Very low front suspension

[Napoleon Boot]

I've always struggled with the speed bumps around here, but today's the first time I've actually got under the car with a tape measure to see exactly what's going on, and what I found surprised me.

My 1971 Traveller is basically standard, but has an automatic transmission from a Toyota Starlet fitted, and the PO told me that the engine is mounted a bit lower than standard to get it to line up to the 1098 engine. Fair enough.

A few weeks ago, a particularly massive pothole pushed the driver's side bumpstop through the inner wing, which has led to me taking the wings off, tidying up and preparing to get the damage repaired.

What I've found is that the bumpstops are not only way too close to the top of the kingpins veritcally, they're not lined up with them, and I think the suspension needs to come up at least a couple of inches so that everything lines up properly (assuming that as the ride is raised, the front wishbones will pull inwards a bit).

From the sump to the road is four inches, instead of the expected six, and from the bottom of the gearbox to the road is only three inches, which explains the grounding on speedbumps!

I measured from the bottom of the elliptical hole in the flitch to the centre of the torsion bar as instructed in the attached picture, and it was ten inches, not the seventeen inches expected. It's such a big discrepancy that I'm wondering whether I'm misunderstanding the diagram.

94.jpg (53.54 KiB) Viewed 1103 times

Finally, I know it's not a scientific measurement as the wings just bolt on, but on the driver's side I can barely fit two fingers between the top of the tyre and bottom of the wheel arch (so about an inch), and on the passenger side it's only a bit better, say two inches.

The dampers appear fine, the ride in general is fine, and the rear suspension, was rebuilt a few years ago. It's just the front which appears to be much lower than it should be, and I'm wondering if I should raise the front by at least two splines to get another three inches of clearance. I've attached some photos, if anyone can advise I'd be hugely grateful, as all I have to go on is what I can find in archived threads and what I can find in reference books!

(Forgive the road dirt and flaking underseal in the pictures, this is the side I haven't cleaned up yet)

Seb

IMG_7910.jpg (1.03 MiB) Viewed 1103 times

IMG_7908.jpg (1.03 MiB) Viewed 1103 times

IMG_7907.jpg (415.38 KiB) Viewed 1103 times

[les]

If seen many drivers of low slung ‘sports’ cars go over speed bumps at 2 mph. One of these days I’m going to stop one and show them how to do it ! In your case moving the arm a spline or two should help. Not sure about the rear.

[Bill_qaz]

Can't fathom why your bump stop is so far inboard of the trunnion top. Even adjusting the ride height with the torsion bar, would that move it far enough inboard?
I had a similar pothole versus rust incident that pushed it through the inner wing.
Before and after repair pics but you can see the bump stop aligns with trunnion top.

20240914_184012.jpg (310.41 KiB) Viewed 1084 times

20250131_102243.jpg (1.45 MiB) Viewed 1084 times

[Napoleon Boot]

If seen many drivers of low slung ‘sports’ cars go over speed bumps at 2 mph. One of these days I’m going to stop one and show them how to do it !

Thanks Les! I've become quite expert at getting over them, each one requires a specific technique especially as the road has generally subsided randomly around them. This hot summer does seem to have caused a lot more subsidence as I'm scraping on bits of road that I wasn't before.

[Napoleon Boot]

Can't fathom why your bump stop is so far inboard of the trunnion top. Even adjusting the ride height with the torsion bar, would that move it far enough inboard?
I had a similar pothole versus rust incident that pushed it through the inner wing.
Before and after repair pics but you can see the bump stop aligns with trunnion top.
20240914_184012.jpg
20250131_102243.jpg

Thanks Bill, those pictures are very helpful, I can see that there should be several inches between the bumpstop and trunnion top - even if mine were aligned correctly, there'd still be no clearance at all.
I can't weld, so I'd better find a garage who will do it and ask them to raise the ride height at the same time. I've looked at videos and it appears relatively straightforward to undo the wishbone nuts at the front and turn it a spine or two but I'm wary of messing things up.

Seb

[philthehill]

The inner wing/Flitch panel is welded in place so is not movable like a wing so the drawing measurements shown above is a good indicator of how your suspension height is.
To get it accurate you need to look at BMC wksp drawing Fig 3 in Section K3. The suspension ride height is correct when there is a difference of 0.75" between the height of the inner pin and the outer pin of the suspension arm when you have three passengers and full equipment. The heights are measured on a level surface with all four wheels on the level surface.
Section K3 gives the instructions for measuring and adjusting the height of the suspension.

[Bill_qaz]

viewtopic.php?t=80120

May help

[Napoleon Boot]

The inner wing/Flitch panel is welded in place so is not movable like a wing so the drawing measurements shown above is a good indicator of how your suspension height is.
To get it accurate you need to look at BMC wksp drawing Fig 3 in Section K3. The suspension ride height is correct when there is a difference of 0.75" between the height of the inner pin and the outer pin of the suspension arm when you have three passengers and full equipment. The heights are measured on a level surface with all four wheels on the level surface.
Section K3 gives the instructions for measuring and adjusting the height of the suspension.

Thank you Phil, I've been studying that drawing in the workshop manual and intend to measure the difference between the inner and outer pin as soon as I can - I believe it should be 1 5/8" when the car's unladen.

Thanks for the link Bill.

Best wishes,
Seb

[Mervin]

Thanks for posting that "ride height" picture. I remember seeing similar, some years ago, when I refurbished the front suspension. I adjusted it to that dimension.
I can't remember where I saw that dimension and have not found it since. It was a different picture to that though.

[philthehill]

To get the suspension height correct on assembly I use a piece of flat board about 3" wide and long enough to reach from just above the eye bolt pin to the ground, place it sideways against the eye bolt pin, mark it off on the board and then measure 5-5/8" down the board from the top mark for the centre of the outer trunnion pin as it would be with the suspension disassembled, mark off on the board. I then drill through the board at the bottom marked point of the outer pin and insert a 3/8" UNF nut and bolt. The board can then be bolted to the outer hole in the thick suspension arm. With the bottom of the board resting on the floor the thick arm can be slid onto the cone of the eye bolt pin. The thick arm outer end will then be at the right height relative to the inner pin. Make sure that you compensate for any wear on the torsion bar splines or wear to the inside splines of the thick suspension arm. Even with NOS suspension parts the splines are not always tight.
Using the board makes life so much easier when assembling the Minor front suspension. It also helps as no two jacking heights are the same.
I do tend to set the drivers side a little higher as I am the only passenger in the car and therefore the car rides level. The lower of the two 3/8" bolts is the drivers O/S setting. I always check the height of the outer end of the suspension arm with the board before removing the arm so that it goes back exactly the same.

Suspension height board.jpeg (122.38 KiB) Viewed 498 times