Re gearing
09-09-2012, 12:18 PM
#31
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77'3.6vram: /32 looks lovely except I really like my stock 3.818 1st gear for dealing with traffic and steep hills, so I'm intentionally trying to design a set that keeps that 3.818 gear and works up form there. The 3.818 much more usable than the tall 1st on my old '84 915 transmission.
Last edited by callipygian 911; 09-09-2012 at 02:08 PM.
09-09-2012, 12:29 PM
#32
Rennlist Member
Great thread
Bill and others,
Thanks so much for your contributions to the thread. It looks like Jordon may have it figured out pretty well.
This thread was worth the price of admission.
Thanks so much for your contributions to the thread. It looks like Jordon may have it figured out pretty well.
This thread was worth the price of admission.
09-09-2012, 01:21 PM
#33
Rennlist Member
I picked these out with the exact same goal. I'd say my selections are a little more aggressive (closer) even than the ones you have installed, ignoring 6th of course. Also, Guard Trans no longer offers 1.650 for the 993 gears, but it does still offer all of the other ratios you have, besides 3rd is the one I'm puzzling over.
Still, with the ratios I'm asking about, I'm curious which of the two choices for 3rd gear would be a better fit with the overall 1 -5 scheme. I realize they're pretty darn close, but I was wondering what the regear experts think.
As an aside to explain my desire to retain the stock 6th gear: I live in San Diego as you can see from my avatar info, where almost everyone drives 75 - 85 mph on the freeways. I commute about 20 miles to work and I spend almost all of that commute in 6th gear @ 2500 - 3500 rpms. Never had a ticket in the past 10 years of living here either (knock on wood).
Still, with the ratios I'm asking about, I'm curious which of the two choices for 3rd gear would be a better fit with the overall 1 -5 scheme. I realize they're pretty darn close, but I was wondering what the regear experts think.
As an aside to explain my desire to retain the stock 6th gear: I live in San Diego as you can see from my avatar info, where almost everyone drives 75 - 85 mph on the freeways. I commute about 20 miles to work and I spend almost all of that commute in 6th gear @ 2500 - 3500 rpms. Never had a ticket in the past 10 years of living here either (knock on wood).
09-09-2012, 01:26 PM
#34
Rennlist Member
Anyone in the Bay Area interested is most welcome to try my set-up. All in all, my goal was to be more aggressive than stock Euro and this setup fit my daily driving PERFECTLY, as well as my auto-cross and track outings!
09-09-2012, 10:23 PM
#38
Rennlist Member
Treat for Bill....
Bill has out done himself...didn't think it could happen. Not to be obsequious, but I suspect a book could be composed with Bill's posts to Rennlist.
My next trip East, sometime in the Fall, specifics to be determined, I am buying Bill a nice steak dinner with a good red wine, or whatever he wants. I will bring the wine from California.
Incredible information.....
My next trip East, sometime in the Fall, specifics to be determined, I am buying Bill a nice steak dinner with a good red wine, or whatever he wants. I will bring the wine from California.
Incredible information.....
09-09-2012, 10:46 PM
#39
84' 915 mated to 98'Vram
77'3.6vram: /32 looks lovely except I really like my stock 3.818 1st gear for dealing with traffic and steep hills, so I'm intentionally trying to design a set that keeps that 3.818 gear and works up form there. The 3.818 much more usable than the tall 1st on my old '84 915 transmission.
09-09-2012, 11:10 PM
#40
Pro
+1
Using his charts as a guide I crafted my own excel spreadsheet to do the same. It really made it helpful so I could tweak things such as tire sizes and ratios and immediately see how it changed RPM drop and speeds at 6800RPM. As reference I ended up with 3.154 / 2.176 / 1.632 / 1.308 / 1.083 / 0.921 with steel synchros and billet shift forks, applicable for pacific northwest tracks (Jeff tells me) and autocross.
Using his charts as a guide I crafted my own excel spreadsheet to do the same. It really made it helpful so I could tweak things such as tire sizes and ratios and immediately see how it changed RPM drop and speeds at 6800RPM. As reference I ended up with 3.154 / 2.176 / 1.632 / 1.308 / 1.083 / 0.921 with steel synchros and billet shift forks, applicable for pacific northwest tracks (Jeff tells me) and autocross.
09-09-2012, 11:55 PM
#41
Burning Brakes
Nice selections, Jordan! That gearing is very close indeed to what I want. Do you have any subjective opinions on this gearbox? How tolerable is the 1st to 2nd drop?
