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Discussion Starter · #1 ·
OK, now that the holidays are over, back to the project, I have a F1 ford axle now with disc brakes, I have removed the orig. front end parts, NOW, I'm back to looking at springs again. I have measured where I want the spring's to sit on the frame, and I'm at 30", but how much drop should I take into account once I put wait on them, and should I go with 30" springs are maybe shorter to accommodate for weight and compression?
 

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that's a tough question. If I were doing this I would tack weld the shackle end and put the jacks under it and see what your shackle angle is with the weight on the axle. Do you have the motor in the car and all? the best situation is if you have the shackles to the back of the axle so you can adjust if needed.
mario
 

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Discussion Starter · #3 ·
The motor is in, I think I will follow your advice and tac in the hangers and see what they do. I might go with 29" springs, If the compress more than an inch or so im still good. I just want to make sure I get that 45 deg on the shackles.
 

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The motor is in, I think I will follow your advice and tac in the hangers and see what they do. I might go with 29" springs, If the compress more than an inch or so im still good. I just want to make sure I get that 45 deg on the shackles.
I'm thinking 45 might be a bit much without compression. I would start with just over 90 to 60. You can ask Steve his opinion. He's the pro around here.
mario
 

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Thank you Mario, but the PRO remains in the name...... I'm still on my learning venture in the hot rod builder world..:) but nothing better then a bunch of good old hot rod folks to help figure out what's works best for each individuals ride.
My thought on front spring is one I like the shackles up front, but have not shown any baring on ether front or back. However when it comes to angle, it may be a more scientific then we think. Angle seems to affect a few things, one being spring weight, the other articulation. I think both are important were they can or may lead to a better/safer ride quality.
I like past ninety degrees forward, when the shackles are mounted front or rear.
My thoughts if you start off the shackle in the direction it's going to swing there's less stress when the spring pushes the shackle threw its arc. Now when the vehicle lifts, the shackle will want to come back to ninety but with no chance to swing negative. So some applications may take more forward angle then others. So we most likely have to keep the shackle from going to far forward hitting or bottoming out on the frame and when spring unloads, not swinging to a negative arch stressing the shackle to return to its curb position.
I'm not sure how one would calculate at what point in the arc what the spring weight is. Think of all the variables, that would affect this. Weight of vehicle, motor location, curb stance, shackle location, and length, shock length, and the list goes on.
I like to tack the the shackle mounts in place and try to simulate different scenarios with tie down straps and jacks for load and unload.
I guess what I'm saying, short of sounding like a politician that had said a lot with out giving a direct answer :D:D we can trial and error, follow what works for others with a similar application, and post questions, pictures, and share your results.
 

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Steve, maybe you should run for office. Ha Ha just kidding. I think you said it right you need to have the weight on the springs to determine shackle mount placement. I would mockup motor & tranny in chassis and set axle center and temporarily tack or clamp spring mount to chassis then,with the shackles mounted on the other end of the spring along with shackle mount temporarily clamped or tacked to the chassis with shackles angled. Then get a couple buddies stand on the front of chassis and start up and down movement to simulate suspension flex this will give you a better idea of where the shackle mount placement should be and also at the same time you can put a yardstick beside chassis rail and make upper and lower travel marks/ measurements this will also give you a better idea on shock length needed for your application. Hope this might help you out a little. Andy
 

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Thank you Mario, but the PRO remains in the name...... I'm still on my learning venture in the hot rod builder world..:) but nothing better then a bunch of good old hot rod folks to help figure out what's works best for each individuals ride.
My thought on front spring is one I like the shackles up front, but have not shown any baring on ether front or back. However when it comes to angle, it may be a more scientific then we think. Angle seems to affect a few things, one being spring weight, the other articulation. I think both are important were they can or may lead to a better/safer ride quality.
I like past ninety degrees forward, when the shackles are mounted front or rear.
My thoughts if you start off the shackle in the direction it's going to swing there's less stress when the spring pushes the shackle threw its arc. Now when the vehicle lifts, the shackle will want to come back to ninety but with no chance to swing negative. So some applications may take more forward angle then others. So we most likely have to keep the shackle from going to far forward hitting or bottoming out on the frame and when spring unloads, not swinging to a negative arch stressing the shackle to return to its curb position.
I'm not sure how one would calculate at what point in the arc what the spring weight is. Think of all the variables, that would affect this. Weight of vehicle, motor location, curb stance, shackle location, and length, shock length, and the list goes on.
I like to tack the the shackle mounts in place and try to simulate different scenarios with tie down straps and jacks for load and unload.
I guess what I'm saying, short of sounding like a politician that had said a lot with out giving a direct answer :D:D we can trail and error, follow what works for others with a similar application, and post questions, pictures, and share your results.
+A1 well said steve.
 

