Today while driving my old sedan to the shop I hit a pot hole and was actually shocked to hear a loud thud when the frame bottomed out on the axle,I pulled over thinking I had broken a shock or worse but everything looked OK. This has never happened in the past even with the grandkid's in the back seat,but it's been several years since anyone was in the back,only luggage rides there now. I built the car more than 20 years ago and the rear is suspended with coil-overs so I'm thinking the springs may be worn out. If I were to re-do the car I would go back with a transverse spring but that ain't in the cards,what's the thought to replacing the springs or is there a better coil over that has been made since the old TCI ones I used 2 decades ago? HRP
Unless you have a broken spring, or broken leaves in the spring, it is more likely that your shock has failed.
HRP, shock technology has gotten a LOT better in the last few years. Perhaps, if a shock has gone bad, some smart shopping with specifications of what you need is in order.
Over 20 years,that pot hole many have got a bit deeper LOL,or the load in the driver seat could be a tiny more from a longer belt or something.
Danny a pot hole in S.C?I thought we got them up here in the winter if we got a little snow.LOL.Bruce.
Dana,that's cold but your right I do weigh more now than I did 20 years ago but the left rear was what dropped off in the tank trap. HRP
I'd probably buy ones from Stock Car Products, Speedway or somebody like that that makes racing springs for coilover shocks. You can get them in about any rate you want them. I have a coil spring rate checker, if you want to bring one by and we can see what you have. You can go back with the same thing, or bring them up a bit. Good Luck.
When I bought my coupe in '97 it had Spax coil overs that were GONE!!! I replaced them with VIPER coil overs from PETE&JAKES . They are still goin good............
Id keep drivin the old heap with those shocks. If you bottom out a few times more then change them out. Maybe it was just a really big hole.
Maybe I do just joke around more then I should,but that's me. Springs do get lower with time for real,had to adjust hights in race cars often. Checks on spring rate change happen {get softer}in less time then many think an need replacing in race car. For the street just adjusting up for ride hight is often enough.
Have a buddy with an OT Pro street type 4 link set up. Cheaped out on the original build shocks and springs. Didn't last 3 years, went back with QA1s after talking to their great tech line and the car never rode or handled better. Not saying your originals were cheap 20 years is great miles to the dollar! Technology has improved almost everything HRP, tires, shocks, electronics, tools you name it. Take a close look and you'll be presently surprised. Except for the cost that is. Joe
No problem Dana,I know you were jerking my chain,my old shocks are like the early Jag type and are none adjustable. HRP
Short answer is there are better shocks now than there were 20 years ago, I'm sure you know that. But real question is, "do you know what caused the thud"? And if not, why think about upgrading the shocks?
The Moredoor runs QA1's on it. They also make different spring rates and stiffness levels. I'd give Speedway or Summit a call and talk to a tech.
About 10 years ago we installed the QA-1 shocks on a '53 Ford pick-up,I don't know the coil spring rate but I remember the shocks had a adjustable valve and at one point we set it and 3 of us stood on the frame and it barely moved we then positioned the valve as far as it would go in the opposite and one person standing on the frame could make the frame bottom out. I was amazed and yeah they are expensive. HRP
Been running these adjustable Aldan coil overs for nearly 18 years. Gave them the weight of the car, they selected the springs, and compression/rebound dampening, and they have worked perfectly. I did dial the valve up one click from the factory setting after a test ride. Great people to work with.
With my stock-ish '59 Ford suspension, I've whacked some pot holes that have rattled my fillings. Definitely hit the snubbers hard. Shocks are new, rear springs new, stock front springs less 1 coil. Avoid those big pot holes is my best advice.
They make an interior mounted switch now that controls the dual dampening on the shocks. I sent them my old shocks off the 442 and they retrofitted them with the air control switch so you can make adjustments form the drivers seat.
Pot holes are bad news. Here in Tucson we drive like a road course avoiding them. Cant tell if some fool is texting or missing the pit.
Springs do not "wear out". they have the same stiffness throughout their life. They either break which would be obvious, or over zillions of cycles they slowly lose their "set". If car is sitting lower, just pull them out and get them re-set .
That sounds good in theory, but in practice it just isn't true. Spring steel does get fatigued with age and use so even if you attempt to "reset " it, it will quickly return to the fatigued condition. The only way to restore it is to repeat the original heat treatment and at that point you might as well go with new spring steel.
It is good in theory AND in practice. The fatigue you are mentioning is the spring steel losing it's set. Cold setting is the best way to re-set the springs [blacksmiths called this "cold bulldozing"] What you're basically doing is "Controlled Bending" of the steel beyond the point of yield.iea I have pulled f***ed old springs out of a high mileage car where one side has completely sagged ,and measured the stiffness from L to R.[before resetting them] The results have always been consistent. Professional spring shops prefer to use heat resetting [which is at lower temps than most people think] because it is less time consuming and less skilled when doing volume. They can use an LPG oven
The Jalopy Journal
