Air bags with leaf springs?

[mt2man]

Hey all I have a 1977 Toyota corona I really want to put on air. The front set up is ideal and easy for air bags it's the rear I'm not sure.

It's leaf springs at the back, if I remove all the helper springs and installed an air bag between chassis and axle would the single leaf give enough location? Would it drop enough with leafs removed or will I need lowering blocks too?

I've seen you can get air bag assisted for trucks with leaf springs for when you have a large load in the back, but I'm aiming for low ground clearance as standard and the ability to raise if needed/wanted.

Any advice?

[stealthstylz]

Airbags only raise the ride height. You need to get it sat how you want at full drop so decamberred springs/lowering blocks. Personally I'd look at converting to ladder bars or 4 link.

[mt2man]

With the other leafs removed surely it will drop substantially?

Really didn't want to go into 4 link etc, it's far too much work! Haha

[colnerov]

Hi, either with the other leaves removed or lowering blocks fitted it will be easy for the axle to wind up the spring and so produce axle tramp on even moderate acceleration. Radius arms will help, ladder bars will stop this.

Colin

[mt2man]

That's what I was trying to ask, will a single leaf cause axle tramp?

Would an anti roll bar or some kind of panhard bar provide enough location with a single leaf?

[Dez]

you can do it, but itll be sh1t. its called bag over leaf and is done a fair bit on american stuff. it rides badly and the springs can wind up as said, as they're not stiff enough to locate the axle properly.

the best way to do it is an unequal length 4 link, like say on the back of a lada. two long lower links from the original front leaf spring mounts to brackets added to the axle, then two shorter ones tucked inside the chassis rise further back. youll need to add some re-enforcement to the rails, maybe an extra crossmember, but its pretty straightforward and will handle 100X better.

[colnerov]

Hi, an anti roll bar as its name suggests reduces roll i.e. lean in a bend. A panhard bar stops side ways movement of the axle, and is the fifth link in a 5 link set up.

Colin

[mt2man]

What do people think about removing a leaf, installing 2" lowering blocks and then buying a kit like this and modifying it to fit?!

pages.ebay.com/link/?nav=item.view&alt=web&id=181680170347

They're made mainly for motor homes to handle the weight, but if I can get the car very low on leafs then I can raise it using the air bags?

The ride should be much like standard, if not a little stiffer due to the bags?

[Dez]

that question has already been answered.

i also see no way on inflating the bags in that kit, meaning you'll need a compressor, tank and valve block as well.

there other things to consider. taking out leafs softens the suspension. as does decambering. lowering it by doing this means you blow through the available travel very quickly, meaning a crashy ride. when ive lowered leaf spring cars ive always had to add leafs to stiffen it up to make the ride acceptable, but theyll still flex in the other directions mentioned, as its both the amount of leafs in the pack and the curve of them that make a spring pack stiff.
putting a bag on top doesnt fix this, it just masks the problem with a second spring.

the proper way to do it is get rid of the springs, fit some solid form of axle location, then re-spring it with the bags as the sole form of springing.

there is one other way of doing the axle location, its called a track locator, but can be very hit and miss handling wise depending on how long the front half of your existing springs is, as it basically replaces those with a diagonal link for lateral location.