1937-1957 Buick Oldsmobile Pontiac suspension upgrade
(→Front suspension) |
(→Front suspension) |
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As you can see in the pics, the '58 control arms are more substantial than the '41. However, all the dimensions are the same. | As you can see in the pics, the '58 control arms are more substantial than the '41. However, all the dimensions are the same. | ||
| − | [[image:58 pontiac 41 pontiac lower control arm s.jpg|frame|none|The '58 Pontiac control arms are more substantial than the '41's.]] | + | [[image:58 pontiac 41 pontiac lower control arm s.jpg|frame|none|The '58 Pontiac control arms are more substantial than the '41's, but the dimensions are the same.]] |
The upper control arm mount is a fairly simple fabrication. If you have a pre-50's car, the upper mount will differ from this article. The pre-50's had the lever action shock, therefore no upper shock mount. On both of our tested conversions ('41 Pontiac and '49 Olds) we fabricated the mounts out of angle iron. We used ¼ in. 3x3 angle iron on the Pontiac, and added 2 gussets. On the Olds, we had some 3/8" 4x6 angle iron, so only added one gusset. | The upper control arm mount is a fairly simple fabrication. If you have a pre-50's car, the upper mount will differ from this article. The pre-50's had the lever action shock, therefore no upper shock mount. On both of our tested conversions ('41 Pontiac and '49 Olds) we fabricated the mounts out of angle iron. We used ¼ in. 3x3 angle iron on the Pontiac, and added 2 gussets. On the Olds, we had some 3/8" 4x6 angle iron, so only added one gusset. | ||
| − | [[image:49_olds_upper_mount_1.jpg]] | + | [[image:49_olds_upper_mount_1.jpg|frame|none|Caption goes here.]] |
| − | Note in the pictures how the front mount is higher than the rear mount. | + | |
| − | Be sure the frame is level side to side and has the correct front to rear angle that you want. (with 15 inch wheels, my spindle center was 12.5 inches off the ground. I blocked the frame, so that when the lower A was level, the spindle was 12.5 in up) | + | Note in the pictures how the front mount is higher than the rear mount. This sets up the anti dive angle. Up to 10 degrees is fine, as long as the upper ball joint is not in a bind. Be sure the frame is level side-to-side, and has the correct front-to-rear angle that you want. (with 15 inch wheels, my spindle center was 12.5 inches off the ground. I blocked the frame, so that when the lower A was level, the spindle was 12.5 in up). |
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| + | Even a small error here will be costly. It takes ½ inch of shims to adjust 1 degree of camber. If you need to put additional shims on the rear of the bracket, to increase caster, and can't take enough out of the front to keep the camber static, you will have to cut it loose and start over. Unfortunately, you can’t do a full alignment until it is totally finished, and basically driveable. So, get this part right. If you have any doubts, shade towards the positive camber side, as you can add more shims later to move it towards negative. Likewise, move the upper mount to a position about 3/4 inch behind the plumb line for the spindle, to set up at least 5 degrees of caster in the neutral position (neutral being the static position as mocked up, before final alignment). | ||
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| + | If you intend to add power steering, shoot for 6 degrees in the neutral position, but don't get the uppers so far behind the lowers that you put the ball joints in a bind. In this situation, holes were drilled in the bottom plate of the angle iron, and, when it was mocked up, I drilled thru the frame and bolted it up with 3/8 inch bolts. This was strong enough to allow for assembly of the entire front end, with springs, put the wheels and tires on it and set it on the ground. Everything was double-checked, then torn down and welded in place. | ||
[[image:Upper_mount_mocked_up_side_view.jpg]] | [[image:Upper_mount_mocked_up_side_view.jpg]] | ||
[[image:Uper_mount_mocked_2.jpg]] | [[image:Uper_mount_mocked_2.jpg]] | ||
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For spindles, I started with the 63 Pontiac spindles as advised in the article. ( Tapered bearings and a good Scarebird kit available.) Unfortunately when I set it on the ground, it was too high. This led to a search for dropped spindles. BOP – they don’t exist. | For spindles, I started with the 63 Pontiac spindles as advised in the article. ( Tapered bearings and a good Scarebird kit available.) Unfortunately when I set it on the ground, it was too high. This led to a search for dropped spindles. BOP – they don’t exist. | ||
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