HPDE's above stock 4th gear
Jun 8, 2007, 09:56 AM
#31
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in my VIII I find that the gears a set up really nice for watkins glen..
the one thing to remember is that since you're shifting out of 4th at redline it's not like you're landing low down in 5th. I shift 4-5 during the camber change in the middle of the esses and ride out that nice long 5th down the back straight.
the one thing to remember is that since you're shifting out of 4th at redline it's not like you're landing low down in 5th. I shift 4-5 during the camber change in the middle of the esses and ride out that nice long 5th down the back straight.
Jun 8, 2007, 10:22 PM
#32
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The RPM drop from 4th to 5th in my Evo IX is amazingly frustrating. At Thunderhill, Sears Point, and BW, you need to grab fifth at a couple of points and lose lots of accelleration.
The easiest answer is to look at tire revs per mile. The taller the tire, the more speed you'll get out of the car in each gear. I ran the 245/40-18 Toyo RA-1s for a weekend, which were a pretty nice improvement.
For my own car, I'll probably focus on changing the final drive. The car makes more than enough torque when modified that if you go with the HKS final drive, you shouldn't lose all that much in terms of acelleration but will be able to basically drive most tracks in 3rd and 4th gears exclusively.
Just my $0.02.
The easiest answer is to look at tire revs per mile. The taller the tire, the more speed you'll get out of the car in each gear. I ran the 245/40-18 Toyo RA-1s for a weekend, which were a pretty nice improvement.
For my own car, I'll probably focus on changing the final drive. The car makes more than enough torque when modified that if you go with the HKS final drive, you shouldn't lose all that much in terms of acelleration but will be able to basically drive most tracks in 3rd and 4th gears exclusively.
Just my $0.02.
Aug 27, 2007, 01:09 PM
#33
The RPM drop from 4th to 5th in my Evo IX is amazingly frustrating. At Thunderhill, Sears Point, and BW, you need to grab fifth at a couple of points and lose lots of accelleration.
The easiest answer is to look at tire revs per mile. The taller the tire, the more speed you'll get out of the car in each gear. I ran the 245/40-18 Toyo RA-1s for a weekend, which were a pretty nice improvement.
The easiest answer is to look at tire revs per mile. The taller the tire, the more speed you'll get out of the car in each gear. I ran the 245/40-18 Toyo RA-1s for a weekend, which were a pretty nice improvement.
I'm currently running 255/40-17 RA1's on the track. Good, cost-effective and proven setup that I know a lot of people run. The problem I see with them is that the 255/40-17 is slightly smaller than stock so this is causing me more of a issue with shifting into 5th sooner - albeit by like 3-4mph or something. But if I could get something slightly larger than stock, I could hold my 4th gear a few mph longer (net change of maybe 6-7 mph over what I have now) which could be a descent change. Not sure how much would be noticeable?
235/45-17 - 25.4 (stock size)
255/40-17 - 25.0
245/40-18 - 25.6
I also noticed the RA1 is a bit (very tiny big) larger in diameter as compared to the NT01. Just an fyi as they are compared a lot.
I really don't want to start a huge 'what is the best tire/rim setup' type thread. But I am really curious what all tire sizes people are running that are taller than stock. I'm not planning to run spacers or roll/pull fenders at this point personally.
Last edited by boomn29; Aug 30, 2007 at 10:01 AM.
Aug 27, 2007, 02:01 PM
#34
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I tested 255/40-17, 275/40-17, and 245/40-18 RA-1s on my Evo. The 245 offered similar grip to the 255, but with much better gearing. I ended up running the 255 only because I needed more sidewall for Targa, but I plan to run 245/40-18 R888's in time trials next year.
Altering tire size does seem like the simplest way to go about this.
I'm currently running 255/40-17 RA1's on the track. Good, cost-effective and proven setup that I know a lot of people run. The problem I see with them is that the 255/40-17 is slightly smaller than stock so this is causing me more of a issue with shifting into 5th sooner - albeit by like 3-4mph or something. But if I could get something slightly larger than stock, I could hold my 4th gear a few mph longer (net change of maybe 6-7 mph over what I have now) which could be a descent change. Not sure how much would be noticeable?
