Max tire size for 1999 GT?

[MathewMM]

Hello all,
This has probably been asked millions of times but I've been unable to find a definitive answer. I'm currently running 275/35r17 on all four corners of my car, as well as a 2" drop for my suspension. and I'm wondering what the max width of the rear tire could be on an 18 inch rim. I'm planning on changing my setup in the spring and wanted to get a headstart for assembling the list.

Thanks in advance!

 

[Roots-type]

An 18 by what? 9? 10? 11?

 

[MathewMM]

An 18 by what? 9? 10? 11?

I'm still learning everything about tires my bad, I was thinking 18x10 or 18x11 but I'm not sure tbh. I've heard of backspacing but not too sure what that is at the moment. I'm trying to create a flush look at the rear with a tire larger than 275 as that's not giving me grip for the mods I have on my car. And I like the aesthetic of large tires.

 

[Roots-type]

I'm still learning everything about tires my bad, I was thinking 18x10 or 18x11 but I'm not sure tbh. I've heard of backspacing but not too sure what that is at the moment. I'm trying to create a flush look at the rear with a tire larger than 275 as that's not giving me grip for the mods I have on my car. And I like the aesthetic of large tires.

What are your mods and what is your budget for wheels and tires? There's several ways to go about this depending on what you want to invest.

An 18x11 will give the closest look to absolutely flush without using spacers. An 18x10 does a good job filling the rear quarter out as well. You'll want to use a 305/35 or 315/30 tire, delete the quad shocks and roll the rear fender lips to keep the sidewalls of your new rear tires free of slash marks. I prefer a 305/35 because it's sidewall is most close to stock, the 315/30 is a tad wider but the sidewalls are too short in my opinion.

Less expensive but still good wheels to choose from would be: SVE, AM, AFS, XXR. Custom forged wheels would be CCW, Weld, True forged, HRE, Iforged. These are just a few of the more typical wheels.

I should note- a 305 should be the widest tire used on an 18x10. It also fits an 18x11 very well.

 

[MathewMM]

What are your mods and what is your budget for wheels and tires? There's several ways to go about this depending on what you want to invest.

An 18x11 will give the closest look to absolutely flush without using spacers. An 18x10 does a good job filling the rear quarter out as well. You'll want to use a 305/35 or 315/30 tire, delete the quad shocks and roll the rear fender lips to keep the sidewalls of your new rear tires free of slash marks. I prefer a 305/35 because it's sidewall is most close to stock, the 315/30 is a tad wider but the sidewalls are too short in my opinion.

Less expensive but still good wheels to choose from would be: SVE, AM, AFS, XXR. Custom forged wheels would be CCW, Weld, True forged, HRE, Iforged. These are just a few of the more typical wheels.

I should note- a 305 should be the widest tire used on an 18x10. It also fits an 18x11 very well.

Thank you!
As for the mods on my car, its pretty much all over the place. I swapped a cammed coyote in it this year so that's why I need the beefier tires, but the suspension is fairly stock. I havent touched the rear end or any suspension. The previous owner dropped it by 2" all around but I'm not sure with what springs or what their method was, I havent paid much attention to it as I planned on putting the car on bags soon anyways.

I've heard of the quad-shock delete but I havent done much research. Would that cause unbearable wheel hop? Keeping in mind my car has never seen a track and most likely never will, theres none within a 5hr radius of me, so all pulls are done on the highway and not a prepped surface. Is the quad-shock delete extensive?

The rims I've had my eyes on are the HRE 301, price isnt a concern for any of these parts as I've got a stable job and all winter to save up for it. 305 sounds meaty enough for me so I'll probably stick with a 18x10, but I'll keep my eyes open. Gotta learn how to roll fenders now as that's new to me as well

 

[jayk17]

If you are aiming for a staggered look, you can run 265/45/18 tire on the front and 295/40/18 tire on the back. Check out Dunlop, Falken tires and Nitto for possible tire options.

 

[Stage 4.6]

On my wifes 99GT i currently have 18x10s with 295-35s with no issues of rubbing. Ive had in the past a Toyo TQ Drag radial 305-40 on it and fit well but the tire was extremely close to the quad shock.