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Thank you Mario, but the PRO remains in the name...... I'm still on my learning venture in the hot rod builder world..:) but nothing better then a bunch of good old hot rod folks to help figure out what's works best for each individuals ride.
My thought on front spring is one I like the shackles up front, but have not shown any baring on ether front or back. However when it comes to angle, it may be a more scientific then we think. Angle seems to affect a few things, one being spring weight, the other articulation. I think both are important were they can or may lead to a better/safer ride quality.
I like past ninety degrees forward, when the shackles are mounted front or rear.
My thoughts if you start off the shackle in the direction it's going to swing there's less stress when the spring pushes the shackle threw its arc. Now when the vehicle lifts, the shackle will want to come back to ninety but with no chance to swing negative. So some applications may take more forward angle then others. So we most likely have to keep the shackle from going to far forward hitting or bottoming out on the frame and when spring unloads, not swinging to a negative arch stressing the shackle to return to its curb position.
I'm not sure how one would calculate at what point in the arc what the spring weight is. Think of all the variables, that would affect this. Weight of vehicle, motor location, curb stance, shackle location, and length, shock length, and the list goes on.
I like to tack the the shackle mounts in place and try to simulate different scenarios with tie down straps and jacks for load and unload.
I guess what I'm saying, short of sounding like a politician that had said a lot with out giving a direct answer :D:D we can trial and error, follow what works for others with a similar application, and post questions, pictures, and share your results.
Steve,
I have front shackles on my 35 and its a handful to turn with the old traditional front to back steering box and drag link to the left front steering arm. So I can't really blame the front mounted shackles entirely. But I did notice that the use of front leafs on trucks over the years and they have mounted the leafs at the rear of the axle. I can't help but think that front mounted shackles may sway side to side more than a fixed leaf mount on any hard pressed turn. I was curious what you thought about this theory. I'm not a chassis builder but I try to follow good examples from other's experience.
Anyway I mounted the leafs with the shackles to the rear on my mg for the reason I wrote above.
mario
 

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Discussion Starter · #9 ·
Thanks guys, I love reading your responses!! This will be my first shot at making a Gasser, although I have years of experience when it comes to building Hot Rods. I cant wait to put this together and see what the out come will be. I have been reading allot about gasser's here and numerous other places, I came across an article that mentioned using a Jeep Cherokee 2 wd front axle, any thoughts on that, it is a straight axle with no drop, I was wondering if that would work on my 55 Fairlane or any Gasser for that matter!?
 

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I know a couple guys using the Jeep 2wd Cherokee straight axles. They have good points and one bad point. The good is they are modern, so better materials than very old donor axles, plus they are stock with disc brakes, and parts are readily available. The only bad point is they are asthetically a little bulky looking, with very large spindle ends that aren't real pretty. The ends are separate knuckles, not a single kingpin that goes through like a traditional straight axle. These ends do make it much stronger, and mechanically better, if you don't mind the size. They also have a front tierod, instead of the typical rear, but that's not an issue to me.
Here's a picture of what they look like with all the factory mounts. They need everything stripped off to use them with parallel springs.
 

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If you use a drag link with the box behind the centerlne of the axle, you need to have the shackle to the front and the solid spring mount to the rear. With a drag link and the shackle to the rear, when the axle goes through it's travel/arc like going over a bump, it changes the length of the spring from the centerline of the axle to the shakle. This change will show against the solid unchanging length of the drag rod/steering box, and causes the steering to be affected. If the rear of the spring is solid mounted, the relationship of the drag link to the length of the spring does not change with the axle travel, and the steering remains much more stable. The secondary affect is more stabiity of the axle going over bumps. Again the relationship of the axle/drag link does not change averting rapid steering movements. I use a cross steering link system and I think that there is minimul to no affect imparted thru the steering system whether you have a front or a rear mounted shackle. Rereading this whole reply, I think I just said the same thing twice. Heh. That's OK. That's OK. I'm fine. I'm fine. Lol. Lol. Markus O'Repeaticus Markus O'Repeaticus
 

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I was looking at those trailer springs as an alternative for what I was using. Only difference was they were shorter in length which would have shortened my frame a bit to accommodate the
tilt nose a little better. I think they could work fine.
mm
 

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I just grabbed that picture off the internet Steve, but I think that's a transfer case for a 4wd.
Hey Vall..... How do you THINK Steve would know the DIFFERENCE!!!! L o L.....L M A O ..... Haaaaa!!!!!!!
 

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I looked at trailer springs for my Austin axle, but couldn't find any that were the right length. I also needed shorter to stay inside the frontend, and allow the tilt to work. I ended up going to the local spring builder and taking my springs to them. We removed the main leaf, and one leaf below it, then they made a shorter main of 29.5" to work.
I may someday remove one more leaf, just to allow more spring travel under acceleration. I think more travel would plant the rear tires better if I also adjust my coil overs in the back to drop the rear a little too.
 

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I think the frame on the mg is going to present a challenge to get the tilt to work right. I may have to cut into the front roll pan to get it to tilt over the frame work. Shorter springs would have cured that. Just another work around that's all.
Mm
 
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