account for a little more drop (not much) after it settles.

  • Like 1
Link to comment

I don't know what the ride height is using the D50 coils as they are at full length, but the rate works out to 497.6 lb/in. or about 130 at the axle. Again, I don't know what the stock 510 rear spring rate is (to compare) but the fronts are 89 lb/in so the rears somewhere around 380 or 100 lb/in. at the axle.  The Dime quarterly article says cutting one coil off brings it to 5.5 coils and 155 lb/in at the axle. Cutting to 5 coils remaining is 170 lb/in at the axle. 5.5 coils will give a ride height of 6.75" from the ground up to the under side of the rocker just forward of the rear wheels. 


150 is a nice conservative amount that I run on my 710 fronts. Can't imaging twice this being run on some 510 for racing... w/e

  • Like 1
Link to comment

Cut half as much off as you think.  That's what I've learned haha.


This is what I did. I cut 1/2 a coil, it’s still a tad high and the rear is softer than the front still. I’m going to take another 1/2 out when I get around to it. It drives much better now.

  • Like 1
Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...

Important Information

By using this site, you agree to our Terms of Use.