I'm using the '47-55 front shock brackets on my '36. Can someone tell me what angle the factory put the shocks on those trucks? I was going to do about 30 degrees, but the lower bracket that bolts on the axle seems like it's somewhere around 40 degrees.
The front shocks on my 50 are sitting around 53plus degrees.
Craig
My '50 Chevy 3100 5 window, '62-235cu, 3:55 rear My truck ....... Respect The Rust If I'm not working on my truck, '65 m00stang or VW camper, I'm fishing with the wife or smoking Salmon.
RB, Were you measuring your angle from vertical or horizontal?
Most shock measurements are taken from vertical making cmayna's measurement 36/37 degrees from vertical so if that's where your taking your angle from, 40 is pretty close to 37. Is your engine and trans in the truck?
The greater the angle from vertical, the less effective they will be.
1950 Chevrolet 3100 (Ol' Roy)
1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)
Otto, I was measuring from vertical. Engine and trans are in, truck on the ground. It sits pretty close to level. Maybe a couple degrees of rake toward the front but not much.
Since I'm using shocks with studs on both ends, I wanted to make sure I'm getting it close to how the factory set them up. Seems like my thinking was pretty close.
My '37 has the shocks at 19 degrees forward from vertical. It had some 3/8" flat bar welded to the frame when I got the truck, the top has a 90* bend for the top shock mount, they are pretty close to straight up and down. I have to use a Pinto rear shock due to the length restriction so I have very few choices when looking for shocks. I added a piece to the top mount to let the shock lean forward to take some of the efficiency away.
I have leaf springs from Detroit Spring, they custom made them for the weight of the truck, I wanted a softer ride and wasn't worried about the load capacity. They work good and ride nice, but the truck still has that four leaf spring ride. The front still is a little stiff but much better then the solid ride it had with stock '37 springs. Leaning the shocks made a difference, and one of these days I am going to lean them some more.
I attached the shock efficiency chart so you can see what the angle does to shock performance. It's a little misunderstood, the shock it self doesn't change, what does change is how much it compresses and extends while driving. The more it lays over, the less it moves in and out, thus reducing it capacity to control bounce. It's a good way to fine tune ride quality.
FYI, the stock '50 and newer trucks have a spring rate that is half of what the '37s had, and the trucks are heavier, that's just shows how over sprung the early trucks were. Joe
Not that I didn't believe you Joe, but I needed to look it up, and there's definitely a significant difference. Here are the numbers for 1/2 ton trucks. 1937 spring rates: Front - 475 lb/in, Rear - 200 lb/in 1950 spring rates: Front - 315 lb/in, Rear - 190 lb/in For the front springs that's a significant difference. When my '51 chassis was assembled, I could barely move the front springs by jumping on the frame, and I'm 250 lb. The rears, I could move a bit just by pushing down on the frame standing on the ground. A '37 would definitely be like a rock in the front.
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
Thanks for pointing that out Kevin, I went back and changed the post. The '46 trucks have 260 front, 190 rear spring rate and pretty close to the same shipping weight. I knew GM lowered the rate at some point, just got my years wrong. My custom springs are around 250 lb/in.
When I first had the truck on the road, I could have left the shocks off, it was so stiff riding. I added teflon type material between each leaf to help them slide, it helped some, but not much. I then removed 3 out of the 7 total leafs and drove with 4 and the liner material for quite awhile. Running down I-70 in traffic at 70 mph got me thinking about the springs and what's going to happen if one breaks, so I ordered up four custom made new ones.
RBs36 truck will about like mine was, over sprung. The original engines are heavier then my late 250 is, so that will help, but a small block or late inline will take some weight off and then the ride starts getting harsh. I was at the point of adding lead weights inside the front frame rails till I talked with Detroit Spring.