Front Runner diameter?

[don_w]

I'm going to be ordering track tires this weekend, and I was planning on using the M/T 26x4.50-15 front runners (#3007) that I had before. But before I click the order button, I was curious about the pros/cons of running a taller front tire, such as the 27.5x4.50-15 front runners (#3009).

For example, there is a 5" difference in circumference. How will one or the other effect reaction times? My gut tells me that the added rollout of the taller tire will slow down RTs (assuming I stage the same depth as before), but should help ETs. Does that seem correct?

Any other thoughts on a 26" tire versus a 27.5" up front?

 

[spyder7724]

I'm going to be ordering track tires this weekend, and I was palnning on using the M/T 26x4.50-15 front runners (#3007) that I had before. But before I click the order button, I was curious about the pros/cons of running a taller front tire, such as the 27.5x4.50-15 front runners (#3009).

For example, there is a 5" difference in circumference. How will one or the other effect reaction times? My gut tells me that the added rollout of the taller tire will slow down RTs (assuming I stage the same depth as before), but should help ETs. Does that seem correct?

Any other thoughts on a 26" tire versus a 27.5" up front?

you are correct. the taller tire will slow r/t's but also will drop e.t.'s thats why you see the stock eliminator guys running 28-29" tall front tires and setting their wheelbase to the maximum 1" stagger. the more rollout you have the quicker the e.t. will be cause the car essentially has a longer running start before the stage beam is broken and the clock starts.
5" is a hell of a lot and may affect your r/t's quite a bit but you'll like what it does for the 60' times

 

[andyman]

you are correct. the taller tire will slow r/t's but also will drop e.t.'s thats why you see the stock eliminator guys running 28-29" tall front tires and setting their wheelbase to the maximum 1" stagger. the more rollout you have the quicker the e.t. will be cause the car essentially has a longer running start before the stage beam is broken and the clock starts.
5" is a hell of a lot and may affect your r/t's quite a bit but you'll like what it does for the 60' times

Thanks for the info, I'll be nabbing a taller tire then!

 

[don_w]

you are correct. the taller tire will slow r/t's but also will drop e.t.'s thats why you see the stock eliminator guys running 28-29" tall front tires and setting their wheelbase to the maximum 1" stagger. the more rollout you have the quicker the e.t. will be cause the car essentially has a longer running start before the stage beam is broken and the clock starts.
5" is a hell of a lot and may affect your r/t's quite a bit but you'll like what it does for the 60' times

Thanks Ron... it seemed logical to me, but I was looking for some confirmation.

Guess I'll just have to hope the increased power will help the car launch quicker, and/or I get better on the tree to keep the RTs respectable. Staging shallower would work to, but that's probably defeating the point of having more rollout.

Also, am I wrong to think that extra 0.75" height in the front will also improve weight transfer a little?

 

[spyder7724]

Thanks Ron... it seemed logical to me, but I was looking for some confirmation.

Guess I'll just have to hope the increased power will help the car launch quicker, and/or I get better on the tree to keep the RTs respectable. Staging shallower would work to, but that's probably defeating the point of having more rollout.

Also, am I wrong to think that extra 0.75" height in the front will also improve weight transfer a little?

I doubt it will make much difference but in theory yes it will raise the front end slightly which should help transfer. I think thats one thing these cars can use less of. the way the suspension is setup causes them to squat and actually wastes time raising the front and squashing the rear. my car is quicker with the front struts set on a really tight setting. thats something you can use to play with reaction times as well. i'll adjust front tire pressure and/or play with strut settings to dial in my r/t's at different tracks. it allows me to launch at the same rpm everywhere so i don't have to worry about that inconsistency.

 

[don_w]

What are you using on your rear suspension? I'm currently running adj BMR LCAs (rod end) with the Steeda anti-squat bracket, Strange adj shocks, a BMR UCA, BMR adj panhard, with stock springs. I'll be adding the BMR extreme anti-roll bar before I hit the track again, too. I'm hoping most of the squat will be gone... but we'll see.

