I got my sedan running a few weeks back and it does not handle very good, I think the rear springs are to soft. They are Pro coil overs and Im not sure of the spring rating that was on them but I took them off tonight and replaced them with 250's They seem to be the same as the first set. It is a 31 ford Tudor sedan, full fendered with a 32 tank in the back,sbc What do you think I should order for a stiffer spring? The shocks are about 10 Degrees Would 350 be to stiff?
i have 220 lb on my`28 tudor and they are at 27 degrees...which decrease the effective rate. i know you have some extra weight back there with the fuel tank , but 350 sounds very high
You need to weigh your car and do the math. Guessing will be expensive and painful. If you don't know how to calculate it, try a search for coil-over or shoot me a PM.
I would start by finding a place to weigh your car, front and rear. Also, it's more important to do the math correctly. You can measure how far your coils are compressing, and working backwards determine the weight of the rear of your car. Since you already know you just put 250's on, you'll be able to tell if they're too strong , or too weak. Just don't forget to adjust your figures for the 10 degrees from vertical. If you don't run the figures correctly, you'll be wasting money buying the wrong coil springs again. Good luck.............Woody
Mel I forgot to ask you earlier how far inboard from the backing plate are the lower mounts located ?
What else should I be looking at? Frame is a Roadster shop ch***is new Tri-4 bar with pro coil overs. Rear susp Traveled free with no binding before shocks was installed, Lower shock mounts are directly under frame rail. Front susp is a old dropped axle with a mono spring new hairpins and tube shocks. When driving it and hitting a pot hole or a bump of some sort it feels like the rear end is loose and has some body roll. when stepping on the running board it really leans over more than I think it should. I have been over every thing and can not find anything loose.
maybe you need sway bars to lessen the body roll. I have 180's in my highboy coupe. 350 sounds way too stiff. get it weighed before buying anything else.
Take it to a grain elevator and see if they can weigh the car for you. A friend just went thru this but had his car weighed at the Nationals in L'ville. 33 Ford with a BBC. Full fendered gl*** car. Front end was 1400 and the rear end was 1375. The springs that were in the car were 220 and bottomed out like crazy. If you're not careful, you'll damage the shocks like he did...one is leaking oil now. Pete and Jakes was a big help. With the weight, and the angle of the coilovers, they suggested 300lb springs which worked out great. Rides like a dream and you don't cringe looking for the next bump in the road. You would think a stiffer spring would make the car ride rougher... not true when they are selected properly.
250sounds about right to me . Check this link for a really good explanation on how to confirm spring choice by confirming design ride height of the shock. http://www.welderseries.com/blog/2009/09/24/rpu-coilover-mounting-tech-question/
put 300's on it and it seemed to take care of the problem it is a little stiffer but it dont through me in the ditch!!
Im running 250lbs on my 5 window coupe . Should be at 2500lbs when its finished. Thats what was recommended to me by TCI..
Not a huge fan of Pro shocks, but I don't think this is your problem. I would highly suspect the geometry of your four link. Can you take some picture of it? Reason I ask, I have had to fix a few triangulated four bar systems from ch***is manufacturers before where they had the upper bars mounted incorrectly. The worst one was an Outlaw 33-34 that did a sever roll oversteer. Spooky car to drive!
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