Front Suspension | 356 Speedster, 550 Spyder, Replica, Automotive Community

I recently welded in adjusters to the beam on my tube frame IM and have two questions.

In doing so I noticed that one of the upper swing arms (??) was sticking in the beam. Turned out that the inside bushing was toast so I replaced both sides of the upper tube's roller bearing and bushes with urethane bushes...the 6 inch long jobs. Now after putting it all together again, one of the arms has some play in the bush after just 50 miles. The arm is secure on the torsion bar, I lubed the bushing, torsion bar is secure in the adjuster (I made sure I lined up the existing dimples in the torsion bar with the locking hex bolts) but seems to be about a 1/16 or so out. Any ideas? The movement is like the tie rod end is gone but that's not the case.

Second question...I recall reading in the IM literature that they used one torsion bar in the front beam as a spring and the other as a anti-sway bar. Seems easy and maybe even makes sense...you secure the center on one bar and let the other float keeping it unloaded like an anit-sway bar. Softens the front for the lighter weight of the speedster/raodster and provides an integrated anti-sway bar. Anyway, having read that in the literature I was surprised that my front beam was set up with both lower and upper being used as a spring. Anyone have a different setup of any thoughts?

Thanks..Brian Puskas

9/4/024:00 PM

Original Post

I recently welded in adjusters to the beam on my tube frame IM and have two questions.

In doing so I noticed that one of the upper swing arms (??) was sticking in the beam. Turned out that the inside bushing was toast so I replaced both sides of the upper tube's roller bearing and bushes with urethane bushes...the 6 inch long jobs. Now after putting it all together again, one of the arms has some play in the bush after just 50 miles. The arm is secure on the torsion bar, I lubed the bushing, torsion bar is secure in the adjuster (I made sure I lined up the existing dimples in the torsion bar with the locking hex bolts) but seems to be about a 1/16 or so out. Any ideas? The movement is like the tie rod end is gone but that's not the case.

Second question...I recall reading in the IM literature that they used one torsion bar in the front beam as a spring and the other as a anti-sway bar. Seems easy and maybe even makes sense...you secure the center on one bar and let the other float keeping it unloaded like an anit-sway bar. Softens the front for the lighter weight of the speedster/raodster and provides an integrated anti-sway bar. Anyway, having read that in the literature I was surprised that my front beam was set up with both lower and upper being used as a spring. Anyone have a different setup of any thoughts?

Thanks..Brian Puskas

9/4/024:00 PM

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