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Discussion Starter · #1 · (Edited)
Hey guys,

So I am in the process of getting new tires, the ones I have are the ones that came with truck and are 265s. How much performance will I be losing with a bigger tire? Maybe some of you drag guys can give some insight. Ideally I'd love to go with 315s, but if you really lose a lot of speed and power from a heavier tire then I'll step down to a 285. Either way, I'm not going back to 265s. The truck looks like a body builder that never works out legs.

 

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The bigger the tire the harder it is going to be on the drivetrain. Period. I've raced on 35's. It's not bad actually, but i like 33's as a happy medium.
 

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Discussion Starter · #3 ·
The bigger the tire the harder it is going to be on the drivetrain. Period. I've raced on 35's. It's not bad actually, but i like 33's as a happy medium.
Sorry meant 315s not 35s. My bad, I fixed it in the original post.

But you think you lose much on the track? Time wise maybe?
 

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I think I gained a couple tenths stepping down a size. Its been a couple years.
 

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I dont know track times, but i know when i went from a stock 265/70r17 to a 35x12.50r17 mud tire the power loss was ridiculous. I almost didnt even like driving the truck it felt so slow. Put a smarty on and was much better though


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If youve got the power to overcome the extra weight, a slightly taller tire can help on the top end with mph by dropping some rpms. Im talking like a 32 or 33 size, not overkill 37 as an example. With you having EFI, rpm is available and can fuel to it, but is the valvetrain amd motor itself up to the task of turning past 3800 rpms for a few seconds when racing
 

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Discussion Starter · #7 ·
If youve got the power to overcome the extra weight, a slightly taller tire can help on the top end with mph by dropping some rpms. Im talking like a 32 or 33 size, not overkill 37 as an example. With you having EFI, rpm is available and can fuel to it, but is the valvetrain amd motor itself up to the task of turning past 3800 rpms for a few seconds when racing
So would the 285s be a better happy medium for being easier on the drivetrain and motor? What were you running when you did the Diesel Challenge?
 

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I'm on 315's and plan to go to 305's to reduce drive train strain a bit. The power loss isn't the issue for me. With your set up going from a 265 to 315 you will notice it but it won't be insane. A 285/75 will offer the look for filling the wheel well(from side profile) but with the slightly narrower tread patch you won't notice as much of a power loss as 315's even though they would have roughly the same OD.
 

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I run 305/70/17 terra grapplers which is about a 34. It's a little taller than I want but the width is nice. I'd really like something about 32" tall in this width without going to 20s.
 

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Sorry meant 315s not 35s. My bad, I fixed it in the original post.

But you think you lose much on the track? Time wise maybe?
315's are pretty much the same as 35's.
 

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315 is the width. Could have a 27" tall tire 315 mm wide.
Glad someone said it...

If you go up in overall diameter you will loose RPM but gain MPH. On my trucks I have always had a higher MPH and a lower ET with taller tires.

However, there is a happy medium. I find that my 305/50/R20 dont perform as well as my 285/70/17s do but only because of the added weight of the large wheels. If all other variables are kept the same then the rule of thumb will stand true. Taller tires = slower ET higher MPH and smaller tire = faster ET and lower MPH.

The good thing about these trucks and launching in 4wd is that you can get away with baby tires and still get traction up to some pretty good power levels.
 

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I run 305/50-20 Toyo and I don't plan on changing. I'm more into drag racing so I like performance tires instead offroad tires. Sounds to me like that's the direction you are going so I would recommend that size. My mechanic has ran well in the 10s cutting a 1.6 60ft with 305/50-20 tires. I run low 8s in a 1/8mi with my tires and I have 550hp. Basically in the 1/4 I should be running high 12s in a QCSB.
 

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I run 305/70/17 terra grapplers which is about a 34. It's a little taller than I want but the width is nice. I'd really like something about 32" tall in this width without going to 20s.
Those are the 305's I'm considering going to. Got pics? Leveled, reverse leveled or stock stance?

When mentioning I'm pretty sure we can safely assume a 315 is referring to a 70 aspect ratio. If that isn't the case the poster should specify.

315's are pretty much the same as 35's.
Depends on the manufacturer. They can range from 34.6-35" in OD.
 

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Discussion Starter · #15 ·
I run 305/50-20 Toyo and I don't plan on changing. I'm more into drag racing so I like performance tires instead offroad tires. Sounds to me like that's the direction you are going so I would recommend that size. My mechanic has ran well in the 10s cutting a 1.6 60ft with 305/50-20 tires. I run low 8s in a 1/8mi with my tires and I have 550hp. Basically in the 1/4 I should be running high 12s in a QCSB.
305s are basically the same as a 285 except they are a bit wider correct? Not that a 4x4 really needs any more grip on the road.

Very interesting about the taller the tire, the better the mph. I'm sure there is a nifty physics principle behind that lol.
 

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Alright I'm not trying to hijack this thread but my truck has a 6" with 37s. If I dropped the size down to a 4" with 35s would the gain be worth that effort?

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My 35's costed me 3/10ths and 3 mph... Dropped to a 265/70/17 to pick up the 3/10ths and 3mph... The truck definitely felt like it had a much higher load on the motor with 35's though.
 

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Discussion Starter · #18 ·
Alright I'm not trying to hijack this thread but my truck has a 6" with 37s. If I dropped the size down to a 4" with 35s would the gain be worth that effort?

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Judging by how this thread has been going, the combo of lowering the lift and smaller tire will definitely make a difference. There's a reason why guys with big lifts are at a bit of a disadvantage at the track.
 

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305s are basically the same as a 285 except they are a bit wider correct? Not that a 4x4 really needs any more grip on the road.QUOTE]


305 are a bit wider than 285 and you can see the difference. The ones I run are 32" tall and if you want to lower the truck it will look sick. Obviously with a 4x4 you can't lower it much but it looks great with the 32" tires. I have Bilstein 5100 shocks with remote reservoir. Works great for me and everyone else I know who runs them.
 

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I really would love to lower mine but he original owner cut the original mounts off the frame from the new long arm lift. If I could get smaller coils and lower blocks in the rear I'd go for it!

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