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Spitfire Spitfire Air Shocks
- Thread starter roofman
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Trevor Triumph
Jedi Knight
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Some people have used air shocks to restore the ride height with out re-arching the rear spring, I think. The problem is, the shock bolt takes the stress rather than the spring bolts. Some friends have added Corvette air shocks and it works well for a while, but they notice stress in the body around the gas tank. In fact, due top the air shocks the gas tank began to leak- gas running out, not a few drips on the garage floor. I think more has been written about this earlier- some years ago.
Others may remember more about this.
T.T.
Others may remember more about this.
T.T.
If you were to ask this question over at the NASS site, you will get some more answers.
If I understand correctly one problem inheirant with the design of the rear suspension in the Spitfire is what is known as the "Spitfire lean" where the back of the car is noticeably crooked.
Some people have corrected this by installing air shocks, and by modifying them so that they can be individually inflated, the car's ride can be straightened out.
Personally what I think happens, is that most of the time these cars are driven with only the driver on board, and when your gross design weight of the vehicle is approached with only that driver,over time the spring will weaken and take a "set" on the drivers side. One fix is to swap the spring end for end, another is to have the spring rearched, still another is to replace the spring, and fourth is to jack up the offending side with the air shock.
If your car is not leaning then no further action is necessary. If you are looking at a car that has advertised an air shock install, then watch for rear suspension issues. The car was designed to be hung from it's differential in the back. To take weight with the shock towers requires a redesign of the force paths.
just my two coppers
If I understand correctly one problem inheirant with the design of the rear suspension in the Spitfire is what is known as the "Spitfire lean" where the back of the car is noticeably crooked.
Some people have corrected this by installing air shocks, and by modifying them so that they can be individually inflated, the car's ride can be straightened out.
Personally what I think happens, is that most of the time these cars are driven with only the driver on board, and when your gross design weight of the vehicle is approached with only that driver,over time the spring will weaken and take a "set" on the drivers side. One fix is to swap the spring end for end, another is to have the spring rearched, still another is to replace the spring, and fourth is to jack up the offending side with the air shock.
If your car is not leaning then no further action is necessary. If you are looking at a car that has advertised an air shock install, then watch for rear suspension issues. The car was designed to be hung from it's differential in the back. To take weight with the shock towers requires a redesign of the force paths.
just my two coppers
PS in looking at your car, you would gain a lot of things by lowering, by either cutting or replacing your front springs to get the nose back down where it belongs and straitening out your steering sytem.
BL complied with headlight hieght regs by jacking up the nose with long springs.
Early springs are a bolt in and make a noticeable difference while driving.
BL complied with headlight hieght regs by jacking up the nose with long springs.
Early springs are a bolt in and make a noticeable difference while driving.
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I'm with Steve on this. I won't say it's never occurred, but I don't think I've ever seen the "dreaded lean" on a US-spec. Spitfire before the 1974 model year; that was the year the rear frame extensions were added for support of the rubber overriders. Subsequent rear bumpers got yet heavier, and I suspect that the swing spring just wasn't quite up to the task of supporting the wider track AND heavier overall weight of the rear end of the car.
I also happen to suspect that the air shock setup is more a band-aid than an upgrade. There's enough stress on those shock mounts as it is. In fact, the original Herald chassis (from which all these cars were derived, of course) had much less sturdy upper shock mounts. One of many upgrades to the chassis -- originally to accommodate the Triumph six-cylinder but adopted across the entire range -- was to "bridge" those upper rear shock mounts and reinforce the mounting area for the differential.
I also happen to suspect that the air shock setup is more a band-aid than an upgrade. There's enough stress on those shock mounts as it is. In fact, the original Herald chassis (from which all these cars were derived, of course) had much less sturdy upper shock mounts. One of many upgrades to the chassis -- originally to accommodate the Triumph six-cylinder but adopted across the entire range -- was to "bridge" those upper rear shock mounts and reinforce the mounting area for the differential.
myspitfire
Jedi Warrior
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When the fat lady(passenger side)) sings you'll know everything has straightened itself out :banana:
But seriously a new Moss spring AND air-shocks(individual Shraeders) is the best answer as i did.
PS;You could also think about removing the heavy spare or putting a weight in the RIGHT side in the boot to compensate.
But seriously a new Moss spring AND air-shocks(individual Shraeders) is the best answer as i did.
PS;You could also think about removing the heavy spare or putting a weight in the RIGHT side in the boot to compensate.