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Tires for 79B

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TNMGB

TNMGB

Jedi Trainee
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'Tis the time for new tires for my 79B and I have checked around for 165-70-R14s which is what's on there now. I called NTB and the guy said I could go with a slightly lower profile tire and get 175-65-R14s. Is this an okay size to go with? He said slightly wider and a slightly lower profile wouldn't mess with the speedometer very much if any. Input would be appreciated!
Thanks!
TN MGB
 
Thanks, Jaybird...I'll check that out. It's the 65 part I'm wondering about.
TN
 
23.1" dia for the original
23" dia for the replacement

So if you were going 100mph your speedo would be off .43 of a mph.
 
65 would be ok. 70-series will lower your revs on the freeway at the loss of a little low-speed acceleration.
 
Thanks. Since I've had issues finding replacements for what's on there now, I appreciate any advice I can get. I just wanted to make sure I wasn't doing something stupid by putting a different size tire on there and dealing with whatever the consequences were. By the way, Jaybird, the age of my tires beats yours...my receipt from the PO was from...1987!!! Geez, I can't get into new tires soon enough!
TN
 
Just a footnote TNMGB, in the reference tread I was asking on the forum about 195 65 on 15 inches not 14.

My old tires (which are 18 months) were 185/70/14 and were perfect for the task (on rostyle wheels)
 
FWIW, I just ordered new tires for the GT today, 185/70R14. I went with Sumitomo HTR-200. They appear to be the best performing tire available in that size.

Remember you can always go with a size other than stock and have your speedometer recalibrated. A complete speedo rebuild and calibration will cost around $100 but then you can continue to use your preferred size tire without worry.
 
Thanks, Steve. I guess a lot of what I'm wondering is: what are the pros and cons of going with a wider tire and do I want to really want/need to stick with 70 for the profile size?
TN
 
Biggest concern I might have would be whether they will rub on the fender lip in the rear, esp. drivers side. I have Michelin 185/70 x 14s on Rostyles and they just fit.
 
A wider tire will offer more grip and a smoother ride. The downsides are more road noise, heavier steering and more stress on any old, worn suspension components. There's really no reason to stick to a certain tire profile. Go with the size that suits your driving style. 70-Series is perfectly suited to give a smooth ride. 60-Series is the best performer but will give a rough ride and is best suited to a modified car. 65-Series is a good compromise but may cause higher RPMs than 70-Series and you might need to recaliarate your speedo.
 
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