[TheCiscoKid]

I have a 38 Chev 2 dr, used TCI ifs, CE rear leaf. I found the car rode like a tank. I want a softer ride.The car has 1500 miles now, so springs should be broken in. It had cut coil springs originally and I swapped them for TCI 350lb.These are their lowest rate springs. They will not settle enough so the lower A arm are horizontal, free height 13.5'', installed 11''. I was looking at spring recommendations and Eaton only has one spring that rides at 9'' which is the height I need, a 325lb. The easiest spring for me to get is a CE spring. I installed their 325lb spring , free height 12'', installed 9'' and the A arms sit horizontal. The ride is less harsh but the car body tends to ride with a bump. I took car out with worn out shocks,then installed a new set of KYB GR2 shocks and really couldn't feel any difference. The road I'm driving is wavy and full of cracks and some holes,maybe not ideal, but typical. I'm thinking of trying 300 lbs springs,but my understanding is that front springs should be firmer than the rear springs( which I can't rate).
My rear suspension still bucks on bumps,I tried a ride with no shocks. I'll take out the smallest leaf and see what difference that makes,but don't want the rear to sit lower.My rear springs have settled so they are flat/ no arch.
My question is how smooth can you or do you try to get your ride quality and how do you judge the ride??

 

[cboy]

I know it won't be of much help but just wanted to say that you are not alone on the issue of getting a good ride out of your springs. I find it one of the most complex and challenging parts of building any hot rod, from simply installing a larger engine all the way to a total scratch built car. It is a tricky business to get the ride characteristics you want while maintaining the ride height and stance that you want. Change one, and in most cases you change the other. Even when using adjustable coil overs. You can try to compensate by using spacers and other tricks, but it seems to always be a bit of a crap-shoot to get it right.

The best solution I ever saw was a little yellow roadster pickup out of southern Illinois that was built with fully adjustable top mounts on the springs and shocks. By altering the location of the top mounts and using different height springs, he was able to dial the truck in to exactly the ride he wanted. A real piece of engineering.

But that solution is far from reality for most of us. So we just have to struggle with a lot of spring swaps...pretty much as you have been doing.

 

[TheCiscoKid]

I imagine alot of guys buy suspension kits and just put up with the ride quality. I expected the kits to be designed for my cars ride, but now realize each car to be too different.The Rod shop where I bought the springs says a majority of their calls are about ride quality.
How or what would you call a good ride quality.??
My car was almost "need a kidney belt ". The front suspension now isn't as harsh, doesn't bang, but the car body follows a bump. I don't know if a softer spring (and how much so) will give more and allow the car body to remain flat or just leave this as I don't know if its possible to get a Caddilac ride.I could go softer and have the car doing nose dives when stopping.

 

[enjenjo]

I have never been pleased with CE rear springs. they are way too stiff for most cars. For this reason, I switched to Posie's rear springs for my last several builds, and they ride much better.

But since you have CE springs, that is not much help. I think removing a leaf or two might help, but it may change ride height too much.

 

[JohnTN]

Isn't one of the limiting factors the spring height that can be accommodated in a street rod? Most modern cars can have springs much longer than 12 inches in the rear, whereas most street rods must use 12 inches or shorter. This means the springs and shocks have to be stiffer that what will give a Cadillac ride.

 

[cboy]

Isn't one of the limiting factors the spring height that can be accommodated in a street rod?

To some extent, yes. But height is only one of many factors that determines a spring's effectiveness. The "springiness" of a spring is also determined by the diameter of the spring material, the type of steel used in the spring, and the overall diameter of the coil. So while spring height makes a difference, you can compensate for any lack of available height by altering any or all of the other factors involved in making a coil spring.

 

[TheCiscoKid]

I think number of coils count somewhat, especially if you cut them. My original cut springs were 12'' and 5 1/2 coils, TCI 350lb were 13 1/2'' and 6 1/2 coils, and the CE 325lb are 12'' and 7 1/2 coil. I had to take the spring compressor apart inside the coil spring to get it out because of the smaller spacing in the CE spring. I'd like to try a 300 or 275lb spring but it's a pain doing it and I've painted my springs ,so I can't exchange mine.

 

[454 Rattler]

I really thought you would get more feedback than this.

I've only met one person happy with the ride of his street rod. That was the guy that cboy was talking about with the adjustable suspension.

I've got a 36 Ford 2 door with a 350/350 combo and Mustang II front-end. It's got 11"tall springs and stock spindles. It DOES NOT ride like a Caddy.

I know from experience that coil-overs (on my 29 Coupe ) are not too soft. My friend, Bill tells me that his Bagged pick-up doesn't ride great either.

So what's the answer ? Is anyone happy with the ride of their car ? If so, what combination do you have ??

