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RON WOODGEARD · 11-30-2004, 04:36 AM

Gears are one of the most important facters in what you want to do with your truck..

If you don't haul or pull and do a LOT of highway driving, then 307's are the way to go.. But you're going to suck at "off the line performance" Just remember tire size also has a lot to do with the final gearing to the street. Taller tires are going to give you a Higher ( lower numerically) Ratio, and short tires are going to do the opposite..

373's are a great performance gear for a Small Block.. 350's would be fine for a big block.. But basically, you have to tune the gears to your usage.. In Drag Racing, you want you Ideal RPM ( red line) to be just as you hit the traps ( end of the Quarter mile)

I have 4:10's in mine now, I put them in when my Truck was Raised 8" and I had 32" tires all the way around. Now I have 27" tires and it's lowered ( which the lowering doesn't have anything to do with Final Ratio) I live in a rural area, 35 miles from the closest little town, I'm sure I will be changing them out in the Future when I get it back on the road. But I like that Off the line snap, so I won't be putting in 307's.

One additional thing !!
You need to keep the motor you have in the working RPM that it's designed for.. And here's where some work can come in... figuring what RPM at what speed you'll get the best gas Mileage at.. I've always done this with a Vaccuum guage..

11-30-2004, 04:36 AM	#48
RON WOODGEARD Resident Young Old Dude ! Join Date: Jul 2001 Location: Nevada Posts: 1,948	Gears are one of the most important facters in what you want to do with your truck.. If you don't haul or pull and do a LOT of highway driving, then 307's are the way to go.. But you're going to suck at "off the line performance" Just remember tire size also has a lot to do with the final gearing to the street. Taller tires are going to give you a Higher ( lower numerically) Ratio, and short tires are going to do the opposite.. 373's are a great performance gear for a Small Block.. 350's would be fine for a big block.. But basically, you have to tune the gears to your usage.. In Drag Racing, you want you Ideal RPM ( red line) to be just as you hit the traps ( end of the Quarter mile) I have 4:10's in mine now, I put them in when my Truck was Raised 8" and I had 32" tires all the way around. Now I have 27" tires and it's lowered ( which the lowering doesn't have anything to do with Final Ratio) I live in a rural area, 35 miles from the closest little town, I'm sure I will be changing them out in the Future when I get it back on the road. But I like that Off the line snap, so I won't be putting in 307's. One additional thing !! You need to keep the motor you have in the working RPM that it's designed for.. And here's where some work can come in... figuring what RPM at what speed you'll get the best gas Mileage at.. I've always done this with a Vaccuum guage.. Last edited by RON WOODGEARD; 11-30-2004 at 04:40 AM.