Yet Another Re-Gear Thread
05-01-2012, 05:28 PM
#31
I re-geared 3-4-5-6, but I have to admit I am VERY tempted by an 8:32 R&P. I just dont see much downside in having to shift a lot... of course, it would avoid all these low-speed turns taken in the no-power RPM band...
05-02-2012, 12:05 PM
#33
I am sure i'm missing something...
05-02-2012, 05:28 PM
#34
Drifting
Would you mind elaborating? I know one would have to shift more often, but at least second gear would feel right most of the time on low-speed roads. On the highway, I don't see why it would be a problem as you can just go in a higher gear to cruise...
I am sure i'm missing something...
I am sure i'm missing something...
I think it is a wear issue.
05-02-2012, 06:54 PM
#35
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Since 32 devided by 8 is exactly 4, it's something to do with higher wear that occurs when the same gear teeth are always engaging each other (every four revolutions of the pinion gear) instead of a varying mesh pattern that happens when the ratio is not equally divisible such as 31 to 9 (the stock R & P ratio).
05-02-2012, 07:52 PM
#36
a gear set that is not evenly divisible is said to 'hunt',
hunting gears last longer
in addition just changing the cwp of a G50/20 doesn't change the rpm drops
Here's a comparison of a stock /20, a /20 w/ 8:32 cwp and a true racing box a /30, the /20 w/ 8:32 is comparable to the /30 in 6 but much lower geared in 1-5, 1 is now only useful for getting started
here is a comparison of the rpm drops to the next gear which is the other big issue, there are 3 data sets but the drops are not chnged by a cwp change so the 2 /20 data sets lie atop each other. The big drops 1-2 and 2-3 are big sore points, the 4-5 & 5-6 drops aren't too bad and generate fewer complaints
on tracks where only 3 & 4 are used it's not cost effective to re-gear, but when you consider the improved usefulness of all 6 gears it is very worthwhile
hunting gears last longer
in addition just changing the cwp of a G50/20 doesn't change the rpm drops
Here's a comparison of a stock /20, a /20 w/ 8:32 cwp and a true racing box a /30, the /20 w/ 8:32 is comparable to the /30 in 6 but much lower geared in 1-5, 1 is now only useful for getting started
here is a comparison of the rpm drops to the next gear which is the other big issue, there are 3 data sets but the drops are not chnged by a cwp change so the 2 /20 data sets lie atop each other. The big drops 1-2 and 2-3 are big sore points, the 4-5 & 5-6 drops aren't too bad and generate fewer complaints
on tracks where only 3 & 4 are used it's not cost effective to re-gear, but when you consider the improved usefulness of all 6 gears it is very worthwhile
05-02-2012, 10:31 PM
#37
Drifting
05-02-2012, 11:17 PM
#38
Burning Brakes
So, due to some transmission ailments I am thinking about re-gearing the old girl while the transmission is out of the car.
Being on a tight budget I have come up with the following idea based on the two requirements:
Reduce the awful RPM drop into 2nd. Tighten up the gear spread in general, maintain my "cruising gear" for freeway hauls.
To try and keep the cost down I played around with all the different combinations of "stock" gears available and came up with the following gearing chart (Bill V., I stole your chart format... sorry).
The gears are made up of the following:
1st gear: 3.818:1, Stock
2nd gear: 2.250:1, Custom
3rd Gear: 1.560:1, From a G50/21
4th Gear: 1.212:1, From a G50/30
5th Gear: 0.973:1 From a G50/33
6th Gear: 0.775:1, Stock
So for this project i will need 1 custom gear, 3 good used gears and I will re-use my 6th gear. I think the shifting spreads and RPM drops look pretty decent.
What do you guys think though? This will be my first and probably last re-gear so I need to do this right.
Is the steel synchro for 2nd worth the ungodly amount of $$$? Being mostly an autocrosser this is the gear I am most often going in/out of. Is there any negative side to using steel synchros in these transmissions?
Thanks!
Being on a tight budget I have come up with the following idea based on the two requirements:
Reduce the awful RPM drop into 2nd. Tighten up the gear spread in general, maintain my "cruising gear" for freeway hauls.
To try and keep the cost down I played around with all the different combinations of "stock" gears available and came up with the following gearing chart (Bill V., I stole your chart format... sorry).
The gears are made up of the following:
1st gear: 3.818:1, Stock
2nd gear: 2.250:1, Custom
3rd Gear: 1.560:1, From a G50/21
4th Gear: 1.212:1, From a G50/30
5th Gear: 0.973:1 From a G50/33
6th Gear: 0.775:1, Stock
So for this project i will need 1 custom gear, 3 good used gears and I will re-use my 6th gear. I think the shifting spreads and RPM drops look pretty decent.
What do you guys think though? This will be my first and probably last re-gear so I need to do this right.
Is the steel synchro for 2nd worth the ungodly amount of $$$? Being mostly an autocrosser this is the gear I am most often going in/out of. Is there any negative side to using steel synchros in these transmissions?
Thanks!
Jordan
05-03-2012, 09:01 PM
#40
Burning Brakes
Thread Starter
Just got off the phone with Autospeed. They are legit and are actually right down the street from me.
They have a few gears left, but very few ratios to choose from.
2.5:1
2.0:1
1.526:1
1.50:1
and 1.130:1
I might be able to use the 1.526:1 but the rest of the gears are not quite right
Here are is the modified graph plus one more with a different set of frankenstein gears but same 1,2 and 6. It's a little more aggressive... 2nd will be more fun but it will be a bit more manic as well.
They have a few gears left, but very few ratios to choose from.
2.5:1
2.0:1
1.526:1
1.50:1
and 1.130:1
I might be able to use the 1.526:1 but the rest of the gears are not quite right
Here are is the modified graph plus one more with a different set of frankenstein gears but same 1,2 and 6. It's a little more aggressive... 2nd will be more fun but it will be a bit more manic as well.
05-03-2012, 10:48 PM
#42
Burning Brakes
Thread Starter
Jordan,
I didn't see your post. I am VERY interested in getting a ride in your car. Do you also have a LWF?
I am going to out this weekend, otherwise I would have been at the SDR Driving school at Qualcomm. Could we meet sometime next week though?
WindyDog,
Who makes GT gears? I am only familiar with Guard, Albins and Quaife for our cars... or is GT Guard?
If we can get a few people interested in doing re-gears with the same ratios than we might be able to leverage a discount.
I didn't see your post. I am VERY interested in getting a ride in your car. Do you also have a LWF?
I am going to out this weekend, otherwise I would have been at the SDR Driving school at Qualcomm. Could we meet sometime next week though?
WindyDog,
Who makes GT gears? I am only familiar with Guard, Albins and Quaife for our cars... or is GT Guard?
If we can get a few people interested in doing re-gears with the same ratios than we might be able to leverage a discount.
05-04-2012, 12:43 AM
#44
Ed is correct, its Guard. I am also considering the Guard LSD, but for 3k, is it really worth it. I did some research and the LSD I have in my car is junk. I can see that I might have to give up my first born soon.
Some of the guys I talk with tell me a good gearbox cost almost as much as the engine.
Some of the guys I talk with tell me a good gearbox cost almost as much as the engine.
05-04-2012, 12:45 AM
#45
Burning Brakes
Yes I have a LWF also. I'm around this weekend but if you're not hit me up after Wednesday or later as I'm out of town M/T. I'm happy to come North for a drive...way better roads.