Tire and rim setup for firebird
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Teching In
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Tire and rim setup for firebird I am new to LS1tech and this is my first post. Sorry if I did something wrong or if I am posting this in the wrong place. I drive a stock '95 firebird formula. I am looking to buy new rims. I have the stock 16 x 8 rims on some shitty cheap tires. They still have 95% tread left but very cheap tires. The tires are 245/50/16. I am looking to get torque thrust II's. My plan is to buy (2) 16 x 8 torque thrust rims for the front on the same tires and get (2) 17 x 9.5 rims for the back and buy some new 275/50/17 tires. I would prefer not to get the same brand of tires for the rear, but I also don't want to buy 4 brand new tires. My question is would having some nice tires in the rear (thinking maybe nitto 455 or some good street tires) that are a different brand than the front be bad in any way? Also would having a different size wheels in the back negatively affect anything? Would it be better to get a lower profile tire in the back to balance things out? I just think that a bigger wheel in the back (wider and taller) would look badass. Btw I drive this car frequently, but it's not my daily. I am 16 and just bought this car by myself. I am going to start drag racing very soon, but it isn't a track only car, so I don't know if radials will be the best option. I also do not drive in the rain. If anybody can guide me in the right direction that would be awesome! Thank you. -Christian
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Joined: Dec 2010
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From: Maricopa, AZ
The stock tire size (245/50R16) is 25.6" diameter. The Rear tires you want to put on (275/50R17) are 27.8" in diameter. That is a huge difference. 2.2" larger in the rear than the front. The ABS is very likely to throw the light and stop working (you'll still have brakes, but no ABS).
The larger tires will also slow you down. No matter what gear ratio you have factory optioned, you will notice slower acceleration and worse MPG from the added tire diameter and from the added wheel mass. The tire diameter alone would be like going from 3.23 to 3.00 gears, that's the wrong way. That's a 7.2% loss in RWTQ. If you want taller tires, you need shorter gears.
You can do 275/40R17 (25.66" diameter) and have a good stance, tire clearance won't be an issue, and that is a common tire size so finding them at a decent price for good tires will be easy.
The larger tires will also slow you down. No matter what gear ratio you have factory optioned, you will notice slower acceleration and worse MPG from the added tire diameter and from the added wheel mass. The tire diameter alone would be like going from 3.23 to 3.00 gears, that's the wrong way. That's a 7.2% loss in RWTQ. If you want taller tires, you need shorter gears.
You can do 275/40R17 (25.66" diameter) and have a good stance, tire clearance won't be an issue, and that is a common tire size so finding them at a decent price for good tires will be easy.
