Hitting redline during AX?

[ksconekiller]

After posting this up, I was reading the article closer. I had only jumped to the end for the conclusion before. I think more then anything its showing the importance of the right wheel for the tire being used. I mean going down to a 6" rim for a 225....

That’s a typo. It was a 16x7 wheel. We know this because he had to use a wheel that was stock width because of HS rules, but more importantly, Enkei doesn’t make that wheel in a 16x6 size. Besides, if the wheels were truly 1” narrower each, the stack of the 225 tires would not have been taller if they were pinched that far. I think the >1 second difference in tires was mostly due to that particular course. The lighter weight and wider contact patch should compensate for the taller height on most layouts, especially ones that see higher speeds.

 

[M-Sport fan]

That’s a typo. It was a 16x7 wheel. We know this because he had to use a wheel that was stock width because of HS rules, but more importantly, Enkei doesn’t make that wheel in a 16x6 size. Besides, if the wheels were truly 1” narrower each, the stack of the 225 tires would not have been taller if they were pinched that far. I think the >1 second difference in tires was mostly due to that particular course. The lighter weight and wider contact patch should compensate for the taller height on most layouts, especially ones that see higher speeds.

Yeah, the facebook comments below the article must've been ALL non FiST people, otherwise they would have known that the RPF1 is not made in a 6" width for our rides (or ANY other rides for that matter? ), and only in a 7" width (until the new OAKOS group buy for them in 16x8 ).

What is encouraging for me from that article is that the 225/45-16 A052 did not rub at all, given the factory ride height/springs they were using (those trick, big $$$$ MCS coil overs actually use the FACTORY springs on them to be H/Stock legal ) despite being the widest DOT tire made in the size as far as tread width goes.

Now since I am going to be using them on Dekagrams, at 8" wide (don't do Solo), I am hoping that does not eat up that minuscule clearance difference they were speaking of when they are on 16x7 RPF1s (what is the ET of the 16x7 RPF1s again???).

 

[Rexracer]

I forgot to share. Another local FiSTer went to 245/45R16 R888r's last year, on stock suspesion. He reports little/no rubbing...

 

[Rexracer]

(what is the ET of the 16x7 RPF1s again???).

43mm

 

[Rexracer]

That’s a typo. It was a 16x7 wheel. We know this because he had to use a wheel that was stock width because of HS rules, but more importantly, Enkei doesn’t make that wheel in a 16x6 size. Besides, if the wheels were truly 1” narrower each, the stack of the 225 tires would not have been taller if they were pinched that far. I think the >1 second difference in tires was mostly due to that particular course. The lighter weight and wider contact patch should compensate for the taller height on most layouts, especially ones that see higher speeds.

Yeah thats a great point, not sure why they wouldnt respond to note that mistake. But at the end of the day, I think that particular course was the main reason for the slower time.

 

[faust]

I forgot to share. Another local FiSTer went to 245/45R16 R888r's last year, on stock suspesion. He reports little/no rubbing...

Wow. Wouldn't have guessed that.

 

[M-Sport fan]

Wow. Wouldn't have guessed that.

Yes, at an 8.5" tread width, and a 24.6" height, that does seem impossible to not rub, regardless of the ride height.

 

[M-Sport fan]

I forgot to share. Another local FiSTer went to 245/45R16 R888r's last year, on stock suspension. He reports little/no rubbing...

Those are 16x7 Motegis?

 

[Rexracer]

Thats what they look like to me.

He said "
I ran a 225/50/16 first. It rubbed on the top of the tire on the fender liner. Then went to a 225/45/16 and it didn't rub anymore. Now I'm at a 245 and it barely rubs and only if I hit a huge bump. Same wheel everytime.
Mind you I'm on stock suspension.
"

 

[tri-pedaler]

Reviving this thread after an event that had me at the rev limited at a few points. My current thought is that 2.5-3 seconds is long enough to go to 3rd. And the over-rev function to 6500 only lasts for 3 seconds, then it’s back down to 6250.

others have a rule of thumb for how long they stay on the limiter before shifting? @CSM?

 

[CSM]

Reviving this thread after an event that had me at the rev limited at a few points. My current thought is that 2.5-3 seconds is long enough to go to 3rd. And the over-rev function to 6500 only lasts for 3 seconds, then it’s back down to 6250.

others have a rule of thumb for how long they stay on the limiter before shifting? @CSM?

