Auto 5.0 3.15 Gear Rear Tire Size

[JLear]

I recently picked up a 2014 auto GT with a 3.15 gear and was wanting some advice on rear tire size for the track. I currently have some 28" et streets but I didn't know if that would be too tall of a tire for stockish power. Would a 26" rear get better et's than a 28" or is there no difference at all? Not really looking to waste the money on 26's if they're not beneficial. I know there has been many of y'all that have already been down this road so I figured I would ask for experiences/results. Any input is appreciated!

 

[Grabber Blue 5.0]

What are your other plans for the car as far as mods go?

 

[Unreal]

If you are keeping it bone stock besides tires, 26s may be a better choice. If you are going to start modding then just keep the 28s and add some power.

 

[JLear]

The car won't stay stock long, just thought about going with a 26 if they helped with the et. I'd much rather change a tire than the gears.

 

[2011/5.0]

Tune and stall and you will grow into the 28 it will seem slow out if hole now i would guess 2.0 2.1 60ft add a 4c or 5c circle d 1.55-1.65 60ft range if da around 1200

 

[psfracer]

I knew a guy that had a KB on his auto coyote and there was no change in ET going from 3.15s to 3.73s. That being said, it really does depend on how much rwhp you have and the weight of the car. But with the steep first gear of the 6R80, the general consensus for coyotes with a power adder is the 3.15s are fine.

Now if you plan on staying N/A, then gearing/tire height becomes way more important and much more debatable as far as what is best.

 

[JLear]

Since I already have 28's I will try it on those first, unfortunately I won't be able to do a real world comparison between the two sizes. I tried to find some cheap 26's locally but had no luck at all.

 

[Unreal]

I've ran both and like the 28 better. Also ran stock gear, 3.73s and 3.31. 3.31 and 28" seems to be the way to go for a fast bolt on coyote. Running a 3.31 26" combo now until I wear them out then going back to a 28".

 

[rcm90]

Since I already have 28's I will try it on those first, unfortunately I won't be able to do a real world comparison between the two sizes. I tried to find some cheap 26's locally but had no luck at all.

I can probably get you a set of used 26" tires if your willing to drive to Cincy.

 

[JLear]

I've ran both and like the 28 better. Also ran stock gear, 3.73s and 3.31. 3.31 and 28" seems to be the way to go for a fast bolt on coyote. Running a 3.31 26" combo now until I wear them out then going back to a 28".

I searched locally for some 26's with no luck, plan on going to the track on Saturday with the 28's if the weather cooperates.

I can probably get you a set of used 26" tires if your willing to drive to Cincy.

It would have to be a pretty good deal to make the drive, just guessing I'd say it's 2 hours one way lol.

 

[Five Oh Brian]

I've run 28" M&H D/R's in my '14 GT 6R80 successfully from near stock (with the factory 3.15's) all the way through its current mods...

• With just a tune & the D/R's, went a best of 12.60 @ 111+.
• Added a converter & 1-pc driveshaft and went a best of 12.03 @ 113+.
• Added 4.10's and went a best of 11.93 @ 116+.
• Added an O/R H-pipe and went a best of 11.80 @ 117+.

In my opinion, the 28" D/R is the way to go in the cars. I've run a 26" but 1) they look odd/undersized, and 2) the 28" allows for a taller sidewall which tends to hook better and unload the suspension less.

 

[psfracer]

In my opinion, the 28" D/R is the way to go in the cars. I've run a 26" but 1) they look odd/undersized, and 2) the 28" allows for a taller sidewall which tends to hook better and unload the suspension less.

And, the taller the tire the larger the contact patch. As long as the car is geared right, the taller tire should not be a problem. You have great results for a n/a car on a 28. That steep first gear helps I am sure.

 

[JLear]

Myself and a buddy drove almost 1.5 hours on our way to the track when we got a call that it was raining and they had cancelled, so no times for me this weekend.