[B]235/45-17 - 25.4 (stock size)
255/40-17 - 25.0
245/40-18 - 25.6
I also noticed the RA1 is a bit (very tiny big) larger in diameter as compared to the NT01. Just an fyi as they are compared a lot.
I really don't want to start a huge 'what is the best tire/rim setup' type thread. But I am really curious what all tire sizes people are running that are taller than stock. I'm not planning to run spacers or roll/pull fenders at this point personally.
I'm currently running 255/40-17 RA1's on the track. Good, cost-effective and proven setup that I know a lot of people run. The problem I see with them is that the 255/40-17 is slightly smaller than stock so this is causing me more of a issue with shifting into 5th sooner - albeit by like 3-4mph or something. But if I could get something slightly larger than stock, I could hold my 4th gear a few mph longer (net change of maybe 6-7 mph over what I have now) which could be a descent change. Not sure how much would be noticeable?
[B]235/45-17 - 25.4 (stock size)
255/40-17 - 25.0
245/40-18 - 25.6
I also noticed the RA1 is a bit (very tiny big) larger in diameter as compared to the NT01. Just an fyi as they are compared a lot.
I really don't want to start a huge 'what is the best tire/rim setup' type thread. But I am really curious what all tire sizes people are running that are taller than stock. I'm not planning to run spacers or roll/pull fenders at this point personally.
Aug 28, 2007, 01:29 PM
#35
I've been watching the development of the Toyo R888 myself, and am interested in seeing what additional size offerings they put out. Kinda looking for a 245/45-17 right now as I have 17x9 rims. Not sure if that's an option for a good R-comp tire of any brand.
I might have to sport up for some 18's I guess, but don't really want to if I can find a good tire option for my current setup.
Aug 30, 2007, 10:02 AM
#36
Ok, I amassed the top speed @ 7000 and 7500rpms for a 5-speed IX in 4th gear. If you know the formula, you can use the diameter for different gearing.
Supposedly the Toyo R888 will offer more sizes by next year. If anyone has ideas for different tires that are similar to the ones I've listed, post up the info or let me know and I'll add them. I didn't get too crazy with the sizes, nothing in the 275 width since that usually requires fender work and those in for that probably do a ton of research!
..........Tire..............Size................Di ameter......7000......7500......Revs per Mile
Not sure if 3mph would make a noticeable difference really?
Supposedly the Toyo R888 will offer more sizes by next year. If anyone has ideas for different tires that are similar to the ones I've listed, post up the info or let me know and I'll add them. I didn't get too crazy with the sizes, nothing in the 275 width since that usually requires fender work and those in for that probably do a ton of research!
..........Tire..............Size................Di ameter......7000......7500......Revs per Mile
- ......Stock..............235/45-17......25.30......106.9......114.5......822
- .
- BFGoodrich R1......255/40-17......24.80......104.8......112.3......839
- Hancook Z212......255/40-17......24.90......105.2......112.7......834
- ......Nitto NT01......255/40-17......24.92......105.3......112.8......834
- ......Toyo RA1........255/40-17......25.00......105.6......113.2......828
- ......Toya RA1........235/45-17......25.40......107.3......115.0......834
- ......Nitto NT01......245/45-17......25.55......108.0......115.7......813
- ......Nitto NT01......245/40-18......25.55......108.0......115.7......813
- ......Toyo RA1........245/40-18......25.60......108.2......115.9......812
- ......Toyo R888......245/40-18......25.70......108.6......116.3......808
Not sure if 3mph would make a noticeable difference really?
Last edited by boomn29; Sep 7, 2007 at 12:02 PM.
Aug 30, 2007, 02:52 PM
#37
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Nice job! I actually keep a spreadsheet of this stuff. ;-)
That 3 mph could make the difference between banging off the rev limiter for a few seconds (or having to shift) or being able to carry 4th longer. Personally for me it made all the difference in the world at Sears Point and (even worse) at Thunderhill.
