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How much difference do gears REALLY make?

  • Thread starter Thread starter The Dan
  • Start date Start date Nov 8, 2004
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1967coupe

New Member
Feb 25, 2004
109
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Wausau, WI
Nov 11, 2004
#41
  • Nov 11, 2004
  • #41
I'm getting my 9" w/3.89's installed on Monday. I can't wait to feel the difference along with the T5. Car was originally a 3spd. with 2.79 open.
 
T

The Dan

New Member
Jul 16, 2003
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Orange County, CA
Nov 11, 2004
#42
  • Nov 11, 2004
  • #42
OK, 9" it is. I'm going to call Currie today to get a quote. I love SoCal, sometimes, as Currie is only 30 min. from me.

This post has been great, and I've deceided on a 9" with 3.55 gears, and I think a locker, as the limited slip diffs. sound like they are prone to fail after some abuse. I hope the difference is everything I've heard it will be. Time shall tell.
 

reenmachine

20+ Year Stangneter
Jun 27, 2004
1,258
2
38
Montrose, CA
Nov 11, 2004
#43
  • Nov 11, 2004
  • #43
The Dan said:
OK, 9" it is. I'm going to call Currie today to get a quote. I love SoCal, sometimes, as Currie is only 30 min. from me.

This post has been great, and I've deceided on a 9" with 3.55 gears, and I think a locker, as the limited slip diffs. sound like they are prone to fail after some abuse. I hope the difference is everything I've heard it will be. Time shall tell.
Click to expand...
I believe that with a 9" you'll get 3.50, not 3.55 (basically the same). Also, don't give up on the limited-slip, and make sure you know what you're getting into with a locker on a primarily street-driven car.

Currie will be able to answer all of your questions and educate you about the finer points of what may be best for you. Have an open mind when you call them!
 

reenmachine

20+ Year Stangneter
Jun 27, 2004
1,258
2
38
Montrose, CA
Nov 11, 2004
#44
  • Nov 11, 2004
  • #44
Oh, and make sure you check out the owner's 'Stang while you're there, if it's around. 65 or 6, 5.0 EFI, Total Control front and rear with a trick aluminum 9" 3rd member in an aluminum housing. It's nice.
 

Edbert

Founding Member
Jul 13, 2002
3,548
32
109
Austin TX
Nov 11, 2004
#45
  • Nov 11, 2004
  • #45
3.55:1 is about as high as I'd go in a non overdrive car that sees any significant highway mileage. 3.70:1 is debatable of course. Add an overdrive tranny to the mix however and everything changes. I have a 3.89:1 in my AOD equipped car and I may have not gone high enough. My cruise RPM at 60 should net nearly 20 MPG though. Here's a chart I made that will help show the differences:
http://www.edbert.net/rpm_chart.htm
 

Edbert

Founding Member
Jul 13, 2002
3,548
32
109
Austin TX
Nov 11, 2004
#46
  • Nov 11, 2004
  • #46
Another tidbit concerning the best gear ratios. If you ever want to take your car to the dragstrip, calculate an approximate trap speed you hope/expect to acheive one you can hook up and find the right ratio that will put you at the engine's peak horsepower RPM right at the finish line. If you have an OD tranny calculate for 3rd gear auto or 4th gear manual (if you have a 6-speed you don't need to read this...and I hate you ).
 

blue66tang

Founding Member
Jan 20, 2001
1,092
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Medford, OR
Nov 11, 2004
#47
  • Nov 11, 2004
  • #47
The Dan said:
OK, 9" it is. I'm going to call Currie today to get a quote. I love SoCal, sometimes, as Currie is only 30 min. from me.

This post has been great, and I've deceided on a 9" with 3.55 gears, and I think a locker, as the limited slip diffs. sound like they are prone to fail after some abuse. I hope the difference is everything I've heard it will be. Time shall tell.
Click to expand...

I have a detroit locker in my car. If you wont be doing any racing and drive your car all the time. I would look into getting a beefed up limited. The locker deffinately makes a fairly loud clicking around corners. I like it because i drive my car about once every month or less, and i do a fair bit of drag racing ( well i would if i had the time during the summer). So if you know anybody witha locker in their car, go take a ride with them Heck if you were by me. I would give you a ride. Let me tell ya, the lockers arnt good for dates!

Anybody want to help me post that vid, i need somebody to host it for me.
 
