Coil Spring Question

40 Chev · March 17, 2004, 01:25:02 PM

I'm doing a new frame for my 40 Chev, I've used MII for the front end the donor was a 77 Bobcat, my question is: should I use the original springs or should I purchase springs that were used on V8 Mustangs.

TIA
John

Bob Paulin · March 17, 2004, 03:40:35 PM

Quote from: "40 Chev"I'm doing a new frame for my 40 Chev, I've used MII for the front end the donor was a 77 Bobcat, my question is: should I use the original springs or should I purchase springs that were used on V8 Mustangs.

TIA
John

Take a peek here......

http://www.eatonsprings.com/m2coils.htm

Bob Paulin

Dave · March 17, 2004, 07:44:51 PM

I hate to argue with anyone about springs but when I did the old 34 I talked to everyone and got 2 hands full of different answers. I ended up buying chassis engineerings lightest spring they made. I put them in and tossed the old ones that came with my kit and it rode nice. Before I spent any money id try the springs you have. Its a B$%^h to replace em later but untill you really drive it its hard to get a feel for what you may need. I talked to heights at kzoo and they werent any help at all. I called JPL where I got all the stuff and they said thats the lightest spring we have.I talked to CE at kzoo and they told me they used the lightest spring they have so I bought em. Look at eatons 34 34 ford recomendation. Mine were 250's if i remember right. A lot different than what anyone else says I needed. I dont have a CE catalog handy or id look it up to be sure. All in all springs are fairly cheap if you figure what every thing else cost to build the thing so my way of thinking is if it takes 2 tries to get it right then so be it. Also you can run a little softer spring if you have an anti roll bar(sway bar for some)... Im waiting for softer springs for my coil overs right now. Its way to stiff and choppy. I think this set will be a no charge deal then if its not right ill try again...
My Nickle..
Dave

Mikej · March 17, 2004, 08:33:45 PM

It would be best if you weighed the car. Mine was 1700# on the frontend(BBC). Ended up using 600# springs. Tried 500# springs but they weren't enough.
Don't make the same mistake I did by cutting the coil before it had time to settle. It settled about an inch after I cut the springs :oops:

Charlie Chops 1940 · March 17, 2004, 08:58:39 PM

I've got a Heidts MII on the front of my '40 Chevy convert. I cut 2" out of the crossmember and added 2" to the hats just to get it at an acceptable ride heigth. I tried a couple differents sets of springs and shocks and finally ended up with a set of Pro-Shock coilovers. They've been in there for 12 or13 years, no problems at all. I've not been a big fan of coil-overs but these really filled the bill. Talk to Charlie at Pro-Shock if you decide to give that a try.

Charlie

Just another alternative

enjenjo · March 18, 2004, 12:32:11 AM

On my 47 Chevy, I used new 4 cylinder springs, with a coil cut off, and that worked just right. The mention of springs settling is correct. Every set I have used has settled at least an inch after a few miles.

40cpe · March 18, 2004, 09:34:20 AM

For what it's worth, I'll add my experience. In my '40 Ford with a 302 I used the 4 cylinder springs with 1/2 coil cut and it rode pretty well. Out of curiosity one day I put a set of 6 cyl springs in to try it. The 6 cyl springs jacked the front WAY up and rode very stiff. I can't imagine anyone needing V8 springs.

Dirk35 · March 18, 2004, 09:10:45 PM

FWIW, my donor car was a MII, 1974 with V6.

After I got the front suspension all in, I put most of it back together to check for fit. Its a 35 Ford PU, with a 302 and heads and stock intake for the mock up, C-4 tranny, but no pulleys or water pump or water in the radiator, in it and all the sheep metal on for fit. It still sat way high, and even with me jumping on the front of the frame horns, it doesnt bounce up and down like a normal vehicle. It feels way too stiff. I weigh 190lbs (you skinny people hush!) and I can bounce a normal car pretty good by bouncing on the bumper. But my 35, I cant even get it to flex the front suspension.

My suggestion, go with a lighter spring to start off with. Ill probably be getting new ones from Eaton eventually, but I got more important things first, like actually being able to get it to move!

GPster · March 19, 2004, 10:24:03 AM

Dirk35, I got to thinking about your problem last night. I have a MOOG spring catalog and I looked for an application that was for a spring that was the same diameter as the Mustang II/Pinto springs but of a lighter diameter wire (?) but all reference to anything lighter has been dropped to the point that I can't even cross it to an application. Do you have any friends that are into "dirt track" racing? Pintos were popular for the 4 cylinder classes. Maybe someone bakes a light duty coil for the inside front wheel application? GPster

Dirk35 · March 19, 2004, 11:29:57 AM

Thanks GP. Im not worried about it sitting nose bleed for now. I figured Id just get a set from Eaton later down the road after I see more of how its going to set and ride. Heck, I figured Id probably even cut a coil until Im actually ready to put more dough into actual looks instead of just getting it going.

But, Ill try to file that inot the recesses of my mind for later use when I get to that point.

GPster · March 19, 2004, 01:26:27 PM

Dirk, they way I understand the spring technology They are like a torsion bar that is just coiled. Cutting a coil to shorten the spring is going to make the length of the torsion bar shorter which will make it stiffer. To have a bar that is less stiff you will need on that has the bar made of a material that has a smaller diameter. You might even look towardsthe springs off of a set of struts. If Bob Pauline is reading he can probably explain it better and if I'm wrong he has a way with words that don't make be realize how dumb I am. Might put in mind air-bags to replace the springs altogether. GPster

tonto1 · March 20, 2004, 08:46:33 PM

I've got a brand new set of Chasis Engineering 300#'s you can have just for shipping.

jaybee · March 21, 2004, 09:18:33 AM

Quote from: "GPster"Dirk, they way I understand the spring technology They are like a torsion bar that is just coiled. Cutting a coil to shorten the spring is going to make the length of the torsion bar shorter which will make it stiffer. To have a bar that is less stiff you will need on that has the bar made of a material that has a smaller diameter. You might even look towardsthe springs off of a set of struts. If Bob Pauline is reading he can probably explain it better and if I'm wrong he has a way with words that don't make be realize how dumb I am. Might put in mind air-bags to replace the springs altogether. GPster

Nope, you're right on target in terms of how springs work.

Dirk35 · March 22, 2004, 01:34:06 PM

GP, Im pretty sure your right on target with how they work. Im not cutting a coil to make it ride better, Im cutting a coil to get it to sit more right UNTIL I can afford to actually buy the right thing to make it ride right. Think free here! :oops: :oops: