One
Well-known member
Im will have to go look. I have as of yet not been under it.[P[P
Taller gears
- Thread starter One
- Start date
Help Support Rat Rods Rule:
Im will have to go look. I have as of yet not been under it.[P[P
One
Well-known member
Ill try but my camera aint all that great so they might not come out very well.[P[P
One
Well-known member
I was told that my rear end was 2.79.I guess I will just stick with that.[cl[cl
One
Well-known member
I found out that its from a 70 Mavrick.
Torch
Extremely dangerous with a torch!!!
- Joined
- Jul 18, 2008
- Messages
- 1,627
I'm running a 3.22 14 bolt in my 86 chevy dually and 235 85 r 16's. I went from a 4.11 which is a 20% change.
My interstate gas mileage empty with the 350 improved 20% from 10 to 12
it still tows well but I pull it down to 1st and manually upshift when loaded heavy. I hauled a 76 f250 supercab up from tulsa on a tow dolly.
I burned 12 gallons from Omaha to Topeka(hilly), 8.5 gallons from topeka to tulsa (flat)
coming back I burned 40 gallons from Tulsa to Topeka and another 40 from Topeka to Omaha... about 6mpg? ouch
I had a 1 ton ford van 460 4x4 with 3.73 gears that got 9-10 empty and 8.5 towing another truck behind so a big engine does not necessarily mean more gas.
I have a pontiac 400 I'm going to swap into the dually. It should actually do better than the 350.
I used to get 18-20 mpg out of a pontiac grand prix with 2.73 gears and a 400/th400 on the highway and it would beat any stock 80's or 90's 5.0 ho mustang in a street race
one thing you CAN do with highway gears is downshift into 2nd at 55 and dissappear.
the only difference I've noticed between 4.11's and 2.73's is witin the first 50 feet from a dead stop otherwise there isn't much "fastness" difference if you get the rpm's out of the rear end gears or out of the way you shift it.
I generally like to have the bottom rpm of my powerband matched to about 55-60 mph which is perfect for downshifting while passing.
power=fuel so I don't like to cruise in the power band but loading an engine down won't get good mileage either like with my mileage going from 12 to 6 while loaded. it all depends on the motor how you built it, stroke, etc and if the motor has enough power at the speed you need it to run at to pull the load without enriching the fuel by low vacuum tripping the power valve open
My interstate gas mileage empty with the 350 improved 20% from 10 to 12
it still tows well but I pull it down to 1st and manually upshift when loaded heavy. I hauled a 76 f250 supercab up from tulsa on a tow dolly.
I burned 12 gallons from Omaha to Topeka(hilly), 8.5 gallons from topeka to tulsa (flat)
coming back I burned 40 gallons from Tulsa to Topeka and another 40 from Topeka to Omaha... about 6mpg? ouch
I had a 1 ton ford van 460 4x4 with 3.73 gears that got 9-10 empty and 8.5 towing another truck behind so a big engine does not necessarily mean more gas.
I have a pontiac 400 I'm going to swap into the dually. It should actually do better than the 350.
I used to get 18-20 mpg out of a pontiac grand prix with 2.73 gears and a 400/th400 on the highway and it would beat any stock 80's or 90's 5.0 ho mustang in a street race
one thing you CAN do with highway gears is downshift into 2nd at 55 and dissappear.
the only difference I've noticed between 4.11's and 2.73's is witin the first 50 feet from a dead stop otherwise there isn't much "fastness" difference if you get the rpm's out of the rear end gears or out of the way you shift it.
I generally like to have the bottom rpm of my powerband matched to about 55-60 mph which is perfect for downshifting while passing.
power=fuel so I don't like to cruise in the power band but loading an engine down won't get good mileage either like with my mileage going from 12 to 6 while loaded. it all depends on the motor how you built it, stroke, etc and if the motor has enough power at the speed you need it to run at to pull the load without enriching the fuel by low vacuum tripping the power valve open
blurooster
Well-known member
Yes you can get better gears for "take off" I have found up to 3.40:1 in junk yards(factory went to 4.11) Aftermarket make all kinds of crazy stuff for 8"
