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what tyres are you fitting to your Manta?

do you know what was original?
Original on all North American spec Mantas was 165R13 on 5” wide steel rims (1971-1974) and on 5.5” steel rims in 1975.

In Europe the GT/E could be had with 185/70R 13 on original 5.5” steel rims, or optional 6” alloy rims.
 

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Opel Rallier since 1977
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I have bought some Pirelli CN36's size 185/70R13 on my 1900. Considering that I ran much larger rally tires for years on a Manta rally car and then a 1900 rally car, I don't expect any issues whatsoever.
 

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Discussion Starter #4
the CN36 is currently the best tyre for cars of that period except possibly the Michelin XDX.

i wondered what brand and tread they fitted originally

Manta Rallier - have you got some pictures of your car on CN36. i bet they look great
 

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Not yet, Nasher..... painting up some wheels first. They are the 'spoke' type wheels from the Manta and SportWagon, so the painting of the silver area on the outside is taking me a while.
 

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the CN36 is currently the best tyre for cars of that period except possibly the Michelin XDX.

i wondered what brand and tread they fitted originally

Manta Rallier - have you got some pictures of your car on CN36. i bet they look great
My 73 Manta came with 165R13 bias-ply tires. I had them put 185/70-13 Michelin X radials. I can't remember the brand. So Opels didn't come with good tires.
 

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My 73 Manta came with 165R13 bias-ply tires.

I see what you did there!

If they were 165R13 then they would be radials. 165B13 would be a bias ply!

FWIW, most of the original spare tires I’ve pulled from Mantas and Asconas have been Goodyear Polyglass tires, 165-13. Bias ply.

Though the later cars often had radials fitted (dealer option, same size).
 

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I have several original tires from two different '75 Opels (Manta and 1900). They used Goodyear G800+S steel belted radials in 165SR13 size. Here are some photos of one. Note the Opel branded tire weight!
 

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I have several original tires from two different '75 Opels (Manta and 1900). They used Goodyear G800+S steel belted radials in 165SR13 size. Here are some photos of one. Note the Opel branded tire weight!
Bill, having stripped hundreds of Opels over the years, I’ve definitely noticed that OEM tire choice seemed to be a regional thing.

Cars originally sold in New England tended to have one type, cars from the south another. The few west coast cars I’ve seen yet another.

Must’ve been a corporate GM decision.
 

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RunOpel
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Wow that tire is in really good shape and what a neat piece of history about the tire weight.
 

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I posted this on your other thread on Kadet OE tires...

I recall from my days as a make-ready mechanic in a Buick dealership that no one manufacturer was standard. We had customers that either had a preference for one brand or another, or a bias against the brand that was on the car, and requested the tires be changed. That would send us out into the lot looking for a car with the sought-after tires and we would switch the tires (occasionally forgetting to swap the spare). This of course is illegal in today's world. This happened more often with the Buicks, but we would occasionally see it with an Opel.

As Rally Bob noted, there were various brands but I am not sure it was strictly a regional thing. For sure, GM and the other manufacturers used multiple tire suppliers so as not to be dependent on any one supplier (especially important in the event that a supplier might be affected by a labor strike).
 

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I see what you did there!

If they were 165R13 then they would be radials. 165B13 would be a bias ply!

FWIW, most of the original spare tires I’ve pulled from Mantas and Asconas have been Goodyear Polyglass tires, 165-13. Bias ply.

Though the later cars often had radials fitted (dealer option, same size).
165 13 bias ply tires must be an American specialty, because over here bias ply tire widths were always expressed in inches.
 

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165 13 bias ply tires must be an American specialty, because over here bias ply tire widths were always expressed in inches.
To add confusion to that...in America various tires were expressed in inches, in P-metric, or in letter sizes.

So you could have, for example, 6.4-13, or 165-13, or even A78-13.
 

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To add confusion to that...in America various tires were expressed in inches, in P-metric, or in letter sizes.

So you could have, for example, 6.4-13, or 165-13, or even A78-13.
Ahhh! Then they came out with the 60-series tires (Height = 60% of width). I replaced the original 165HR-13 tires on my 1970 GT with Goodyear A60-13 polyglass tires that looked really neat, just like real racing tires and with raised white lettering (okay, so I was young...). This alone made the car impossible to handle, especially in wet weather -- the front end just plowed ahead forever.

I was not the only one that made this mistake. Just about every Corvette driver that I knew immediately switched to the 60-series tire and within hours they were all driving around with shredded front fenders: the tires were too wide (or the wheel wells too narrow) so that whenever the car made a turn the tires rubbed the edge of the fender at the top.
 

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I also ran into this. I have no doubt various tire brands were used, but while optional in '74, I believe by '75 they were supplying steel belted radials on the new 5.5" wheels as standard equipment.
 

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I have in my possession the dealer advertising brochures for the 1972, '73 and '74 Opel line. The '72 brochure shows every model except the GT with whitewall tires that appear to be bias-ply, and states the whitewall to be available for all models. The GT shown is clearly wearing radial tires as I remember came standard, both from my days in the Buick dealership and the GT I purchased new in 1970. The '73 brochure shows the Manta Luxus, the GT and the Rallye with blackwall tires that appear to be radial, while the cheaper models are all shown with whitewalls that appear to be bias-ply, while there is no indication at all in the brochure as to the standard tire or options, and there is no indication as to tire size. The 1974 document tells us that bias-ply tires, 165x13, are standard, but that, as of January 1, 1974, steel belted radials would be an available option for all models.

I purchased new in 1973, a Manta Luxus in Blue Max trim, but I forget which tires came on it. All I remember is the fight that I had with the dealer in White Plains, NY over its failure to replace the already-faded seat trim on the back seat, and the trashy quality of the dealer-installed radio. That battle went all of the way to Buick's HQ in Michigan before six separate items were corrected more than three months later.
 

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I found this as the spare in my 74 Manta. I would guess this is one of the original tires that got moved to the spare when the radials got mounted. Looks like a bias-ply to me.
Kind of looks like a radial to me with the way the tread wraps around the shoulders. Does it say bias ply or radial on it anywhere?
 

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I stand corrected. It's a 165-13 or 6.45-13. The tread looks like a bias-ply. You roll off that tread and good luck. It could have 17K on it. That would make it 45 years old. It doesn't look bad. I know my 73 had bias-ply tires when I picked it out on the lot and had them the radials put on before delivery.
 

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