77'3.6vram: /32 looks lovely except I really like my stock 3.818 1st gear for dealing with traffic and steep hills, so I'm intentionally trying to design a set that keeps that 3.818 gear and works up form there. The 3.818 much more usable than the tall 1st on my old '84 915 transmission.
77'3.6vram: /32 looks lovely except I really like my stock 3.818 1st gear for dealing with traffic and steep hills, so I'm intentionally trying to design a set that keeps that 3.818 gear and works up form there. The 3.818 much more usable than the tall 1st on my old '84 915 transmission.
09-09-2012, 11:57 PM
#42
Burning Brakes
+1
Using his charts as a guide I crafted my own excel spreadsheet to do the same. It really made it helpful so I could tweak things such as tire sizes and ratios and immediately see how it changed RPM drop and speeds at 6800RPM. As reference I ended up with 3.154 / 2.176 / 1.632 / 1.308 / 1.083 / 0.921 with steel synchros and billet shift forks, applicable for pacific northwest tracks (Jeff tells me) and autocross.
Using his charts as a guide I crafted my own excel spreadsheet to do the same. It really made it helpful so I could tweak things such as tire sizes and ratios and immediately see how it changed RPM drop and speeds at 6800RPM. As reference I ended up with 3.154 / 2.176 / 1.632 / 1.308 / 1.083 / 0.921 with steel synchros and billet shift forks, applicable for pacific northwest tracks (Jeff tells me) and autocross.
09-10-2012, 02:01 AM
#43
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SWEET FANCY MOSES! Thanks again Bill! These charts are extremely helpful. One point of confusion: why would the max speed in 6th gear be different when the ratios should be identical comparing the /20 with my own scheme, ie I was planning to re-use the 1st and 6th gears from my stock tranny?
Edit: I think I figured it out. You entered 7000 as my redline instead of 6800.
Regardless, it seems like Jordan's gearset or my own picks should fulfill my starting parameters pretty well, with Jordan's set having a slight edge. I believe I will use these if all ratios remain available.
Jordan: that would be great! I'd love to take you up on your offer sometime in the near future. I'll PM you my cell and maybe we could meet up sometime.
77'3.6vram: I am guessing that your 1977 911 is a lot lighter than my 1995 993 and would not suffer from a tall first in quite the same manner. Sounds like an awfully fun car, though.
Nollie: any chance you might send me a copy of your excel template?
Rennlist is a remarkable place. Lots of knowlegable folks here. I am humbled by your generosity!
-Josh
Edit: I think I figured it out. You entered 7000 as my redline instead of 6800.
Regardless, it seems like Jordan's gearset or my own picks should fulfill my starting parameters pretty well, with Jordan's set having a slight edge. I believe I will use these if all ratios remain available.
Jordan: that would be great! I'd love to take you up on your offer sometime in the near future. I'll PM you my cell and maybe we could meet up sometime.
77'3.6vram: I am guessing that your 1977 911 is a lot lighter than my 1995 993 and would not suffer from a tall first in quite the same manner. Sounds like an awfully fun car, though.
Nollie: any chance you might send me a copy of your excel template?
Rennlist is a remarkable place. Lots of knowlegable folks here. I am humbled by your generosity!
-Josh
Last edited by callipygian 911; 09-10-2012 at 02:22 AM.
09-10-2012, 08:40 AM
#45
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Noticing the quote Bill used to start the thread (from Martin).
Despite all of the wonderful information here, please do note that Martin seemed to indicate that he may be interested in ultimately moving into PCA racing.
If you re-gear, you will not be running in either stock or prepared classes - regardless of the alphabet (G, H, I or J).
A re-geared tranny will automatically put you into one of the the GT classes (probably GT4) where you will not be competetive without major engine work, massive weight loss, a top of the line suspension and aero.
That said, I LOVE my tranny (a five speed), and bit the bullet to run GT4 in my racecar.
Great thread.
Despite all of the wonderful information here, please do note that Martin seemed to indicate that he may be interested in ultimately moving into PCA racing.
If you re-gear, you will not be running in either stock or prepared classes - regardless of the alphabet (G, H, I or J).
A re-geared tranny will automatically put you into one of the the GT classes (probably GT4) where you will not be competetive without major engine work, massive weight loss, a top of the line suspension and aero.
That said, I LOVE my tranny (a five speed), and bit the bullet to run GT4 in my racecar.
Great thread.