Suspension question and soliticing opionions on body accesso

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Steve Raucher
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Suspension question and soliticing opionions on body accesso

#1 Post by Steve Raucher »

So our '58 Speedster has new shocks all around. Lately I have been hearing an occasional "knocking" sound when car is driven over bumps etc. I know the left rear sits about 1" lower then the right rear. Maybe it is a torsion bar adjustment?
But this knocking sound is bugging me. Maybe it is the rubber bushings at the trailing arms? Any input or suggestions is appreciated. Back in the day the metal brackets attached to the car that the rubber bumpers bang up against on top of the rear shocks were removed and are gone. Car has a lowered stance likely because of this etc.I did not have this knocking sound in the past even with the old worn out shocks. GRRRRRRRR!
Now for opinions on what color to paint this fiberglass tonneau. I think dark blue like the rest of the car and silver at the raised bubble being the helmet pad. Others say do it Silver with the bubble done dark blue. Opinions?
Cheers,
Steve
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Geoff Fleming
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Re: Suspension question and soliticing opionions on body acc

#2 Post by Geoff Fleming »

Since the noise appeared after the new shocks were installed it is most probably one of the rear shock absorbers needing more tightening of the top bolt or thicker rubber spacers at the upper mount point.

Ivan Fuller
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Re: Suspension question and soliticing opionions on body acc

#3 Post by Ivan Fuller »

Top bolt of the rear is probably too long and taps the body on bumps. Same as Geoff is saying but you may need to shorten the bolt. Had the same problem on my car.
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George Walling
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Re: Suspension question and soliticing opionions on body acc

#4 Post by George Walling »

Steve I can't help you on the front-end knocking sound but here is a thought on the tonneau bubble. Take a picture of the car with a digital camera then on your computer change the colors on the picture. I would think that silver with maybe some pin stripping would look really nice but I'm not sure how the 356 world would except pin stripping on a Speedster. I have the wife change color combinations when I'm questioning a color for a car so it might help you. On a side note will you be attending the WCH in August ? The wife and I will have Eleanor at the holiday so hope to see you and your Speedster. Hope this helps.
George E Walling

Norm Miller
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Re: Suspension question and soliticing opionions on body acc

#5 Post by Norm Miller »

Originally Porsche used larger & thicker rubber bushings than today's shocks are equipped with, so two bushings on the lower side should cure the knocking.

Norm
 

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Emil Wojcik
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Re: Suspension question and soliticing opionions on body acc

#6 Post by Emil Wojcik »

I'd paint the tonneau all body color. I personally just don't see the need to draw too much attention to it by adding a second color. It will stand out enough just by being there and will look more period correct.

I made a similar tonneau for my MGB and chose to keep it all body color for that reason (haven't had the upholstered headrest made yet):
Image

If you really want to add the second color, paint the bubble so you draw the attention to it, rather than to the main body of the tonneau.
Emil Wojcik
'64 356C Euro coupe
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Larry Coreth
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Re: Suspension question and soliticing opionions on body acc

#7 Post by Larry Coreth »

Steve,
Just to be clear, were the suspension stops (where the rubber bumpers impact at full jounce) cut off at the front or rear ? If the rear then the axle tubes would hit the rear sub-frame when you hit that large pot hole ! This would be a serious clunk. Also the shocks could be bottoming out internally. Now if your old shocks had rubber bumpers inside the upper tube, this may have allowed a soft landing, i.e. no clunk. Most of the I shocks I have used, Boge, Koni, do not have such a rubber bumper since it would normally be redundant with the stock suspension stops.
BTW just removing the suspension stops would not lower the car only a torsion adjustment will accomplish this. Now if these stops were removed because the torsion bars had been adjusted to give a lower ride height such that the rubber bumpers were sitting on the stops all the time, this I would say is some radical surgery ! It would have been easier to cut the rubber bumpers down some. Also if one side is an1” lower than the other side, you would be wise to fix this to get both sides reasonably equal, within ¼”.
Larry Coreth
Roanoake Rapids, NC

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