3.08 Vs. 3.70....
Race Director
Joined: Jan 2000
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From: Corsicana, Tx
2020 C2 of the Year - Modified Winner
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Check this site to play with various ratios and other fun things.
http://wallaceracing.com/Calculators.htm
Unless you change trans gearing, expect a pretty big butt-o-meter difference.
JIM
http://wallaceracing.com/Calculators.htm
Unless you change trans gearing, expect a pretty big butt-o-meter difference.
JIM
Cruising
Joined: Feb 2008
Posts: 11
Likes: 0
Safety Car
Joined: Oct 2005
Posts: 3,570
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From: Algonac Michigan
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Instructor
Joined: Apr 2006
Posts: 243
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From: Canton MI
I don't have any of the math done (but others have provided simple online calculators you can use)...but a general comment from a 3.70 gear owner...the extra you get on the seat-of-the-pants meter is worth the extra revs at cruising speeds. To me, this gear is a pretty good compromise between too tall and too short.
I rarely take my car on the expressway right now (the suspension rebuild currently underway will change that, probably) but I do cruise at a steady 60 or 65 (on 2 lane highways) and the 3.70 feels just fine. The way I figure it, the sidepipes sound better at higher revs anyways, so the 3.70 keeps me in the sweet-sounding zone a lot more. If you're one that keeps track of fuel economy (which, I don't on this car...because honestly who cares? Its a hobby, I'm just happy to drive it when I can), you will definitely see a difference. For instance, as a DD, I certainly would go with a 3.08 or thereabout...maybe a 3.55.
Good luck. The calculators should help you choose a gear but I wanted to give you some experience, too.
I rarely take my car on the expressway right now (the suspension rebuild currently underway will change that, probably) but I do cruise at a steady 60 or 65 (on 2 lane highways) and the 3.70 feels just fine. The way I figure it, the sidepipes sound better at higher revs anyways, so the 3.70 keeps me in the sweet-sounding zone a lot more. If you're one that keeps track of fuel economy (which, I don't on this car...because honestly who cares? Its a hobby, I'm just happy to drive it when I can), you will definitely see a difference. For instance, as a DD, I certainly would go with a 3.08 or thereabout...maybe a 3.55.
Good luck. The calculators should help you choose a gear but I wanted to give you some experience, too.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,113
From: Crossville TN
If you are thinking of going FROM 3.73 TO 3.08 [for fuel economy and comfort at cruising speed], it will be a huge improvement. As mentioned, the car's acceleration will suffer....but, at $4 per gallon, the 'suffering' will either be in acceleration or your wallet.
Race Director
Joined: Apr 2003
Posts: 19,345
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From: Tampa, Florida
For what it costs to make the switch it'll take years to recoupe the cost of the gear change (depending on mileage driven yearly).
Safety Car
Joined: Sep 2007
Posts: 4,445
Likes: 326
From: Indy Indiana
I bought mine with 4.56 gears, One of my first big projects will be to put in 3.08's. Running 3700 RPM in the interstate for an extended time makes me fearful of wearing out a very valuable engine.. I can take it around town, but I sure don't want to take it out of state on a long cruise. What on earth was the previous owner thinking when he put in that ratio? I probably don't care about a butt-o-meter.. I just like to cruise!
Melting Slicks
Joined: Jul 2005
Posts: 2,545
Likes: 3
From: 406ci SB, AFR 180 Heads - 490 HP @5,600 RPM 529 lb-ft @ 4,100 RPM
I bought mine with 4.56 gears, One of my first big projects will be to put in 3.08's. Running 3700 RPM in the interstate for an extended time makes me fearful of wearing out a very valuable engine.. I can take it around town, but I sure don't want to take it out of state on a long cruise. What on earth was the previous owner thinking when he put in that ratio? I probably don't care about a butt-o-meter.. I just like to cruise!
Safety Car
Joined: Oct 2006
Posts: 3,930
Likes: 15
From: Calgary Alberta
