About to order rims & tires, want to double-check.

[PT Goat]

Just for reference, here's the car with its current 215/65/15s (26") and I think they look tall enough. And I'd be going an inch higher with the 255/45/18.

Edit: Damn, pics won't fit. Will resize and try again tomorrow.

[LCAC_Man]

Originally Posted by PT Goat

Just for reference, here's the car with its current 215/65/15s (26") and I think they look tall enough. And I'd be going an inch higher with the 255/45/18.

Edit: Damn, pics won't fit. Will resize and try again tomorrow.

Yeah, but you're doing it at the expense of about 25mm of sidewall:
255/45=114.75mm sidewall
215/65=139.75mm sidewall
Thats really going to be a huge contrast, additionally your front tire while smaller in diameter, will have more sidewall, and likely look out of scale
235/50=117.5mm
If you can make the 275/45 work you'll have 123.75mm sidewall which will scale well with your front and give you the height you want.
Those wheel wells aren't anything a six pack and a bad attitude can't take care of
My numbers above are just the straight math, every tire mfr varies a bit so take it for what it's worth (some tell me not much...)

[PT Goat]

I'll do some math and measuring on the 275s.

But as long as I am running a larger wheel in the rear, I'm going to be looking at less sidewall, right? Unless I make it up in tire height, which probably means going wider to stay with the tire I want (F1 GS-D3).

No wonder it's taken me so long to order.

How about a 225/50/17 (25.9" tall) front and the 255/45/18 (27.1" tall) rear? That would be a 4.4" front sidewall and a 4.5" rear. Sound better?

[LCAC_Man]

Originally Posted by PT Goat

No wonder it's taken me so long to order.

How about a 225/50/17 (25.9" tall) front and the 255/45/18 (27.1" tall) rear? That would be a 4.4" front sidewall and a 4.5" rear. Sound better?

Finding tire sizes that work for you, and a tire mfr/model that cover both front and rear sizes is truely a PITA.
The sizes you mention above would work well together, same size sidewall and slightly larger diameter rear. A-Bodies are deceivingly large cars, 27" rear is as small as I would go. My last car was a Buick GS400, I ran a 28"+ 275/55/17 tire on the rear (after installing a smaller tire and not liking it) and it was perfect.
In the end you may have to go to a shop and have a couple different sizes installed and see just what makes you happy.

[PT Goat]

Thanks again for the advice. I am going to order custom redlines, so unfortunately, I'm not going to be able to do any trial fitting first.

Right now I'm leaning towards the 225/50/17 and 255/45/18 in the GY F1 GS-D3. I will search for a taller rear tire, but I haven't found any matches yet in a performance tire, at least not with GY or BFG.

[LCAC_Man]

Not trying to push you one way or the other but an option to get you to taller tires would be:
225/55/17 front
255/55/18 rear
Nice rake, period look in sidewall height, would really fill the wheel wells.