Bill says "It's a street rod not a Caddy. Live with it !" Maybe he's right.

What do you think, guys ??

454 RATTLER

 

[cranky1]

Years ago I read an engineering article about springs (WAY over my head lol). It talked about everything about the vehicle including how much power it had, wheel base, weight (front vs rear too), size of wheels and tires, unprung weight, the whole nine yards. A lot of consideration goes into suspension design and spring selection. Not sure how much spring you should have in the rear for street aps but my last race car had 110 lb coil overs in it on the rear with 6 cylinder torsion bars up front. Most race suppliers always say you need more than what you really need and that may be true in your case too. Generally, if your rod rides like a truck, you have too much spring in it and you may need to go to a spring shop for custom made springs if you can't find something off the shelf that will work.....

 

[Bryan59EC]

I think number of coils count somewhat, especially if you cut them.

Yep---this is true

A coil spring is nothing more than a torsion bar wound up into a coil.

For instance

A coil that is 12" wound with .625 diameter and 12 coils, will be much softer
than the same spring with 8 coils-----this is because the "torsion bar" is much shorter. (for any given height of the spring)

I'm no expert on this, but my common sense tells me that a spring with more coils would be softer than than one with less.

 

[cranky1]

Yep---this is true

A coil spring is nothing more than a torsion bar wound up into a coil.

For instance

A coil that is 12" wound with .625 diameter and 12 coils, will be much softer
than the same spring with 8 coils-----this is because the "torsion bar" is much shorter. (for any given height of the spring)

I'm no expert on this, but my common sense tells me that a spring with more coils would be softer than than one with less.

Yes, you are right about that....

 

[bobinbc]

If you can get your hands on a Moog spring catalog you might find it helpful. Used to have one but I loaned it out and it never came back, hate it when that happens...

 

[TheCiscoKid]

I've read quite a bit, found articles that are over my head, things like spring rebound rates. I haven't found enough info on weighing my car to figure out spring rates and how would this apply to my leaf springs anyway?.
When I bought these suspension kits I thought they would be engineered for my car. I even bought the sway bars. I've read that every car is different and kits can't account for these variables. I have A/C, run bumpers and I now have a softer coil springs on the front than TCI sells and they're too firm, so I'm calling "BULL ****" to the designs. My CE leafs have settled to be flat and that has the harder to flex. They'r a super stock type, don't know if that matters.
As for these being street rods, not caddys, there is no reason a car shouldn't ride well. For me if it doesn't ride well, then it doesn't handle well and is unsafe. I don't know what your roads are like, but I see craters here that looks like the road to Beriut.
How do Posie springs ride? Anyone have a good ride,tell us?Street rod on an Accord chassis? )

 

[aosborn]

There is no reason that you should not be able to get an excellent ride out of your 38. You are correct that the ride rate should be different (and likely will be) front to rear and typically the front ride rate is stiffer. I would go ahead and install lower rate front springs to achieve the ride you are after. Usually a 50lb change in rate is reasonable so as to avoid buying more springs than you need. It is better in my opinion to go on the soft side with coil-over springs and pre-load them more to get to your ride height back.

As for the rear, while leaf springs are designed to work as a unit with all the leafs in place, I have had much success in removing leafs to lower the rate. I would recommend removing the third longest leaf keeping the second longest leaf in place to support the main leaf and maybe remove one of the shorter leafs and give that a try. If the car then sits too low in the rear, adjust it with shorter lowering blocks if you are running them, or change your shackle length to compensate.

With softer springs, you may need to increase the stiffness of the anti-roll bar(s) to control body roll. Be aware also that with decreased spring rates, the dampening rates will likely need to be decreased also with softer shocks. Another major factor in realizing a good ride on hot rods is unsprung weight. Heavy wheel and tire assemblys (wire wheels are the worst) on a light car are hard to control with shocks and springs and still allow a decent ride.

Andy

 

[TheCiscoKid]

Thanks Aosborn.You made some good points. I'm not using lowering blocks and never thought to length the shackles. I'll try taking out the third leaf.
I'm not using coil over either but that me realize that a lighter coil spring will allow the A-arms to settle more. I put 200 miles on and mine are just above being horizontal now. So a lighter spring may need shimming.
How do I find lighter shocks, they seem to be listed by lengths. For Mustang 2,Napa showed only a regular shock and a gas shock that was more than twice the money, KYB Gr2 literature said they ride better than original, but I didn't notice any difference against the worn out shocks.

 

[cboy]

... How do I find lighter shocks, they seem to be listed by lengths.

