it in 2nd 
Gearing: Will it be enough?
Thread Starter
Instructor
Joined: Sep 2004
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Gearing: Will it be enough?
To determine my differential ratio I turned the "input" yoke and determined how many turns of that would cause a complete revolution of one of the half-shaft yokes. If I did it right, it was somewhere along the lines of 3 revolutions. So I'm assuming my differential ratio is 3.08 or somewhere around there. Because of this I opted for the following higher gear ratio for my 5 speed.
1st 2nd 3rd 4th 5th
3.27 1.98 1.34 1.00 .68
My question is will this be enough to offset the rear-end and push me back into my seat? I'm not real concerned about the top-end as it wont be a daily driver but I'm definently concerned about my acceleration being weak. Btw I'm putting a RamJet 350 PFI in.
Bry
1st 2nd 3rd 4th 5th
3.27 1.98 1.34 1.00 .68
My question is will this be enough to offset the rear-end and push me back into my seat? I'm not real concerned about the top-end as it wont be a daily driver but I'm definently concerned about my acceleration being weak. Btw I'm putting a RamJet 350 PFI in.
Bry
Race Director
Joined: Apr 2000
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
That is wide ratio with that first gear and some might not like it because of the bigger difference between first and second. It will feel like a a a 3.90 gear in first but will feel like a 3.08 in second.
I opted for the 2.8 first gear and am going with a 3.55 rear end, I also wanted the 650HP unit so I had no choice
I opted for the 2.8 first gear and am going with a 3.55 rear end, I also wanted the 650HP unit so I had no choice
Race Director
Joined: Dec 1999
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From: Forked River NJ
I have 3.70 gears with my TKO. My 5th gear ratio is 2.51. This is real good on the highway 2200 at 70 mph. Jus tabout right. i think a 3.08 is a little weak going through the gears. 1st would be OK but after that unless you have a ton of torque is going to be doggy. 3.55 or 3.70 seems to be good with a TKO.
Thread Starter
Instructor
Joined: Sep 2004
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It puts out 400ftlbs but still I'm worried. 3.5's or 3.7's are what I wanted. How difficult/expensive would a gear swap be? Do people usually just turn in their entire Differential for another one? 
Bry
Bry
Team Owner
Joined: Jun 2004
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From: Smile, it's just the internet.
I've got 2.73's behind a 427/TKO-600 combo. 2.73 is TOO LOW. It'll easily break loose in 1st, but second isn't quite as punchy as I'd like. 5th is almost a total waste since I'm around 1500 rpm at 65. It cruises better in 4th, which makes sense because the 2.73 was the "economy" gearing. I'm going up to 3.5 ASAP.
If I were you, I would "move on up" to a 3.5 behind that SB.
I, too, am curious how involved a gear swap is...
If I were you, I would "move on up" to a 3.5 behind that SB.
I, too, am curious how involved a gear swap is...
Race Director
Joined: Dec 1999
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From: Forked River NJ
Originally Posted by Bryan8412_2
It puts out 400ftlbs but still I'm worried. 3.5's or 3.7's are what I wanted. How difficult/expensive would a gear swap be? Do people usually just turn in their entire Differential for another one?
Bry
Bry
Race Director
Joined: Apr 2000
Posts: 17,676
Likes: 201
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Swap the punkin with Van Steel that's waht I am going to do, they also have a rebuild service, maybe a group purchase, let's get 10 together and make Dan a deal he can't refuse ???
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Racer
Joined: Mar 2003
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From: Mechanicsville VA
Fairly easy to change the gear ratios.
However, your low gear multiplied by the rear gear gives you a ratio of 10:1, which is 25% better than the minimum recommended ratio of 8:1. This allows a good launch without burning the clutch.
No doubt that the gears of 3.5 and 3.9 or so will give you more launch, but it's all a compromise on fuel efficiency vs. performance.
What you want and what I want may be different things.
Good luck.
However, your low gear multiplied by the rear gear gives you a ratio of 10:1, which is 25% better than the minimum recommended ratio of 8:1. This allows a good launch without burning the clutch.
No doubt that the gears of 3.5 and 3.9 or so will give you more launch, but it's all a compromise on fuel efficiency vs. performance.
What you want and what I want may be different things.
Good luck.
Race Director
Joined: Dec 1999
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From: Forked River NJ
Originally Posted by PureSilver
No doubt that the gears of 3.5 and 3.9 or so will give you more launch, but it's all a compromise on fuel efficiency vs. performance.
What you want and what I want may be different things.
Good luck.
What you want and what I want may be different things.
Good luck.
Drifting
Joined: Jul 2004
Posts: 1,360
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From: COVINGTON LA
Originally Posted by MotorHead
Swap the punkin with Van Steel that's waht I am going to do, they also have a rebuild service, maybe a group purchase, let's get 10 together and make Dan a deal he can't refuse ???
Keith
I'm interested!
Premium Supporting Vendor
Joined: May 2000
Posts: 4,312
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From: Clearwater FL
I'm sure we can work something out for you guys. The only thing is that I will have to rebuild your units. I don't have enough here to do exchange units. Plus this will save you some $.
Race Director
Joined: Apr 2000
Posts: 17,676
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
I would be interested in sending you mine over the winter, I was initially going to go with a older rear end retrofit but I am getting a new Tremec and I just bought Hooker sidepipes so I've already broke the bank for next year.
Somone else start a thread on "Vansteel differential rebuild/exhange group purchase" and see who's interested, I started the last one on the trannys
Somone else start a thread on "Vansteel differential rebuild/exhange group purchase" and see who's interested, I started the last one on the trannys