15" Tire sizes- Will these fit

[Ace23]

I have #1867 car. I want to go to 15" wheels and tires and I am looking at Nitto NT555R to run on all 4 corners for a street car. Will there be any fitment issues based on the below dimensions? I have come across older threads where 325-50-15 have been used but the tires were MT ET's that have now been discontinued. Thank you in advance


Front

P275/60R15 overall diameter 27.76, overall width 11.10, wheel size 7.5-(8.0)-9.5

Rear

325/50R15 overall diameter 27.99, overall width 13.11, wheel size 9.0-(10.0)-11.5

[CHRIS DAMSCH]

I ran the 325/50/15 bf Goodrich drag radials for a few years. They fit. Barely

[DWRAT]

That's a crazy big front tire.
You may want to double check the posting size.

[Shootnride]

The 275/60R15's are too big for the front. That is the size that SPF puts on the rear as standard equipment. I have 255/60R15's on the front of mine and I certainly wouldn't go any larger. Also, I suspect you will have rubbing issues with that size rear tire. I use to have the MT 12-28x15 SR's on the rear of mine and although I was able to run them, I couldn't get the rear ride height down to where I wanted it without rubbing issues. I now run the MT 295/55R15 ST's and they work fine.

Ted

[CHRIS DAMSCH]

I believe somebody ran 275/50/15 on the front. Can't remember who. It was a drag radial on all 4 corners thread years back

[Ace23]

Originally Posted by DWRAT

That's a crazy big front tire.
You may want to double check the posting size.

I've got 275/45/17 on the front and 315/35/17 on the rear

[Ace23]

Originally Posted by Shootnride

The 275/60R15's are too big for the front. That is the size that SPF puts on the rear as standard equipment. I have 255/60R15's on the front of mine and I certainly wouldn't go any larger. Also, I suspect you will have rubbing issues with that size rear tire. I use to have the MT 12-28x15 SR's on the rear of mine and although I was able to run them, I couldn't get the rear ride height down to where I wanted it without rubbing issues. I now run the MT 295/55R15 ST's and they work fine.

Ted

I admit I haven't studied up I tire sizes so I assumed a 275/60/15 would fit because my current tire is a 275/45/17. I may need to revaluate what I plan to put on the front. Was really trying to stay away from mixing tire brands and tread patterns. Nitto does offer a 275/50/15

[Andrewyoung78]

ace, I'm running nitto555r all four corners and loving it. 275/50/15 front with 11" footprint and 325/50/15 13.11" footprint. No clearance issue at all while I adjusted the coilover. I had 255/60 F and 275/60 R MT drag street. Although in hawaii doesn't rain much but its also ok in the rain.

[Ace23]

Originally Posted by Andrewyoung78

ace, I'm running nitto555r all four corners and loving it. 275/50/15 front with 11" footprint and 325/50/15 13.11" footprint. No clearance issue at all while I adjusted the coilover. I had 255/60 F and 275/60 R MT drag street. Although in hawaii doesn't rain much but its also ok in the rain.

Very interesting.....thanks for your input. The motor is ready to go in and we plan to put some breakin miles on the car with all the changes that we did. When we are confident everything is the way we want it I am going to dive off and do the tires and rear gear. What rear gear ratio are you running? We did a T-56 swap on my car and going to the taller tires I am going to need more gear than my current 3:31.

I am interested in your take on running the 275-50-15's in the front. What type of driving do you typically do? Is it as heavy feeling in the steering as people have said it would be? My car is a 100% street car that I do not drive in the rain nor track. We don't really have any crazy backroads around here so it doesn't see any hardcore spirited driving other than lots of 100mph sprints and rollons. It is purely a cruiser that I like beat on occasionally.

[Shootnride]

Originally Posted by Ace23

We did a T-56 swap on my car and going to the taller tires I am going to need more gear than my current 3:31

You really need to take into consideration the gear ratios in your transmission when making a decision on your rear drive gearing. First gear is especially important. I have a 3.27 first gear and am running 3.73 rear end gears. This combination makes first gear borderline useless. I wish I had your 3.31 rear end gears.

Also, when you're making a decision on tire sizes, make sure that the sizes that you choose will allow you to set the car at the ride height you want without creating any rubbing issues. I personally made an error in judgement with my first tire size selection and it was a little costly to remedy that mistake.

Just some food for thought.

Ted

[xb-60]

Have you used Superformance's Second Strike Gearing Calculator? If not, well worth a look for simulating different gearing setups.

Cheers
Glen

[Andrewyoung78]

Ace, my new 275/50 setup is lightly on the steering then the 255/60. Its a cruiser and occasional back road driving. I finally achieved the looks that I really like on the superformance cobra. Of course this setup is not for autocross or road racing buy suit my driving style thats all matter.

[66gtk]

Originally Posted by Andrewyoung78

Ace, my new 275/50 setup is lightly on the steering then the 255/60. Its a cruiser and occasional back road driving. I finally achieved the looks that I really like on the superformance cobra. Of course this setup is not for autocross or road racing buy suit my driving style thats all matter.

Can you share some photos, please?

[Andrewyoung78]

Sorry still learning how to post photos

[Ace23]

Originally Posted by Shootnride

You really need to take into consideration the gear ratios in your transmission when making a decision on your rear drive gearing. First gear is especially important. I have a 3.27 first gear and am running 3.73 rear end gears. This combination makes first gear borderline useless. I wish I had your 3.31 rear end gears.

Also, when you're making a decision on tire sizes, make sure that the sizes that you choose will allow you to set the car at the ride height you want without creating any rubbing issues. I personally made an error in judgement with my first tire size selection and it was a little costly to remedy that mistake.

Just some food for thought.

Ted

Ted
Thanks for the insight. I have exhausted second strike gearing calculator and while I recognize it is only a simulator I don't think the 3:31's are going to be enough gear. The current setup is running a 315-35-17 so when I go to a 325-50-15 that takes quite a bit of gear away. I figured with the 6 speed and the tire swap the gearing is going to need attention. The 3:31's were okay on the street but I always wanted a bit more gear but never had the tires to support it.

Originally Posted by xb-60

Have you used Superformance's Second Strike Gearing Calculator? If not, well worth a look for simulating different gearing setups.

Cheers
Glen

Glen,
I have run this a thousand times. Based on going up in tire size the following occurs.....if I ran a 3:90 rear gear it would be like my existing setup as if it had a 3:73.....if I ran a 4:30 rear gear it would be like my existing setup as if it had a 4:10. Going from the TKO-600 .84 to the T56 with 2.66 first gear I am thinking the rear gear isn't worth doing unless you were changing the actual gear from a 3:31 to a minimum of a 3:90 or higher. I would think the sweet spot for my driving style with drag radials will be a ratio between 3:73 and 4:10.

Originally Posted by Andrewyoung78

Ace, my new 275/50 setup is lightly on the steering then the 255/60. Its a cruiser and occasional back road driving. I finally achieved the looks that I really like on the superformance cobra. Of course this setup is not for autocross or road racing buy suit my driving style thats all matter.

Thats great to hear you are happy with it considering so many people say it can't or shouldn't be done. Would love to see some pictures of the setup. I can PM my phone number if you want to text them.