 

[don_w]

Any other thoughts on the front runner diameter before I click the order button at Summit?

 

[spyder7724]

Any other thoughts on the front runner diameter before I click the order button at Summit?

it would also depend on what size rear you run. a 28" tall front would look silly with a 26" tall rear tire but now that i switched to a 28" rear tire i think mine would look better with a 27" or 28" front tire. i just can't lower it enough in the front so that the 26"tire fills the wheelwell. if i do then i can't open my doors on the trailer
on my rear suspension i have a steeda adjustable street UCA and J&M non adjustable lowers and use my bite bars to prevent any squat. They allow me to run my rear shocks set on full loose. I still haven't found a good compromise for street and track with the bars. the setup that works best at the track is a bit noisy on the street and once i reduce the noise for street driving the track performance suffers. They may wind up being a track oriented piece.

 

[don_w]

I just ordered a set of 28x11.50-15 M/T slicks to go along with the 27.5x4.50-15 front runners.

And thanks for the update on the bite bars. I was wondering how those were working out.

 

[scramblr]

Yeah I know, holy hell old thread. But at least I searched.

So if running a 28" tire in the rear, what are the pro's/con's between a 27.5" and a 28" front runner? Looking at the MT ET 3002 28.0/4.5-15 or 3009 27.5/4.5-15.

 

[don_w]

Yeah I know, holy hell old thread. But at least I searched.

So if running a 28" tire in the rear, what are the pro's/con's between a 27.5" and a 28" front runner? Looking at the MT ET 3002 28.0/4.5-15 or 3009 27.5/4.5-15.

Those are so close, you wouldn't reaaly notice a difference.

 

[scramblr]

That's what I figured. Aside from the 1.2" in diameter the sidewall from 7.0 to 7.2 is the only other difference. Must be a reason they make these two with the specs being so close.

The rear Holeshot's I just got have 26" tires on them. I'm picking up two front wheels and need to get the tires as well. I'll be switching to a 28" tire in the rear when I wear these out, so figured I may as well get the front runners that will complement the upcoming 28" rear tires.

 

[ChevyKiller]

I didn't really pay attention to RT's too much (but I am now...lol) but I will tell you that I had 26" fronts and switching to the 28" netted me considerably lower 60's and helped my launch considerably. Bear in mind though that I use a pretty tall rear (29")

 

[US-1]

I'm not saying a damn thing.

 

[don_w]

I'm not saying a damn thing.

<<<< Making a note of this once-in-a-lifetime event....

 

[Freaknazty]

<<<< Making a note of this once-in-a-lifetime event....

 

[US-1]

And I've got very greedy, self-centered reasons to keep my mouth shut as well. One of you might be in the other lane someday.

 

[Born To Run]

Tire

I'm going to be ordering track tires this weekend, and I was planning on using the M/T 26x4.50-15 front runners (#3007) that I had before. But before I click the order button, I was curious about the pros/cons of running a taller front tire, such as the 27.5x4.50-15 front runners (#3009).

For example, there is a 5" difference in circumference. How will one or the other effect reaction times? My gut tells me that the added rollout of the taller tire will slow down RTs (assuming I stage the same depth as before), but should help ETs. Does that seem correct?

Any other thoughts on a 26" tire versus a 27.5" up front?

I went with the 27.5" on the fronts which is actually smaller than 27.5".
My purpose was stance & weight transfer,looks etc.
What is the actual size of the 26",MT have some weird measurements vs what they call them.

 

[don_w]

I went with the 27.5" on the fronts which is actually smaller than 27.5".
My purpose was stance & weight transfer,looks etc.
What is the actual size of the 26",MT have some weird measurements vs what they call them.

I also went with the 27.5", which are really listed as 27.3". I've had them for a few months now, and really like them.

 

[Born To Run]

Tire

I also went with the 27.5", which are really listed as 27.3". I've had them for a few months now, and really like them.

3 weeks till i get to try them out up here.
What air pressure did you run in the fronts of these 27.5 MT?