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Old 08-24-2020, 09:30 AM
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racerboy racerboy is offline
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Default 1970 TA shocks with Polyglas tires

If I am planning on running the stock Polyglas bias ply tires, does it make any sense to upgrade to a set of Bilstein shocks? The reason I ask is that I took the car out the other day and it rides kinda rough over bad pavement. I was thinking of upgrading to a better shock but I read somewhere that if you run bias ply tires, you won’t gain much because they are designed to run with radials. I like the stock tires on the JW rims, so if I was going to run radials, I’d have to get another set of wheels. If I can’t run the Bilsteins, what’s the best shock to run with the Polyglas tires?


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Old 08-24-2020, 09:58 AM
NAPA68 NAPA68 is offline
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My 71 has the same set up as you speak of. Having said that, I think it rides and handles alright.

On top of that, I believe the valving of compression to rebound is decidedly different with the original conventional oil shocks. My experience with Corvette's dictates the ride is much better, with a shock that is valved like OE. Outside of buying a set of repo spirals, I do not know where one can buy just an old style oil shock.

I suspect if you comb eBay, you can find some NOS replacement shocks (oil based).

Hope that helps,
Tim

  #3  
Old 08-24-2020, 12:01 PM
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leeklm leeklm is offline
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Back in the 80s when these old cars were my daily drivers, I had a couple that were still running bias ply tires. I would use a run of the mill "Monroe matic" or similar low end gas shock, which seemed to work well on bias or radial tires for a smooth soft ride. Although "soft" may be an overstatement when running bias tires!

Anytime I have moved to a KYB, Bilstien, or other performance shock, the road became more noticeable, which of course is fine if that is what you are looking for, or want something more performance oriented.

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Old 11-28-2020, 08:58 PM
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I finally got around to installing the Bilstiens today, and even with the Polyglas, the car rides 100% better. To be fair, I’m guessing the shocks on it were approaching 10 yr old (but only about 5000 miles). I don’t know if that had anything to do with it, but every time I hit a bump, the whole car seemed to take the hit. The new shocks, while firm, didn’t jar the car and were much smoother over uneven pavement. I took off all the stickers and painted them grey.




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Old 12-03-2020, 11:32 PM
bobzdar bobzdar is offline
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You could make the switch to the coker Firestone radial wide ovals if you want the bias look in a radial. Not the cheapest but best of both worlds.

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