Now that my car is pretty sorted out... I'm not into how high it is. I don't want to slam it. I still want to keep it street friendly. However it's just too high for my taste. How much should I lower it? I've been reading how to lower. I'm mechanically inclined and have a shop full of tools. However I don't know these systems. It's an IRS rear if that helps. Supposedly a 73 torsion front.
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Are the tires 165x15's? If so they are probably 80 series tires so high side walls. If you are in need of new tires (or they are more than 6 years old) consider going with lower profile tires. The 165/80's are becoming hard to get - despite the # of 70's cars that wore them back then. So down the road they will be more costly (and lack modern day handling).
Using the Miata tire size calculator https://www.miata.net/garage/tirecalc.html going to a 185/65x15 will lower the car 1/2" right off
Tire Size Comparison
Specification Sidewall Radius Diameter Circumference Revs/Mile Difference 165/80-15 5.2in 12.7in 25.4in 79.8in 794 0.0% 185/65-15 4.7in 12.2in 24.5in 76.9in 824 -3.6%
Looking at where the fender is in relation to the tire/rim, I would start by moving the spring plates 1 outer spline (should drop the rear 3/4- 1") and see what you think of it. You may find 2 outer is a lot, especially if there's a deep sump on the car. The inner spline count is different so you can mix and match to get exactly what you want. Make sure no body parts are under the spring plate when you pry it off the ledge, as it's preloaded and will break bones when it snaps down. I'll look later to see if I have the chart saved, or you can find it on the Samba or maybe the Sway-a-way site.
Offset front spindles will get you 2 1/2" lower right off the bat, and you can fine tune it with beam adjusters. If the beam doesn't have them already, it will have to come out to have them welded in. Don't forget caster shims under the bottom beam so it's safe to drive at highway speeds. Just be aware that the offset spindles will space the wheel/tire out and additional 1/2-5/8" on each side.
The whole thing is going to be kind of a hit and miss affair. Where you end up will ultimately depend on what you like, so be prepared to do some things (like the rear torsion adjustment) more than once. Al
PS- and don't forget before and after pics...
Edit- According to the chart, 1 outer spline lowers the rear approx. 2"
ignore the first bit- I put the wrong thing in and now I can't get rid of it.
Al wrote: According to the chart, 1 outer spline lowers the rear approx. 2"
That's true, and a single inner spline is about 2-3/16", BUT combinations of inner one way and outer the other way in one spline increments will get you about 1/4" of up or down, depending on which way you want to go.
This applies to either swing-arm or IRS rear ride height:
https://www.speedsterowners.com...rear-ride-height--vw
Just remember, if you go too low you'll bottom out either on the suspension snubber stops or by hitting the tires on the inside of the body.
The front end could be easier or harder than the rear. If it already has adjusters on the front beam you're golden - find out how to adjust them and just do it. If it doesn't have adjusters you can either add them as noted above or go to dropped spindles for about the same money.
Gordon thanks! I'll look at the sump too. That's priority. Not hitting that!