No rule of thumb for me. If I'm on the limiter in 2nd in my SSC car (59mph) for more than say, 1 second, I'll usually consider a shift to third. But a lot of it depends on what the next element is. If it's a tight slow element then sometimes it isn't worth it since you can easily blow a corner. Our day 2 plane side course at Nationals this year was a good example. There was a section where we could shift to third, it was worth about .2-.3 seconds, but it was REALLY easy to completely blow the next element. So most people just didn't bother.

If you aren't good at heel toe downshifting I'd recommend not even bothering unless it is BLATANTLY obvious going to third will gain time.

 

[tri-pedaler]

No rule of thumb for me. If I'm on the limiter in 2nd in my SSC car (59mph) for more than say, 1 second, I'll usually consider a shift to third. But a lot of it depends on what the next element is. If it's a tight slow element then sometimes it isn't worth it since you can easily blow a corner. Our day 2 plane side course at Nationals this year was a good example. There was a section where we could shift to third, it was worth about .2-.3 seconds, but it was REALLY easy to completely blow the next element. So most people just didn't bother.

If you aren't good at heel toe downshifting I'd recommend not even bothering unless it is BLATANTLY obvious going to third will gain time.

Good thinking. Hee- toe is easy enough on the street, it’s when you’re braking hard. Then you need pedal feel AND to blip deep with a lot of revs. That’s tricky for me and you just can’t practice that on the road.

 

[kivnul]

For me, when it wasn't obvious that 3rd was the way to go, I just tried both to see what was faster. This works well when you get 6-8 runs in a day. If you only get 3 runs, I'd stick to 2nd gear. (side note, I run slightly oversize tires and a 7k rpm limiter)

 

[Rexracer]

Reviving this thread after an event that had me at the rev limited at a few points. My current thought is that 2.5-3 seconds is long enough to go to 3rd. And the over-rev function to 6500 only lasts for 3 seconds, then it’s back down to 6250.

others have a rule of thumb for how long they stay on the limiter before shifting? @CSM?

No rule of thumb, as tri-pedaler said, it all depends what the next element is. I will say I found that I started going to 3rd more willingly, if I could get into it earlier. These motors make max torque at what 4500rpm? So in a section that I maybe on redline for only 1 second, but if there is a section I can go to 3rd 1-2 seconds before I would hit redline, then I am in 3rd for 3ish seconds pulling hard, it was worth it.
The big thing, when you do 3rd, you will be going faster into that next element, so your braking points need to back up to match.

 

[Rexracer]

. Our day 2 plane side course at Nationals this year was a good example. There was a section where we could shift to third, it was worth about .2-.3 seconds, but it was REALLY easy to completely blow the next element. .

This is exactly what I did, 1st run redline for hours in that spot, 2nd run, shift to 3rd, way to much speed before the wallums, 3rd run, got that right, but blew another section. Rough event for me, but well worth it for the experiance.

 

[tri-pedaler]

No rule of thumb for me. If I'm on the limiter in 2nd in my SSC car (59mph) for more than say, 1 second, I'll usually consider a shift to third. But a lot of it depends on what the next element is. If it's a tight slow element then sometimes it isn't worth it since you can easily blow a corner. Our day 2 plane side course at Nationals this year was a good example. There was a section where we could shift to third, it was worth about .2-.3 seconds, but it was REALLY easy to completely blow the next element. So most people just didn't bother.

If you aren't good at heel toe downshifting I'd recommend not even bothering unless it is BLATANTLY obvious going to third will gain time.

Myea

This is exactly what I did, 1st run redline for hours in that spot, 2nd run, shift to 3rd, way to much speed before the wallums, 3rd run, got that right, but blew another section. Rough event for me, but well worth it for the experiance.

I plan to try it at a regional event with 5-6 runs. At a national tour event with only 3 runs it sounds too risky.

 

[tri-pedaler]

No rule of thumb, as tri-pedaler said, it all depends what the next element is. I will say I found that I started going to 3rd more willingly, if I could get into it earlier. These motors make max torque at what 4500rpm? So in a section that I maybe on redline for only 1 second, but if there is a section I can go to 3rd 1-2 seconds before I would hit redline, then I am in 3rd for 3ish seconds pulling hard, it was worth it.
The big thing, when you do 3rd, you will be going faster into that next element, so your braking points need to back up to match.

Interesting about the “next element.” I’m guessing if it’s a hard braking zone you can get back to 2nd safely (we’ll, hopefully), but if the straight takes you into a slalom then there’s nowhere to downshift?