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Should I Change Gears

  • Thread starter Thread starter vmurh
  • Start date Start date Jun 30, 2004
V

vmurh

New Member
May 26, 2004
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Jun 30, 2004
#1
  • Jun 30, 2004
  • #1
Hello, I am new to this board. I have a beautiful 91lx 5.0. I do not race just get out and cruise around on the weekend. The car is automatic with 2.73 rear end. Would like the car to feel a little more spunky. Would 3.27 gears be a noticable difference?

Also. what about underdrive pulleys on just the crank and water pump? I do not think I would want to slow down the alternator.
 

5ive.oh

Founding Member
Feb 23, 2001
195
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0
Rocky Mountain House, AB
Jun 30, 2004
#2
  • Jun 30, 2004
  • #2
Welcome to the board, there are a lot of people here that are fountains of knowledge. In my research for gears most people recommend 4.10's for auto's, but if you want to maintain good hiway driving I would suggest 3.55's and yes gears are prolly the best seat of your pants mod you can do.
 
8

85GTlover

New Member
Mar 20, 2004
704
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0
Jun 30, 2004
#3
  • Jun 30, 2004
  • #3
Go for 3.73 gears over those and the pullies are a very good idea to, some might say it defeats the purpose to not change the alt pulley too but some peple do just that. You would be better getting a 3G 140 amp alt to help with charging, but your idea would help that problem. An electric fan is a good idea too. Another thing is welded strut frames.....get them, you want and your car needs them.
 

timewarped1972

Member
Jun 17, 2004
642
0
16
mesa, az
Jun 30, 2004
#4
  • Jun 30, 2004
  • #4
welcome to the board. i'm somewhat new here myself, and so i'll tell you before someone else does try the search feature when you have a question then post, reason being, gears are one of the most talked about, and debated posts on here and i aint hardly kidding......lol.........
i myself have a similar car ( see my sig ) and as far as i know alot of automatics came with 3.27 gears in them.......maybe yours does have 2.73's, check and make sure. either way, 2.73 or 3.27's suck........you have a tall first gear, and with your 4th gear overdrive you'll definatly want either 3.73's or 4.10's. you'll get a bunch of people telling you 4.10 and a bunch telling you 3.73, the choice is yours ofcourse and both groups have their good arguments over which gears.
i recently did 3.73's in mine, you notice a good difference yet they are not at all a problem ( you still turn low rpms on the high way and you really dont know their in there untill you stab it ). so for a no brainer choice, 3.73's are good all around. the 4.10's are also good, many recomend them especially for automatics, you'll have more rpm on the high way, and sometimes your engine will run out of breath because the gears spin the engine faster ( if your engine is stock and you'll keep it stock ) however, if you got 4.10's and they seemed to much you could a;ways get a wider and taller tire in the rear and help compensate for that. you won't ruin your car either way, 3.73's are just more conservative....but you'll definatly want 3.73 or 4.10...............anything less would be a waste of money or pointless, especially in an automatic with overdrive. mine had 3.27's in it when i got it and that wasn't even enough......
as for pulleys, lots of people run them, but with a stock alternator they can cause problems at idle with the charging system ( it has problems stock if you ask me, lol ) and it can also slow your water pump down enough to cause heating issues at idle depending on if you live in a hot climate or not and how big of radiator you run. underdrive pulleys can also cause your a/c to not work as well at idle in traffic........so for all these reasons, and me living in arizona, i don't run them personally, but if none of those things are an issue for you then yes they work.
 

5ive.oh

Founding Member
Feb 23, 2001
195
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0
Rocky Mountain House, AB
Jun 30, 2004
#5
  • Jun 30, 2004
  • #5
I have 3.73's and in fifth on the hiway @ 100KM/H my RPM's sit at 2100. It's real hard on fuel.
 
8

85GTlover

New Member
Mar 20, 2004
704
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0
Jun 30, 2004
#6
  • Jun 30, 2004
  • #6
5ive.oh said:
I have 3.73's and in fifth on the hiway @ 100KM/H my RPM's sit at 2100. It's real hard on fuel.
Click to expand...



What is a good cruising rpm? I don't think 2100rpm is spinning too much is it?
 

5ive.oh

Founding Member
Feb 23, 2001
195
0
0
Rocky Mountain House, AB
Jun 30, 2004
#7
  • Jun 30, 2004
  • #7
I guess I'm used to my old 87 AOD with stock 2.73's that cruised @ 1700 or so down the hiway. Maybe I am more fuel concerned due to the high gas prices as well My car will run better when I get the engine to stop guzzling oil too
 
M

Matts89LX5.0

Founding Member
Nov 1, 2002
1,314
0
36
Long Island, NY
Jun 30, 2004
#8
  • Jun 30, 2004
  • #8
if you just want a little "spunk" go with some 3.55s, you can't really go wrong with gears for an auto. They need all the help they can get to wake up lol.
 
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