on a heidts or tci tubular lower a arms what is the measurements from the center of the ball joint to the center of the air bag. I have a 39 chevy when the car is down the bag touches the lip of the frame. and when the car is up the bag touches the upper ball joint. Please give me your input
what size bag? is the bottom of the bag mounted to the lower control arm directly? or is there some standoff below the bag.. my experience has been that the bags on MII need to be DOWN as low as possible.. and you need to run the smallest bags possible
the bag with out air is approx 6 inches across, there is a plate welded flat on the top of the tube a arms and the bag mounts directly to the a arm. does the cup on the top of the bag need the bolt through the original shock hole to keep the cup / bag from moving tilting as the a arms go through there arc up and down?
The pics posted above are about as good as it's gonna get on a MII front end. Take note that the lower bag mount is pretty damn close to being in line with the lower arm inner pivot, that will keep the bag from pushing out when the vehicle is lifted. I will go so far as to push the upper mount out a bit so that the bag lines up better at half travel. That way the bag will be slightly out of alignment when lowered or raised instead of being way out of whack at full lift. The problem with bagging a MII is that the spindles are so short that no matter where you put the bags the bag it is compromised when trying to get anything moer than 5" of total travel. Also the MII doesn't have room (in most cases) to fit the proper sized bag. I would never run the bag pictured above in anything larger than a Toyota pickup, it's just simply not enough volume for a full-size vehicle.
Those are Firestone 2600s. More than enough to do the job. That car finished only took 60psi to achieve ride hieght and after doing my math had an effective spring rate of 320 lb/in.
THANK YOU ELpolacko, i will play with the lower position of the bag and i can make a upper bag mount. my front end has and needs more travel than the one in your picture it lays all the way down and locks up higher thats why the upper ball joint is near the bag
The car pictured had about 7-8 inches of suspension. And it sat about 2" off the ground fully deflated. I never let my cars touch the ground, saftey reasons. I don't like getting sued.
It looks to me that the Firestone part number for that bag is a 255c, if so it is not rated at 2600lbs and is a compromise on a vehicle that size. If it is in fact a 224c then, yes it is a large enough bag for most applications. I said that the installation was just about perfect and I do give kudos to the builder, I'm not trying to make enemies. I have seen a few MII front ends that worked out well, but all of the MII stuff that I have encountered was tollerable at best.
http://www.firestoneindustrial.com/pdfs/industrial/datasheets/IMPERIAL_PDF/EMDG_255-1.5.pdf http://www.firestoneindustrial.com/pdfs/industrial/datasheets/IMPERIAL_PDF/EMDG_224.pdf Either one is perfectly capable of supporting the sub 2000 pounds or the average 40-50s car. I rarely let the installed spring exceed 5" at ride height. As you can see even the 255 is holding 1100 pounds each at 60 psi. Given the position of the air-spring that can translate into 15-1800 pounds of force on the front suspension, well within the bounds of these cars. Even to push this to the extreme, at 100 psi and a 5" installed height yields 1800 pounds of force per each and that would net you well over 3000 pounds of capacity on the front alone! This car had a near perfect 50/50 weight distribution and barely tipped the scales in at 3200 pounds with the driver. It works very well and been reliable for years and has returned many smiles from it's owner. Yes, I have seen plenty of hacked air-spring jobs that didn't even pass for tolerable. I don't do hack.
Don't think for one second that I think that your work is hack-work. I have made that point clear already. I am throughly impressed that you would even go through the trouble to research the proper bag for that application, I don't see that much effort put into bagged cars very often. I personally don't like the way that the MII drives nor do I like the way that the small bag rides in comparison to the larger 224c part. When I see the 255c part being used in a "one size fits all" mentality I will always question its use.
I move the bag in more and toward the tie rod (rack) and trimed the lip on the frame. THe bag clears so now i will weld the frame lip
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