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Discussion Starter #1
is 3.91s for a 351 4v c6 alittle excessive?
 

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I would say it depends on what you use the car for. If you travel out of town to car shows or go on cruises you might not like the 3:91 gear. My Buddy has 3:91's in his BOSS and I know he'd rather have the 3:50's mine has.
 

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I agree with the above post. My 64.5 with a mild mexican block and 5 speed runs 3.55, but I intend to change to 3.25 to get a little more highway enjoyment out of it.
 

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I have 4:10's... Just have to adjust your speed a little is all... Can't run 80-90 with everyone else...
 

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If I were to drive car much on street wouldn't go with 3:91's fine around town but if you do much hiway kinda a drag. My Boss has 3:91's and when I go on longer hiway stuff I wish was running a 3:50.

Mark
 

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Buy yourself a taller set of tires. It will bring the RPM's down, but still have the acceleration.
 

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I have 3.70's and a fmx, ok my car has 3.70's and a fmx and it turns about 3000 rpm @ 60 mph. If a OD is in your future go for it. I'd think about installing a tremec or something and have your gears. Changing your tire hieght will only change your effective gear ratio back some, no advantage.
 
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Well, again I'll be the spoiler(pun intended) I have taken my '70 Spoiler on parts of the Power Tour. It's a 4:30 Drag-Pak car. With a 25" tier I can still run 65-70... it twists a little but I still get around 17 MPG. It pays to tune the hell out of one at the strip! Car has a little over 50K on it & it loves the 4:30's... so does the loose nut behind the wheel. Ask everyone's opinion, listen to them all no matter what... & draw your own conclusion.
 

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Not really since one counteracts the other for a net effect of zero. Zero benefit and zero drawbacks
 

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It depends on your car, how you drive it and the size tire you run. If you have a 5 spd, theres no worry, but an auto or 4 spd you may only be able to drive around at 50 mph.
 
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