My guess from an outsiders perspective. Selling tune-up kits would be hard for a performance website because it would be very hard to compete with everyones local auto zones or advance auto parts. They sell parts cheap because they can buy in such a large quantity for all the stores.
Ford has their recommended times/miles/etc for their tune-ups. I would stick with the Ford scheduled maintenance.
You can also fit a 285 on a 18 X 9 wheel also. I would go large than the 245 on the front. I have a feeling a 245 would look kinda small on a 9" wide wheen.
I would go 275 in the front and a 295 in the rear on the 18x10s or 275s all around if you have 18X9s front and rear.
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