Technical Ladder bars with Z frame?

I’m setting up my deuce frame with a Z. Is it ok to have the ladder bars point down so much since the frame will be Z?

 

This is a mock set up of the rear end. You get the idea how the ladder bars will point down. Also I haven’t grafted the Z yet.

 

Do an online search for "instant center calculators" That should give you some good info. I had it in one of my old posts but I can't find it.

 

Basically, for a car to drive okay on the street, things are best parallel with the ground.

Dirt cars, drag cars, rock crawlers, amphibious vehicles and tractors my be different.

 

I agree with parallel to the ground, it’s how I’ve set things up before. I’m considering triangulated set up......

 

I ran into the same issue when I kicked the rear of my truck. The only solution I could come up was to move the bar mounts, under the cab, up as high as I could without interfering with the floor too much. I fabricate my own mount as the ones from Socal and Pete &Jakes just didn't cut it.

 

If the frame is blocked to ride height isn't the cross member awfully close to the ground? Its the axle to ladder bar pivot that matters, you'd have to raise the bar pivot point to get to level to ground, i.e. match c'line of axle.

 

Don't understand why anyone would want to build a car without sufficient ground clearance ,just makes no sense to me ....

 

I understand your confusion, like I don’t understand why people give an opinion when one isn’t asked

 

I felt the same with this style k member. I thought about raising the bar pivot for ground clearance and to level the ladder bars. I think I’ll go that route. The “loop” of the crossmember is the lowest point. Cutting that off would give me clearance and allow me to level the ladder bars.

 

Exactly what I’ll do, thanks

 

I would check the drive line angle you will have, also.

 

I mocked that up already. That balance because I’ll be raising motor and tranny for clearance

 

Do you have room under your seat to raise the ladder bar pivot point too? All you'll need is a bump in the floor. Would make good use of wasted space.

 

Yes plenty of room, it’s a roadster body.

 

Here’s the front cowl

 

I'm no suspension expert however the ladder bars need to point up or be horizontal to be geometrically correct and give you anti-squat with the correct amount of pinion angle at ride height. Pointing them down will cause the car to 'squat under load' which in turn can cause the rear tyres to easily unload. The pinion will point down. The front pivot point needs to correspond horizontally with centreline of housing at ride height.
With anti-squat built in and bars pointing up at the front up, the wheels have a tendency to turn the axle in the opposite direction. This motion causes the bars to push the car up.
With them pointing down the opposite occurs and the rear drops.
Race cars can have 1-2 degree down angle

 

I am a suspension expert, and you are indeed correct.

 

the thing I learned when I built my hotrod is the lower you go the more problems you'll have. seems like you're ground clearance will be 4" ? Will you be running mag wheels with low profile tires?

 

Well I guess you told me ..LOL

 

40s style wheels with American classic Bias ply look a like radials. Yes about 4inches

 

Sorry I wasn’t trying to be rude or condescending, I wanna keep my post about suspension set up. The more these guys teach me, the more info I can pass to younger guys to keep this tradition going.

 

Is this an underslung chassis?

 

At 4" ride height, you will be a minimum of 2" below the scrub line.

 

Looks like you're trying to build a '32 Ford that will "lay frame", which is crazy.
4" of ground clearance on a street driven vehicle is crazy.
So you might as well go crazy the rest of the way and build an under-slung frame from scratch instead of butchering the frame you have.
And I almost forgot, I actually enjoy watching people "color outside the lines", so to speak, but if you expect to show a non-traditional build style on this website and not get flamed, well, that's crazy too.

 

I've done several 32 chassis with kicked or Z'd rear frames and they've all run ladder bars but I uses a straight front bar and not a dropped one. I've never had any problems.

 

That’s what I’m working on, a straight bar. How tall of a Z did you make?

 

Chassis will be above the axle.

 

Please refer to post #10....