Jeff,
I'm sure that you can guess that my opinion on a beautiful original 73-74 2L like yours will be to keep it stock & period correct.
Another reason to keep with the stock-ish sizes that nobody is mentioning here, is "Ghost Mileage" - wherein the odometer error of +/-10% will significantly devalue an original 2L like yours over time driving it, & showing more mileage than actual.
Member Todd on here who has restored several low original mile 73-74 2L learned that lesson the hard way, when he lost some sale price upon his refurbishment/clean-up of the Bahia Red 73 2L IIRC due to the 195/65HR15s that he used on it for a time driving it.
185/70R15 or 185/75R15 are the closest diameter to the OE 165HR15 (165/80R15) size that were original 73-76 2Ls, & so only have a tiny error.
Use this tire size calculator to see the errors for various sizes yourself:
https://www.tacomaworld.com/tirecalc?tires=...80r15-195-65r15Despite the seeming flood of big tire boyz on here who think that 914 tires have to be big, low profile, fatties with modern treads - it is NOT the only nor best way to go for just new tires. Also, the current repops of Michelins, Pirellis, etc. are made with the modern rubber compounds anyway, and the classic tire tread patterns are in fact pretty effective on our older & lighter cars.
You'll actually get more "Loos" with a truly stock & period correct 914, from what I've seen at the 100+ PCA Concours & other car shows at which I've judged over the past decade, as well as around town. It's a historical & vintage/classic car thing.
There are also the Vredestien 185/70HR15 tires as an option at half the price of the Pirelli & XWX options:
http://www.lucasclassictires.com/185-70R15_c78.htm But even with the most expensive Michelin XWXs on 5 wheels, I'm pretty sure that will be far more cost effective than the 5-lug parts, wheels & tires - & the 185/70VR15 is infinitesimally less tread on pavement than the 195/65R15 options.
There are also several OE size 165R15 (/80 in HR or VR) options if you want pure stock, & don't want to lose mpg with the wider 185s:
http://www.lucasclassictires.com/165R15_c70.htmCoker & Universal tire stores also have classic/vintage tire options, but Lucas Tire is local to me in Long Beach CA, & they can get any tire from their UK affillieate Longstone Tyre - so I'm showing you them>
https://www.longstonetyres.co.uk/tyres/165x15.htmlhttps://www.longstonetyres.co.uk/tyres/185x15.html If you're looking for better performance, then go to 185/70R15 - if not but want the OE look & size of 165R15 (165/80R15) - all in the H, T or V speed ratings.
Sometimes it's just best & nicer looking to have & show-off a classic car as it was back in the day, without all of the resto-mod & hot-rodding tricks of today!
I'm sure that your avatar buddy Steve would agree!
You may also want to contact the guy with the Leistritz muffler question post in the Garage Forums.
Cheers!
Tom
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