One option is to invest in a set of Carrera A1 adjustable shocks. I put a pair on my '32 pickup and saw a noticeable difference. You can dial them in to fine tune your ride quality. I used them because my Pete & Jake's shorty shocks just wouldn't hold the tires to the road and I badly scuffed a set of tires at just 12K miles. Since switching to the A1 shocks, my tire wear has been vastly improved and the car ride smoother. These shocks are pricey, but in my experience, worth it.

 

[bentwings]

I can say a few words about the QA-1's. They were my dream shocks for when I became weathy. Fortunately ??? Summit has (d) them on sale recently so I broke down and got the QA-1 Must 2 front single adjustable coil overs with the softest spring...375. Now, my Willys only weighs 2600 pounds with 1400 on the front so I thought it would be a much better ride than the goofy stock springs. Well it is better but certainly know Caddy ride. They even recommended the 500 springs which would not have compressed much at all. I have parallel to slightly up at the outer a-arm setting for ride height. I also thought a sway bar would be in order.

Well scratch the sway bar. The only one available and common to all mfg is about 1 inch dia and so stiff that there is almost no give side to side. Great for road racing but way way too stiff for a light car. I have very light rear springs 165 I think. With the narrowed prostreet rear end I have to run about 1 inch pre load or wedge in both the left front and right rear to have any control of the right rear tire. This seems to be about the max adjustment as any more affects turning too much.

I run on #6 on the adjustment screw to get rid of the pitching and bouncing in the front end. So far the ride is much better but still not what I expected or wanted.

The Must and Pinto were both much heavier cars than my Willys but I sure don't remember them as being rock hard riders.

I agree that there needs to be better springs/shocks for our lighter cars.

 

[aosborn]

How do I find lighter shocks, they seem to be listed by lengths. For Mustang 2,Napa showed only a regular shock and a gas shock that was more than twice the money, KYB Gr2 literature said they ride better than original, but I didn't notice any difference against the worn out shocks.

QA1 adjustable shocks are a great choice, as are other single and double adjustable shocks. To find the right shock at a parts store can be a crap-shoot. Usually the lower cost the shock the softer they are. High pressure gas shocks (the ones that expand on their own when compressed like the KYB Gas-a just) are usually stiffer than low pressure gas (KYB Gr2) or plain oil shocks for the same application. I am also curious as to how you determined the old shocks were "worn out"?

Another point regarding spring selection. To help determine what springs you need for the front end, you need to do a little math. If you know the rate of the springs currently in the car it makes it pretty easy. Measure the height of the spring at ride height (installed height), then remove the spring and measure the height while it is sitting on the garage floor (free height). With these two dimensions you can determine how much weight the spring is supporting. Subtract the installed height from the free height and multiply by the spring rate. For example, if you had a 350lb rate spring and it is compressed 2" when installed it is supporting 700lbs. If you want to install a lighter rate spring and keep the same ride height, you would have to have for example, a 300lb spring with a free height that is about 3/8" longer so it is supporting the same 700lbs at the same installed height.

If you also want to lower the car and the rate, you just need to adjust your spring dimensions. For example, to lower the car about 1/2" and reduce the spring rate to 300lbs, install a 300lb spring that is only about 1/8" or so taller than the 350lb spring it replaces. Because the spring is mounted inboard of the tire/wheel, the effect of the reduction in height of the spring is multiplied by about a factor of two when adjusting ride height. Example, a 1/4 inch reduction of installed height of a front spring will lower the car about a 1/2".

If you can't find what you need off the shelf, contact Eaton Spring Co and tell them what spring you need. They will need to know the free height, installed height and the spring inside dimension you are after. DON'T BUY CHEAP SPRINGS! Good springs won't settle more than about 1/2" ever.

Andy

 

[TheCiscoKid]

I was just playing with the old shocks, one seemed easy to push in and pull out, the other shock was hard to push in and popped back out.No oil leaked out, guess the shock was just bad.
I used TCI and Chassis Engineering springs, don't know if they're cheap.The KYB GR2 shocks were double the price of a Munroe etc.
My A-arms sit just a bit above level, ride not too bad with 325lb coils.I think I'll take a leaf out of the back and see how it rides then.

 

[cboy]

Well it is better but certainly know Caddy ride.

I just wanted to follow up on bentwings' insightful observation here to make sure no one got the impression from my recommendation of the A1 shock that it would be some sort of cure-all for obtaining the perfect ride. Shocks are never going to overcome an inappropriate spring rating choice. On the other hand, you can have a nearly perfect spring rating choice and ruin it with a poorly matched shock. What the adjustable A1 shocks do, is simply allow you to fine tune the SHOCK portion the equation without having to totally replace the shocks each time you want to take a step or two towards "firmer" or "softer". But you have to get the SPRING portion of the equation dialed first...and that, in my estimation, is the more difficult task.