N

nosaj122081

New Member
Mar 5, 2003
202
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West Virginia
Nov 11, 2004
#48
  • Nov 11, 2004
  • #48
blue66tang said:
I have a detroit locker in my car. If you wont be doing any racing and drive your car all the time. I would look into getting a beefed up limited. The locker deffinately makes a fairly loud clicking around corners. I like it because i drive my car about once every month or less, and i do a fair bit of drag racing ( well i would if i had the time during the summer). So if you know anybody witha locker in their car, go take a ride with them Heck if you were by me. I would give you a ride. Let me tell ya, the lockers arnt good for dates!

Anybody want to help me post that vid, i need somebody to host it for me.
Click to expand...

How old is your Locker? The new Detroit Lockers you get through Summit Racing have been mildy redesigned, the result being very little, if any, noise. I bought mine in '02, I think, from them, and it doesn't EVER click. The only reason I know its there is when I feel it lock or unlock when I'm getting on it through turns, and the occasional tire bark when in a parking lot. Other than that its quiet and has very good street manners. After having the Locker rear, I would never even consider a LSD again, I'm so impressed with the Locker.
 

blue66tang

Founding Member
Jan 20, 2001
1,092
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0
Medford, OR
Nov 11, 2004
#49
  • Nov 11, 2004
  • #49
nosaj122081 said:
How old is your Locker? The new Detroit Lockers you get through Summit Racing have been mildy redesigned, the result being very little, if any, noise. I bought mine in '02, I think, from them, and it doesn't EVER click. The only reason I know its there is when I feel it lock or unlock when I'm getting on it through turns, and the occasional tire bark when in a parking lot. Other than that its quiet and has very good street manners. After having the Locker rear, I would never even consider a LSD again, I'm so impressed with the Locker.
Click to expand...

Im not sure. All iknow is it came from a nascar team and they used a stronger Nascar type locker. I might be able to find the site that the part # was listed on. I looked it up and it deffenately was a nascar locker.
 

blue66tang

Founding Member
Jan 20, 2001
1,092
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0
Medford, OR
Nov 11, 2004
#50
  • Nov 11, 2004
  • #50
just found it.
http://www.reiderracing.com/detroitlockerapp2.htm

part # 187n 158A
 
N

nosaj122081

New Member
Mar 5, 2003
202
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0
West Virginia
Nov 11, 2004
#51
  • Nov 11, 2004
  • #51
Ahh, I'd bet its NASCAR heritage had alot to do with its street manners, they don't worry too much about that for some reason ... Heres the one I ran/run:
http://store.summitracing.com/partd...28&N=110&Ntk=KeywordSearch&Ntt=detroit+locker

It is quiet as a mouse honestly... Unless I don't want it to be .
 

blue66tang

Founding Member
Jan 20, 2001
1,092
0
0
Medford, OR
Nov 11, 2004
#52
  • Nov 11, 2004
  • #52
maybe mine will quiet down. I only have about 40 miles on it. I threw it all together, had it done by 5:15 got cleaned up and picked my date up at 6:00. So a night of just driving in town (about 40) miles is all it has on it, and the gears too.
 
M

MistaMadMike

New Member
Oct 26, 2004
30
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0
Nov 11, 2004
#53
  • Nov 11, 2004
  • #53
good choice..
Auto=3.73's
Manual=4.10/4.11
 

Edbert

Founding Member
Jul 13, 2002
3,548
32
109
Austin TX
Nov 12, 2004
#54
  • Nov 12, 2004
  • #54
blue66tang said:
Anybody want to help me post that vid, i need somebody to host it for me.
Click to expand...
I can help, at least temporarily, how big is it?
 

blue66tang

Founding Member
Jan 20, 2001
1,092
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0
Medford, OR
Nov 12, 2004
#55
  • Nov 12, 2004
  • #55
One is 3.64 and the other 3.69.
 

Edbert

Founding Member
Jul 13, 2002
3,548
32
109
Austin TX
Nov 12, 2004
#56
  • Nov 12, 2004
  • #56
Check your PMs. If you can email them to that address I'll post them on Sunday or Monday. I am at work now and will be hunting this weekend, leaving town when I get home.
 

blue66tang

Founding Member
Jan 20, 2001
1,092
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0
Medford, OR
Nov 12, 2004
#57
  • Nov 12, 2004
  • #57
Ok cool
 

mfp4073

Founding Member
Mar 14, 2001
387
0
38
Hells Ditch, FL
Nov 13, 2004
#58
  • Nov 13, 2004
  • #58
went from 3.00 gears to 3.89 and cut 1.5 seconds off 1/4 mile. Of course I am still not hooking up so this could be more.
 
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