Pondering a Differential Gear Change
Posted: Tue Oct 13, 2020 1:14 pm
I've been kicking around the idea of an eventual differential gear change from 3:23's to 2.78's or something along that line on my 385 HP ZZ4 trike for the sake of picking up 2 or 3 extra MPG's on the freeway, if I can net that much? Hard to say. The RPM difference would be around 400-500 at 70 MPH, which isn't really a whole lot. Of course, the gap would widen at 75 MPH, which is the limit on most of our state's major routes.
Moving in the opposite direction, my Mustang lost 4 MPG freeway when I went from 2.78's to 3.55's. Dropping from 31 to 27 MPG was not that big of a hit in exchange for quicker acceleration, especially since I gained city MPG's due to the ability to skip-shift to higher gears around town, so it evened out pretty well.
Back to the trike: I don't know if a gear swap would really gain a similar difference as the Mustang lost, unless maybe I go to 2.50's like my brother did on his 350 HP LT1 Corvette? Even so, with only an 8.5 gallon main tank and a 3.5 gallon auxiliary, I might get an extra 30 miles (?) per fill-up between the two? That's not a whole lot, but the desert southwest can be a scary place on a gas guzzler. I always carry extra just in case, because some of the more remote fuel stops (historic Route 66 and old highway 80 in AZ) are seat-of-the-pants. I've been there on the Hoss; I know! BUT...I made it back, so it's not like it's a dire situation. I'm just not sure a gear swap would be worth it, though it would be a world easier than a TH350 to 700R4 swap, at least at this point where my means are concerned. I love the open road, but man, I hate literally not being able to pass up any gas stations in the desert southwest!
Moving in the opposite direction, my Mustang lost 4 MPG freeway when I went from 2.78's to 3.55's. Dropping from 31 to 27 MPG was not that big of a hit in exchange for quicker acceleration, especially since I gained city MPG's due to the ability to skip-shift to higher gears around town, so it evened out pretty well.
Back to the trike: I don't know if a gear swap would really gain a similar difference as the Mustang lost, unless maybe I go to 2.50's like my brother did on his 350 HP LT1 Corvette? Even so, with only an 8.5 gallon main tank and a 3.5 gallon auxiliary, I might get an extra 30 miles (?) per fill-up between the two? That's not a whole lot, but the desert southwest can be a scary place on a gas guzzler. I always carry extra just in case, because some of the more remote fuel stops (historic Route 66 and old highway 80 in AZ) are seat-of-the-pants. I've been there on the Hoss; I know! BUT...I made it back, so it's not like it's a dire situation. I'm just not sure a gear swap would be worth it, though it would be a world easier than a TH350 to 700R4 swap, at least at this point where my means are concerned. I love the open road, but man, I hate literally not being able to pass up any gas stations in the desert southwest!