Technical Fenderless Model A - Rear Coilovers - PLEASE HELP

That's a really dropped crossmember. As you already mentioned, flattening that out some would be another way to drop the ride height a little. Start with sorting out the spring, get the right length so that shackles are at the right angle, with reversed eyes, and a good spring shop can adjust the arc as well. If you can't get it dropped enough there you might have to flatten the crossmember. And those pics showing the ride height with the soda can really show how it does need to come down some, at least 1.5", maybe closer to 2 or 3 inches. Get that inner fender line right at the outer diameter of the tire and you got it right.

 

The measurement from hanger to hanger is approximately 46.5 or 47, I do think I'm gonna change to Radials, but I might wait for the new Cokers that claim the bias look but are radials, and the cheap classic VW shocks have been ordered, I do think that radials and soft shocks will make a big difference, I removed the shocks this morning and drove it and its definitely softer.

 

yeah the wheels are 3 inches from the fender line, wish it was more like 1 inch

 

Im no pro but that shackle angle is ALL wrong, they need to sit at 45 degrees.

Measure the distance between the spring hanger eyes. Deduct 3 inches. Try and find a reverse eye spring from Posies etc that is that length.

Leaving the spring that way and only adding a change in shocks is not the full answer here.

 

Just wanted to update you all... I did install the VW shocks, I did have to remove the sleves from the shocks because the sleeves were too small for the shock bolts I have on the car, its definitely softer but even though the website where I purchased them say oil filled I suspect they are gas filled buttt they are thinner and less stiff so I do feel a difference in suspension travel. I do agree that the shackels are not at the propper angle for model a's but it is at 90 degrees which still allow for travel, if fact most new trucks that have leafs on the rear have the shackles at 90 degrees. I did record a few clips to show the car bouncing with no shocks to show the leaf springing back , I will try to post the short clip later to show. FYI the shocks are for a 1962 VW Bettle, they are around 16in extended and 9in compressed, I just drilled out the sleeves.

 

Yes a newer truck shackle is 90d, but they only have a shackle on one end of the spring. But you say you have a pan hard bar on the rear, so it is controlling side to side movement. Your shackles are probably fine as is. How much travel do you have before the axle hits the frame? Do you have rubber snubbers? You might try removing the shortest leaf. And I agree, play with the air pressure.

 

Slack shackles necessitate a Panhard bar.

 

I have coil overs on my roadster, but the I had the chassis set up with a round tube crossmember to accommodate them vs. a leaf spring. My car is 'glass, but it's VERY heavy, I used the lightest springs on the (Speedway), it rides and handles great. If you decide to go with coil overs, you'll need a Panhard bar to keep the axle in place side to side. As pointed out, the shackle angle is ALL wrong, so that could be the issue. Although I see you said the spring still can flex and move the shackles, it isn't right. You should need a spreader to flatten the spring to get it in the shackles, and they should then be at an angle, not straight down. Maybe the spring needs to be re-arched?