[Irelands child]

While the car is 'sleeping' this winter, I want to do a few needed changes. The suspension is coil over with the TCI All American set up, 10" height, about 2.5" ID springs and set at about a 15* angle. I am using what was supplied - 200 lb in the front and 250 in the rear. The car wallows with these springs.

A bit of history - about half way through my build, the dealer that sold the chassis to me called and said that the wrong fronts, 250#, were supplied by TCI and I needed to do an exchange to the 200# which I did. After I got the car together, it now looks like the 250's or better would have been correct anyhow as I had to raise the adjusters ~2" to get reasonable road clearance and to level the lower 'A' frames.

This is the set up currently with the adjusters "'up" poor quality photo - sorry)



I've done some on-line research and have become even more confused as different chassis manufacturers call for different rates. I've seen 175# to 400# for the front end of my 2500# roadster, which with the additional engine setback and '32 style gas tank is close to 50-50 distribution (yep, should know exactly, but wont happen for 3-4 months now).

There are other '28 - '32 roadster or coupe builders here with coil overs. My question is what rate springs did you use and did you consider progressive rate springs (mine are not currently)

Dave W

[MRTS33]

If the shocks are made by the same manufacture and same type front and rear then swap the springs front to rear. Are you bottoming out on the wopdedos ? I would think there is more weigh up front than rear. By the picture the front does look pretty close to perfect to me with the lower a-frame level. Just my .02.

[johnsongrass1]

What is it your wanting the car to do? Stiffer ride? Your worried about bottoming out?

If the adjustster postion bothers you then just get longer springs and move the adjuster down. If it's not bottoming out now, wether it be Coil Binding or the shocks, then I wouldn't worry about it,

[S10xGN]

My '72 Maverick with it's MII based R&C front clip has 450# coilovers and rides perfectly. This car is really light and has an all aluminum LS-1, prolly similar in weight to your car. The guys at R&C originally recommended 550# springs until I explained about the aluminum engine. I'd also be concerned about your rear springs, most light cars use 130# to 150# springs (unless yours are severely angled).

Russ

[1971BB427]

I'm really surprised that a spring this heavy would wallow, or be mushy on a car that light?? I'm running a 175 lb. spring on the back of my Austin gasser that's probably a bit heavier and it's stiff as heck. Wish I'd gone a bit softer, and might change them someday.

[Irelands child]

Guys - I'm getting all kinds of conflicting opinions and as you can guess, the confusion still remains. I looked on the HAMB tho didn't post and there are conflicting opinions there as well as far as springs. Yes, my car wallows, particularly in the front. With the adjusters up as high as they are, it does concern me that I will get into coil bind. But - the pundits never said it would be easy.

Thanks for taking the time to respond.

Dave W

[aosborn]

Wallows... does that mean it has a lot of body roll on corners? Or does it mean that the car bounces several times after hitting a bump going straight down the road? Does the nose dive when braking? A lot of squat in the rear when accelerating? If you could give us a few more details we could give you more help. If the car bounces after hitting a bump, you might just need stiffer shocks. If body roll is the problem, stiffer anti-roll bars is an option. I would rather have the car more softly sprung and have more anti-roll than having a car with too stiff of springs.

To check for coil bind, multiply the number of coils in the spring by the diameter of the wire and that will give you the stack height. With the coils removed and the spring adjuster nuts in the position where they are with the springs installed, reinstall the shocks and set the car down on the bump stops, then measure from the upper to lower spring seats. If the number is larger than the stack height, you won't have coil bind, if it is less, you could.

Andy

[S10xGN]

Find the phone numbers for some of the larger coil-over outfits, call them, and get their recommendations.

Russ

[Irelands child]

Originally Posted by S10xGN

Find the phone numbers for some of the larger coil-over outfits, call them, and get their recommendations.

Russ

That's exactly what I'm going to do IF (?) I can ever get TCI to confirm for sure EXACTLY what the spring 'as manufactured' dimensions are. TCI is not the most forth coming for information. If I continue with the roadblock, then I'll do the disassembly measurements, but don't want to do that first unless I have to. My first choice is AFCO

I'll eventually post how I end up!!!

Dave W

[1971BB427]

Most spring/shock suppliers have a chart to determine what spring will work best for your car, but they need several things to properly size the spring. Weight aat each axle, so you'll need to drive the car somehwere where it can be actually weighed at the axle.
Length of the front control arm and distance from pivot point to spindle, with shock location. (if it has independent suspension)
And finally the angle of the shock, which can drastically change the rate. The spring rate needs to go up as the shock lays over more. Straight up gives the highest spring rate.

[Irelands child]

I've been busy so haven't spent any time puttering with the car for the last few days but I did get an interesting catalog today, an AFCO

This cat gives base points for springs - and my car, 1200-1500 front end weight and at a 15 degree angle (it's actually 13*) calls for a 372 pound spring. The closest is 350. The rears and at the same angle, calls for a 140 pound spring .

Next step, a call to TCI as well as AFCO 'cause whatever I have - and if their numbers are correct, the springs are way off, both ends. I also want to try to find a set of scales to borrow for a weekend just to be sure of the weights.

Dave W

[matts37chev]

are they the same size front and rear, so you can switch them to see if it gets a little better?

[Irelands child]

Originally Posted by matts37chev

are they the same size front and rear, so you can switch them to see if it gets a little better?

Matt - I had considered that and they are the same physical size but that can end up a LOT of extra work laying on my ancient and achy back for an experiment on a full fendered Model A with a '32 gas tank. Especially in the winter when I can't do any test drives in the snowy/salted roads. After I talk to the vendors, I might end up putting the 200# fronts in the rear, but if AFCO is correct, the 250# pounders are......useless...... and will eventually end up under someone elses car.

Of course, it also ends up as an excuse to change the powder coated springs for AFCO's chrome to match everything else on the suspension
Dave W

[matts37chev]

Originally Posted by Irelands child

Matt - I had considered that and they are the same physical size but that can end up a LOT of extra work laying on my ancient and achy back for an experiment on a full fendered Model A with a '32 gas tank. Especially in the winter when I can't do any test drives in the snowy/salted roads. After I talk to the vendors, I might end up putting the 200# fronts in the rear, but if AFCO is correct, the 250# pounders are......useless...... and will eventually end up under someone elses car.

Of course, it also ends up as an excuse to change the powder coated springs for AFCO's chrome to match everything else on the suspension
Dave W

I can understand that

[johnsongrass1]

I advise you look into Balck Magic Springs. Their rates are far more consistent than AFCO.