I have a pair of TCI Aldan All-American coilovers on the back of my Model A sedan. They ride fine (not too bouncy) except when encountering really big bumps................then the axle hits the frame (no snubbers) because there's only 3" of clearance between frame and axle. I thought the easy way out might be to put slightly heavier coils on, but I don't know what weight the progressive coils I've got now are so I don't know what to order. It's my understanding that progressive coils can't be measured accurately for poundage so I haven't gone that route. I don't want to marry a bunch of coil springs using trial and error, so my questions are; Is 3" inches of upward travel realistic? Is there somewhere besides TCI that can tell me what poundage my coils are? Does anybody know where I can get a few different set of coils to try? Is some HAMBER running a Coil Spring Exchange? Specs Sprung Weight.........................1000 lbs Shock Angle.............................20 degrees Shock Length...........................10.25" collapsed / 14.5" extended Ride Height..............................13.25" Usable Shock Travel..................4" (3" compression/1" extension) Coil Spring Size........................9-3/8" length / 117 lbs called for after doing the math Thanks Fellers
A progressive spring can still be load tested to see what the true rating is. The gap between rates is pretty high, base rate is probably 200 or 250 but the higher rate is over 400. My experience with them is it feels like you are bottoming out when it gets into the higher spring rate. Give George a call @ TCI, he is their lead Engineer and has been helping out on the phones the past few months. That is your best bet for an "exchange". -J
there should be a paint daub on the end of the spring. Sometimes you can see it other time you have to pull it apart. I f you can give me that I can tell you what it is. Are they Aldan's or All Americans because they use different color codes? 2 1/2" really isn't enough travel in the compression direction, we use 3" as a minimum. Progressive springs kind of suck and FWIW we just pulled 250# out of a 31 Victoria and put in 325#...much better.
The coilovers look exactly like the picture below, although I have never seen the box they came in. I'll look for the paint daub and get back. One other thing............for esthetics my coils are upside down compared to the ones in the picture, as I didn't think it mattered. .
After sleeping on it last night I realize that a stiffer coil will raise the ride height. I was initially hoping to run a stiffer progressive coil that wouldn't alter the ride height and keep the axle housing from hitting the frame. As dontlifttoshift said; 2-1/2" isn't enough travel, so maybe my plan is still OK as a heavier coil will raise the car 1/2" to give me the 3" I need. I may try to get rid of the progressives at the suggestions of slow4dr and dontlifttoshift. Need to look for that paint daub.
I found a BROWN and White marking on the end of one. I did a search on here and found the All-American chart which indicates my springs to be 300 - 480 lbs. After doing the calculations I came up with 117 lbs which seems awfully light, especially since the axle's hitting the frame now (or feels like it) with 300 - 480 lb coils.
What's your measurments eye to eye on the coil over with the car at ride height? If the shock bottoms out it will feel like it hit the frame. I try to set it up so the axle hits the frame right before the shock bottoms out....that keeps from bending the bolts (assuming you are mounted in single shear with a 5/8" bolt). Also do you know what the spring height is, installed and at ride height? that will help us guess how much weight is on the back end. You won't like what happens when you put 117# springs on there. That brown/white 300#-480# is listed as an 11" spring FWIW.
Ride height eye-to-eye........13.5" 5/8" bolt, single shear Spring height at ride height........9-3/8" Gross back end weight............1300 lbs Sprung weight of back end.......1000 lbs Unsprung weight....................300 lbs Front end weight...................1460 lbs
Are you sure the coil over isn't topping out? There will be marks on the axle or frame if you were bottoming out. With only a 1/2" of rebound that it is very possible that you are topping out the coil over. You might be a tad stiff with your spring. Try to buy good quality springs from someone like eibach, hyperco (best), or QA1, they are powdercoated dark red, blue, or silver in color (in order). I would try a 300# and see what happens. I assume you are in the lowest bottom mount right now, 300# spring and move up one hole on the lower mount and shoot for 13" to 13.5" at ride height and is there any way you can get more room between the axle and frame.
Please see my specs above again as I just edited the eye-to-eye and compressed coil lengths. I was originally in the lowest bottom mount, and yesterday I moved up one hole to provide 1" more clearance between the axle and frame. I haven't had a chance to test drive it yet, but maybe later today when I'm off work. Thank you for your help.
Finally found time for a drive. The ride seemed a lot better but still not optimum. The ride height seems OK so I may get shocks with a 1" longer stroke to alleviate possible 'topping out.' I'm gonna take your 300lb coil suggestion, and that with the extra 1" of clearance gained from moving the lower mount hopefully will do the trick. It may take a couple of weeks but I'll holler. Thanks again.
If your ride height is 13.5" then you should be fine. Let me know how the new springs work out. Donny