My 2F to 1HZ-T swap thread

[60/40GUY]

Kevin,

Great info to have. Thanks

Sounds like I'll be using the 4:11's

Thanks again. This is a great thread with a lot of usefull information.

Frank

[kevinmrowland]

Update:
Still love the new engine.
The 4.11s have been back in for awhile now, thankfully, the 3.7s were starting to really kill me. I have only been on one trip since then, 857 miles, two states, a variety of terrain including flat highway, hilly highway and dirt back roads in VT.
Three tanks of gas at:
17.15mpg
18.97mpg
19.19mpg

18.4mpg overall average.
This is compared to the, boring to drive, 3.7 gears that netted me 18.5mpg. All I did was back off the skinny pedal a bit and I got the same mileage out of the 4.11s as I did with the 3.7s but still had fun driving. No unnecessary hot rodding or quick starts, 70mph for 8+ hours on the highway, everything else was back roads, still had power to spare on the hills. Amazing the difference gearing makes.

[Dougal]

Originally Posted by kevinmrowland

Update:
Still love the new engine.
The 4.11s have been back in for awhile now, thankfully, the 3.7s were starting to really kill me. I have only been on one trip since then, 857 miles, two states, a variety of terrain including flat highway, hilly highway and dirt back roads in VT.
Three tanks of gas at:
17.15mpg
18.97mpg
19.19mpg

18.4mpg overall average.
This is compared to the, boring to drive, 3.7 gears that netted me 18.5mpg. All I did was back off the skinny pedal a bit and I got the same mileage out of the 4.11s as I did with the 3.7s but still had fun driving. No unnecessary hot rodding or quick starts, 70mph for 8+ hours on the highway, everything else was back roads, still had power to spare on the hills. Amazing the difference gearing makes.

So for those too lazy to do the maths, what was your crusing rpm then and now?

[kevinmrowland]

Originally Posted by kevinmrowland

Currently with the 4.11s, 55mph=2000rpm, 65-2400, 75-2800.

And the 3.7s basically lowered everything about 200rpm (of course it was a percentage, not even across the band, I have it written down somewhere) but the torque was just not there anymore which is what I think killed the mileage. While the lower rpms are more efficient, it does not do much good if the engine has to work harder to compensate for less available torque.

[Bryan062087]

Have your fuel economy #'s improved any from 19 mpg?

[kevinmrowland]

?from yesterday?
I haven't even driven since the last post.

[Bryan062087]

Ahh, didn't see the date.

[Ducks]

The peak torque of the 1HZ is supposed to be 2200 rpms. I don't know how the turbo would change that. Would you be getting your best fuel mileage if you were cruising at that rpm? I know with my 2F, I get my best gas mileage when I'm cruising at 1800 - 2000 rpms. The peak torque of the 2F is 1800 rpms.

Thanks for all the work you did on putting this thread together. It is extremely helpful.

Chad

[kevinmrowland]

It is hard to explain, that peak torque was the reason I tried the 3.7s in the first place, but it seems to be negated by how the different gear set equals less torque at the wheels, so in essence, even thought the cruising rpms were right where they should be, getting to those speeds took more energy since some of the torque was lost in the gears.
This is not based on any prevailing scientific principle other than how it felt to drive. The long and the short of it is that the 4.11s are WAY more fun to drive, and if I back off the skinny pedal a bit, I can get the same mileage that the, not fun at all to drive, 3.7s afforded. So I think it is a win, win.
Now if I could find a nice 6 speed to bolt behind the HZ.............