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Who switched from 305/45r17's to 315/50r17's??

Markp

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#21
Would the 315s be too much for a stock Redeye with 2.62s? My best 60 on the 305s so far is 1.474. I am hoping I can get into the low 1.4s
 

motorhead

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#22
Would the 315s be too much for a stock Redeye with 2.62s? My best 60 on the 305s so far is 1.474. I am hoping I can get into the low 1.4s
The additional rotational mass is a greater concern than the gearing since first gear is so low already. I'd also look at what engine speed you are trapping at with the current tires - are you going to benefit from the increased diameter of the tires throughout the entire run or will it potentially slow you down by using them? You can easily log your acceleration rate in HP Tuners to see if there is/was a trade off.
 

WhipCat

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#23
I swapped over. Helped a little bit. Still can’t get my 60’ to drop under 1.45

I keep blowing the tires on the hit. I got to try taking power out of it on launch.

5F94A242-5BF0-484F-A6D7-C9C19AF626DC.jpeg
 

DRAGRCR

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#24
Would the 315s be too much for a stock Redeye with 2.62s? My best 60 on the 305s so far is 1.474. I am hoping I can get into the low 1.4s
If you can get the car to hook it will be faster on the lighter and shorter tire. On a stock car the next thing I would do is the 3.09's and/or weight reduction. At that point I might pair the 315's with the 3.09's but the car would still be faster with the shorter/lighter tire if you have really good prep and it will hook. Almost always the smaller/shorter tire is lighter. Only exception that I can think of is some Drag Slicks are made in a light weight version. In that case they might be faster even though they are taller. If you are going to modify with big power I would stay with the 2.62 gear.
 

TNREDEYE

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#25
Would the 315s be too much for a stock Redeye with 2.62s? My best 60 on the 305s so far is 1.474. I am hoping I can get into the low 1.4s
I have never run the 305 tire but I have run the 315 w a 2.62 as well as a 3.09 gear.
I had a best of 1.48 w the 2.62 gear and so far I've been 1.46 w the 3.09.
Different tracks but similar DA of 600'.

This doesn't directly answer your question but it's at least some real world info for you.

Also, it appears that their is a difference of around 7 lbs ea between the 305 vs 315 tire. Obviously 14 lbs of rotational mass is theoretically worth some et.
 

Hpindy

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#26
Would the 315s be too much for a stock Redeye with 2.62s? My best 60 on the 305s so far is 1.474. I am hoping I can get into the low 1.4s
For what it's worth here is my opinion.

On a stock power 2.62 car I would stay with the 305's .

Plus on a regular body you will need to "massage" the rib in the inner fender .

Sent from my BBF100-2 using Tapatalk
 

hellno

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#27
I have the 315 with the 2.62 and I cut a 1.39 best and a1.40 before it
 

Hpindy

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#28
I have the 315 with the 2.62 and I cut a 1.39 best and a1.40 before it
With the added power you new need more tire to hook up . But it would be curious to see what a 3.09 gear would do VS the 2.62 in your car . You will have to test that next summer .

Sent from my BBF100-2 using Tapatalk
 

hellno

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#29
With the added power you new need more tire to hook up . But it would be curious to see what a 3.09 gear would do VS the 2.62 in your car . You will have to test that next summer .

Sent from my BBF100-2 using Tapatalk
I have the 3.09 but it’s noises my next project will be taking it apart and seeing if I can find the pinion bearings for it my gears look good in it and I’m hoping I can find a source on parts other then the gears which I believe aren’t available
 

Marc W

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#30
I swapped over. Helped a little bit. Still can’t get my 60’ to drop under 1.45

I keep blowing the tires on the hit. I got to try taking power out of it on launch.

View attachment 7750
I can actually see the negative camber you've got in the rear in that picture. Go positive and you'll do better.
Nice picture btw.... Looking forward to GB!
 

WhipCat

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#31
I can actually see the negative camber you've got in the rear in that picture. Go positive and you'll do better.
Nice picture btw.... Looking forward to GB!
Yep. We will be getting an alignment done for the this wheel and tire combo next week.
Appreciate the heads up.
 


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