That 3 mph could make the difference between banging off the rev limiter for a few seconds (or having to shift) or being able to carry 4th longer. Personally for me it made all the difference in the world at Sears Point and (even worse) at Thunderhill.
Aug 30, 2007, 03:07 PM
#38
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The RPM drop from 4th to 5th in my Evo IX is amazingly frustrating. At Thunderhill, Sears Point, and BW, you need to grab fifth at a couple of points and lose lots of accelleration.
The easiest answer is to look at tire revs per mile. The taller the tire, the more speed you'll get out of the car in each gear. I ran the 245/40-18 Toyo RA-1s for a weekend, which were a pretty nice improvement.
For my own car, I'll probably focus on changing the final drive. The car makes more than enough torque when modified that if you go with the HKS final drive, you shouldn't lose all that much in terms of acelleration but will be able to basically drive most tracks in 3rd and 4th gears exclusively.
Just my $0.02.
The easiest answer is to look at tire revs per mile. The taller the tire, the more speed you'll get out of the car in each gear. I ran the 245/40-18 Toyo RA-1s for a weekend, which were a pretty nice improvement.
For my own car, I'll probably focus on changing the final drive. The car makes more than enough torque when modified that if you go with the HKS final drive, you shouldn't lose all that much in terms of acelleration but will be able to basically drive most tracks in 3rd and 4th gears exclusively.
Just my $0.02.
edit: just noticed the nt01 comes in 245/45-17. I'll definitely be getting those to replace the RA1s. That should give me almost 2% higher top speed.
Last edited by redvolution; Aug 30, 2007 at 03:22 PM.
Sep 1, 2007, 07:57 AM
#41
Even with the IX 4th gear, and 8k redline on stock tires yields you 129mph.
Sep 3, 2007, 07:16 PM
#43
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Just to add more data to the mix -- attached is an Excel spreadsheet with all of the gear ratios we could find for the Evo 5-speed gearbox. The numbers to the right are the drop in RPM when you change gears. You want that number to be as high as possible.
If you look at it, the Evo IX box is really, really good. The only weakness is 5th -- the Evo 7 CR box would be ideal here. The gear ratios in the 6 speed are pretty sweet, but you have to accept how fragile the box is if you want to go that route (not an option for me, as i need longevity over time).
If someone can find me an Evo VII close-ratio box, I'll be ecstatic. Otherwise I'll tune the car specifically for 3rd-4th on track and just call it a day. ;-)
If you look at it, the Evo IX box is really, really good. The only weakness is 5th -- the Evo 7 CR box would be ideal here. The gear ratios in the 6 speed are pretty sweet, but you have to accept how fragile the box is if you want to go that route (not an option for me, as i need longevity over time).
If someone can find me an Evo VII close-ratio box, I'll be ecstatic. Otherwise I'll tune the car specifically for 3rd-4th on track and just call it a day. ;-)
Sep 7, 2007, 10:26 AM
#45
Ok, I amassed the top speed @ 7000 and 7500rpms for a 5-speed IX in 4th gear. If you know the formula, you can use the diameter for different gearing.
..........Tire..............Size................Di ameter......7000......7500......Revs per Mile
..........Tire..............Size................Di ameter......7000......7500......Revs per Mile
- ......Stock..............235/45-17......25.30......106.9......114.5......822
. - BFGoodrich R1......255/40-17......24.80......104.8......112.3......839
- Hancook Z212......255/40-17......24.90......105.2......112.7......834
- ......Nitto NT01......255/40-17......24.92......105.3......112.8......834
- ......Toyo RA1.......255/40-17......25.00.......105.6......113.2......828
- ......Toya RA1.......235/45-17......25.40.......107.3......115.0......834
- ......Nitto NT01......245/45-17......25.55......108.0......115.7......813
Currently running 255/40-17 RA1's and trying to find something to help out 4th gear topend if possible.
.....Or goto 18's; but more weight and a new purchase suck.
Last edited by boomn29; Sep 7, 2007 at 12:01 PM.