Wheels and tires, tires and wheels?, Need brainpower of the collective Options

[Big Len]

Gentlemen;

I am posting this at the risk of seeming like a lazy ass, but I assure you I have tried to search many other sites and threads within 914World including tech articles. There must be threads on the subject, I just can't find them. I'm still not sure, so here goes.

I have a stock '74 with steelies and want to expand my wheel choices. The car will not be a daily driver nor an autocrosser, just for weekends. After looking at members pictures and PMing a few, I like the look of a black center (5 spoke Fuchs or BBS type mesh with a polished lip). I just received a 5 lug conversion kit from PMB.

I would rather not roll or widen any bodywork for originality's sake, but if I have to, I will. I also read that factory tolerances may vary. I also know, after using the wheel calculator, I'd like to keep the speedometer mostly accurate. (I know wheels aren't original, but a simple bolt on).

So the questions;

What are Fuchs hearts?

Fuchs are "deep" or "flat." Guessing that's the offset.

15 or 16 inch? There seems to be more tire choices for 16, but how will that effect ride/handling?

Offset seems to be the key here. What should I be avoiding?

Thank you in advance for your help.

Len

[r_towle]

so,
backspacing is easier to measure.
This is the distance from the inside lip of the wheel to the inner surface that gets bolted to the rotor.

This measurement cannot exceed 4 5/8 inches or you will rub on the inside of the trunk with the rubber.

Going from there, you can add spacers to decrease that inner number.
Cant make the number larger without removing material from the wheel.
Its a fixed number, cant move the inside wall.

You can move the outside fender by bending it, stretching it, rolling the fender lip, flares etc.

The inside one is the important one.
Offset is the difference (positive or negative) between the backspacing and the true centerline of the wheel.

I use backspacing (do that math to get backspacing) because that is what matters.

For a stock car, you can get 6.5 inch wide wheels, and in some cases 7 inch wide wheels on the car.

The best way to know what you are dealing with (your car is different then ALL other cars) is put on all your 5 lug hardware, then use a straight edge to measure from the rotor mounting surface to any and all parts of the inside of the trunk face....
Also measure to the inside of the fender lip.

Then you know those two numbers and the rest is math.

Rich