Whew!..ok..got a bike with gears..10 speed, mountain. Get on it then shift the gears so that the chain is on the small gear up front and a big gear in the back. This would be a low gear to a car or truck 4.11,4.86,5.13 . Then do the opposite big in front, little in back this is a high gear 2.76,3.08. Hopefully you are able to draw your own conclusions on gear ratios... by the way do you have a hot sister?

 

67 fury, excelent job on the explanation. I worked in a bike shop for 9 years so I guess that the gear ratio thing makes complete sense to me.

 

Ok guy's you really have me confused now. I have a Hemi, 04, with 17 in tires, and a 3.55 rear and the towing package. It's a quad cab, 4x4. This combination is go for what. ? Tow maybe. I don't tow every day just once in a while only in the summer. It seems to get good mileage once I'm on the open road. My 95 Ford Bronco with a 5.0 never got this good of mileage on the road, only better locally. So is this a good combo ,average, what?

 

Hemi OFF Road I think I understand gear ratios just fine I submitted my calulations to illustrate RPM variation with different tire diameters and gear ratios. And to illustrate how Dodge is screwing up by not offering options that will improve performance and miledge. You can't tell me that an engine making 345 HP with gobs of low end tork would suffer a big perfomance loss with a 3:55 verses a 3:92 cog...However, it would pull a couple hundred RPM off the tach at highway speed and if you understand gear ratios and power curves you should understand that it it would also improve fuel economy. Now on the other hand if your big into towing or heavy loads the 3:92 would be better especially with the 20"s. Myself I'll take the reduced RPM at highway speed any day..better miledge and easy on the motor while still in the ideal power curve for the Hemi.

Now if I want to go fast ...I'll just get in my Chevrolet...

 

hemi dave, I do belive that a 3.55 in a hemi will decrease performance significantly. I have had plenty of experiences with the effect of gear ratios on vehicles. I am into lifted trucks and gears are very very important. A 3.92 to a 3.55 is extremely noticeable, I dont care how much power the hemi makes. I also wouldnt say that the hemi has gobs of low end torque. That isnt where the hemi is strong. Anyone that tows with a hemi will tell you that you have to rev it as it is just to stay in the torque. Peek torque does NOT mean gobs of low end torque. You made the comment of better mileage and easier on the motor, and I completely agree with you on that for a 3.55 at freeway speed. If you read my post, you would see that I am very aware of that. What you may have overlooked is that in my post I keep saying its a give and take. You give in one direction and take in another. While it may be better mpg on the freeway and lower stress on the motor on the freeway, it does just the opposite to the acceleration from stop. Like I said before, I agree that dodge should offer multiple gear ratios but a 3.55 is not one that I would reccomend.