440 '48 Plymouth Coupe

[racingsnake440]

That really cleaned the frame up! And it will make mounting the straight axle a lot easier now! Nice work!

Thanks, still got to blend the bottom of the frame into the box section and plate over the joins but happy with how it's looking.

John, this is the first time I've put new frame rails on a car - well second if you count the ones I cut back off...

[racingsnake440]

Front axle on and back on its wheels - well it would be if the rear wasn't on jackstands because the ET Streets lose air... Steering next

[1946Austin]

Nice stance! Hope it stays up in front once the engine weight is sitting on it!

[SuperBuickGuy]

out of curiosity mostly - I've done better then a dozen FJ40 landcruisers, and my 1st fix was moving the shackles to the rear of the spring so that they stop following every divot in the road.... is it typical of gassers to have the shackles in the front, if so, why? - the reasoning behind the moving the shackles back is stops the shortening of the spring when one tire hits an obstruction (think S shaped spring, but only on one side).

[racingsnake440]

Nice stance! Hope it stays up in front once the engine weight is sitting on it!

Thanks! I expect it'll drop down a bit but not a whole lot - I've only got a couple of leaves in the springs at the moment and will be putting the rest back in when the car is fully assembled.

As for shackles on the front, I think the majority of gasser style cars are like that although I've also seen plenty with the shackles at the back. Don't know if one's better than the other but my '47 had the shackles at the front and drove great so I've done the same on this one.

[SuperBuickGuy]

Thanks! I expect it'll drop down a bit but not a whole lot - I've only got a couple of leaves in the springs at the moment and will be putting the rest back in when the car is fully assembled.

As for shackles on the front, I think the majority of gasser style cars are like that although I've also seen plenty with the shackles at the back. Don't know if one's better than the other but my '47 had the shackles at the front and drove great so I've done the same on this one.

and jeeps have as well (shackles in the front). anyway, it's merely something to consider

[STINEY]

In the 90's a shackle relocation kit was quite popular for the CJ's and YJ's, improved the ride a BUNCH.

Still, having put 100,000 miles on my '86 CJ7, it wasn't too bad in original configuration. Stiffer springs made it unbearable, it danced on every bump.

[1946Austin]

Most the straight axles I've done I put shackles in the front and had no issues. I put them in the rear on the Austin simply because the stock axle had them in the rear and I was able to reuse the stock mounting point and fab new in the front. It works just as well as the others I've done. Not sure there is a better way, as I see most factory setups have front shackles.

[SuperBuickGuy]

Most the straight axles I've done I put shackles in the front and had no issues. I put them in the rear on the Austin simply because the stock axle had them in the rear and I was able to reuse the stock mounting point and fab new in the front. It works just as well as the others I've done. Not sure there is a better way, as I see most factory setups have front shackles.

Chevrolet trucks have the reverse. It's a choice, but given a preference, I'd always put them in the back.... of course, how arched the spring makes a huge difference. On my landcruisers, the difference was above 60 mph - of course, a stock land cruiser (FJ40) can't do 60 - but the difference was substantial. With the shackle on the front, the distance from the front of the spring to the axle can change. That change, in essence, changes your wheelbase on one side only - thus your car goes the direction of the spring that has the most deflection. On a smooth dragstrip, it should never make a difference, but on streets - it really can get to be a handful, especially if you have a super short wheelbase. In short, you got lucky my friend

A lot of people leave the front shackle because you can do a shackle lift on the front without causing terrible driveshaft angles. Because most shackles are made of stronger steel and boxed, you actually get better handling then before.... still, the shackle should always be to the back.

[zombie289]

Looking good Nick, You've come quite a ways since we hacked the firewall out the way...

[racingsnake440]

Looking good Nick, You've come quite a ways since we hacked the firewall out the way...

Cheers mate - it's getting there.

Regarding the shackles, I've had a couple of older trucks and Land Rovers with shackles at the front and they all drove ok. Interesting that running the shackles at the back improved the ride on Jeeps - I may try that on a future project but I think the weight of the 440 should help soften the ride on this one.

[Scott Liggett]

That thing should haul butt even if the 440 is kept near stock.

[Huskinhano]

I'm not a suspension expert by any means. I'm in the process of doing some suspension work on my 66 Mustang. Before I statered I bought a book on the topic. It's interesting on how much a simple thing can do. For instance did you know leaf spring act as anti roll bar? If you ever notice, rear leaf spring cars typically don't run a rear anti roll bar while coil sprung cars run a nice beefy one? On the Mustang site I hang out on the road race guys don't run a rear bar. And as it's been mention as leaf springs compress, they grow in length. The OEMs took advantage of this as a cheap rear steer to make a car turn sharper.

I'm siding with you on putting the shackles in front. The reason is the fact that the leaf will "grow" as it's compressed. I'm thinking this will increase caster and keep the car more stable while braking or turning. Ford also used cross steer on the solid axle fronts to reduce bump steer back in the day.

[1946Austin]

Chevrolet trucks have the reverse. It's a choice, but given a preference, I'd always put them in the back.... of course, how arched the spring makes a huge difference. On my landcruisers, the difference was above 60 mph - of course, a stock land cruiser (FJ40) can't do 60 - but the difference was substantial. With the shackle on the front, the distance from the front of the spring to the axle can change. That change, in essence, changes your wheelbase on one side only - thus your car goes the direction of the spring that has the most deflection. On a smooth dragstrip, it should never make a difference, but on streets - it really can get to be a handful, especially if you have a super short wheelbase. In short, you got lucky my friend

A lot of people leave the front shackle because you can do a shackle lift on the front without causing terrible driveshaft angles. Because most shackles are made of stronger steel and boxed, you actually get better handling then before.... still, the shackle should always be to the back.

The newer Chevy trucks might have rear shackles, but all the early Chevy trucks through the 50's used front shackles. Also all; the big major chassis builders use front shackles. Here's Jim Meyers Chassis setup:

[Deaf Bob]

Huskinhano posted: For instance did you know leaf spring act as anti roll bar? If you ever notice, rear leaf spring cars typically don't run a rear anti roll bar while coil sprung cars run a nice beefy one

I have a t-bird rear bar on the back of my 57 Chevy Sedan Delivery. Best thing I ever done.. I can get my hand flat between fender lip and tire.. Can hit corners real fast and have NO RUBBING..
Alot of dualies/camper haulers have sway bars .. Be surprised how much they help.. Am going to put one on my Suburban as well. That thing sways so much whomever rides with me feels like puking.. Except when I have a full tank of gas...