Direct comparison 26" vs 28" tall tires

[poncho@home]

Has anyone with basically stock power levels, 3.31 gears with a MT-82 ever try both 26" and 28" tall drag radials or bias-ply and see what the impact of the tire size is?

Personally I think the 26" will be better for the gearing, but could the 28" extra side wall help on launch and negate the gearing disadvantage?

I ask because only M&H seem to make a 26" bias-ply tire now so choice is limited to that tire or the more choices with 28" tires.

Sponsored

 

[poncho@home]

I am doing some simulations on this website:

https://www.blocklayer.com/rpm-geareng.aspx

I am thinking maybe a 3.55 rear gear swap with a 28" tall might be a good choice.

 

[LETHAL]

Has anyone with basically stock power levels, 3.31 gears with a MT-82 ever try both 26" and 28" tall drag radials or bias-ply and see what the impact of the tire size is?

Personally I think the 26" will be better for the gearing, but could the 28" extra side wall help on launch and negate the gearing disadvantage?

I ask because only M&H seem to make a 26" bias-ply tire now so choice is limited to that tire or the more choices with 28" tires.

Yes and yes... to the bold.

I have a set of Hoosier D06 28X10-17 Slicks. On the street (few test hits) the car feels like a turd honestly. OEM 19's and It is a rocket. 3.55 gears here too.

 

[Grimace427]

Has anyone with basically stock power levels, 3.31 gears with a MT-82 ever try both 26" and 28" tall drag radials or bias-ply and see what the impact of the tire size is?

Depends on your power level and trap speed plus your engine RPM when crossing the line. You want to end near peak powerband so match the tire size with your gear.

Yes and yes... to the bold.

I have a set of Hoosier D06 28X10-17 Slicks. On the street (few test hits) the car feels like a turd honestly. OEM 19's and It is a rocket. 3.55 gears here too.

Not exactly scientific. Bias-ply slicks are much softer than street tires and have greater rolling resistance.

 

[poncho@home]

Depends on your power level and trap speed plus your engine RPM when crossing the line. You want to end near peak powerband so match the tire size with your gear.


Not exactly scientific. Bias-ply slicks are much softer than street tires and have greater rolling resistance.

I am talking about near stock power levels, I have a PP1 tune only.

I agree that you want to be near or at peak power crossing the line, that's why I went with the shorter drag radials, but I think I want to go to bias-ply since I have a manual car.

 

[Grimace427]

I am talking about near stock power levels, I have a PP1 tune only.

I agree that you want to be near or at peak power crossing the line, that's why I went with the shorter drag radials, but I think I want to go to bias-ply since I have a manual car.

Crossing the line in 4th gear with 3.31 gears you'd want the 26" tires. With 3.55 gears I'd pick the 28" tires since it would give me room to increase power and trap speed. With 3.73 gears the 28" tires are practically mandatory to prevent hitting the rev limiter.

 

[LETHAL]

What about crossing the line in 7th at 7800? LOL

 

[poncho@home]

What about crossing the line in 7th at 7800? LOL

Haha! Those 10 speed autos really change our thinking

 

[brucelinc]

http://www.wallaceracing.com/gear-speed.php

With a 28 inch tall tire, you would be at 6000 rpm at 115 MPH in 4th gear. With a 26 inch tire, you would be at 6500 rpm at 115 MPH in 4th gear. Your car would be nearer the power peak with the shorter tire. Add to that the fact that the smaller tire is slightly lighter in weight so there is less rotational mass. The 28 inch tire would give you the equivalent of a 3.22 axle ratio. The 26 inch tire would give you the equivalent of 3.49.

I have no first hand experience trying both sizes. However, I have seen plenty of guys at the strip wondering why their cars got slower when they put on too tall tires for their gear ratio and engine output.

 

[poncho@home]

http://www.wallaceracing.com/gear-speed.php

With a 28 inch tall tire, you would be at 6000 rpm at 115 MPH in 4th gear. With a 26 inch tire, you would be at 6500 rpm at 115 MPH in 4th gear. Your car would be nearer the power peak with the shorter tire. Add to that the fact that the smaller tire is slightly lighter in weight so there is less rotational mass. The 28 inch tire would give you the equivalent of a 3.22 axle ratio. The 26 inch tire would give you the equivalent of 3.49.

I have no first hand experience trying both sizes. However, I have seen plenty of guys at the strip wondering why their cars got slower when they put on too tall tires for their gear ratio and engine output.

I agree 100% with that, that's why I went with the 26" drag radial. However if I want to go to bias-ply, which seems to be consensus for manual cars, I only have 1 choice for a new bias-ply in 26" tall, where the 28" has more options. But if I do 28", I think I would need to change my rear gears to 3.55s

I will also keep my eyes open over this winter for some older model MT ET Streets 26"x11.5"x17" that might be slightly used or old stock somewhere. I could probably get a few seasons out of newish tires as I don't go to the track all that often.

 

[brucelinc]

As long as you are changing gears, why not 3.73? Wouldn't that be even better if you go to a 28" tire?

 

[poncho@home]

As long as you are changing gears, why not 3.73? Wouldn't that be even better if you go to a 28" tire?

Yes I it would be better, just worried for my daily driving the rest of the time the 3.73s might be on the edge of too much. Ideally I'd need to drive one and see how it feels around town.

 

[brucelinc]

Yes I it would be better, just worried for my daily driving the rest of the time the 3.73s might be on the edge of too much. Ideally I'd need to drive one and see how it feels around town.

The Performance Package cars come with 3.73s so they must not be too bad. Having said that, I had 3.55 in my 2016 manual and liked it for daily driving.

 

[SVT-DADDY]

3.73's with a 28" tire will be pretty close to 3.31's with a 26" tire with much better traction

Sponsored