I bought a TDI!

[Isaac Zachary]

Originally Posted by Taylor95

I'm not sure. A lot of other Jeep owners have done the TDI conversion, but they report mpg to be in the 30s. However, none of the builds were eco minded and the ZJ is already a lot more aerodynamic than other Jeeps.

I found a company that makes hybrid kits for nonhybrid cars. If I could get that, then I think 50 mpg should be easy.

50mpg! That depends on where and how you drive.
Aero isn't as important in city streets, where a hybrid design could help significantly.

On the freeway or highway a hybrid isn't going to help. Actually it could make mileage worse. But more aero would improve highway fuel mileage.

Obviously having both a hybrid and better aero would help get you the best of both worlds. Aero is the combination of frontal area (how tall and wide) and the shape (and speed, technically).

[Taylor95]

Originally Posted by Isaac Zachary

50mpg! That depends on where and how you drive.
Aero isn't as important in city streets, where a hybrid design could help significantly.

On the freeway or highway a hybrid isn't going to help. Actually it could make mileage worse. But more aero would improve highway fuel mileage.

Obviously having both a hybrid and better aero would help get you the best of both worlds. Aero is the combination of frontal area (how tall and wide) and the shape (and speed, technically).

I had a conversation with the people that are developing the hybrid conversion kits. They told me that range would still be increased a little bit even with sustained highway driving! They have a bold claim of over 100% mpg increase in combined driving.

[freebeard]

Does the kit use OEM GM eAssist altermotors, or something else?

[Ecky]

Generally speaking, a electric assist motor bolted onto a gasoline (or diesel) engine improves power, but does very little for economy, if nothing else is changed. You can recover very small amounts of energy when decelerating, and perhaps you can upshift sooner because more torque is available at lower RPM.

The addition of auto-stop helps in city driving as well, but that's harder to implement because it requires some integration between the engine's computer and the motor's computer.

On the highway, the only added benefit you may get is that a 3 phase motor and DC-DC converter may be more efficient than an alternator at creating 12v.

Those hybrid systems that help significantly in city driving typically do so by having the system highly integrated into the transmission. For instance, Toyota's HSD can toggle the gasoline engine on and off on its own while driving at a steady speed, basically doing pulse and glide without causing any speed variation. It can also keep the engine off during very low speed crawling, only firing it up to top off the battery.

The major benefit of hybrids on the highway is that they tend to incorporate much taller gearing, and smaller engines, than would otherwise be acceptable to typical drivers.

[Isaac Zachary]

Originally Posted by Taylor95

I had a conversation with the people that are developing the hybrid conversion kits. They told me that range would still be increased a little bit even with sustained highway driving! They have a bold claim of over 100% mpg increase in combined driving.

That's a pretty bold claim. Technically possible? Almost not.

My question is how does it interface? Does it replace the transmission or connect to the output shaft or or to the crank pulley on the engine or power the normally unpowered wheels?

All I know is that on the highway my Toyota hybrids have greater transmission losses than a manual transmission, but with the benefit of being continuously variable and being able to add power when more power would make the engine less efficient, or suck up some power when the less power would make the engine less efficient.

Edit: Never mind. Ecky nailed it.

[Taylor95]

Check this out: https://www.fluxhybrids.com/

They actually claim a 144% improvement. This is based on the EPA combined estimate, and they test this using similar methods as the EPA. Their first test vehicle was a Ford Ranger that saw a 100% improvement.

The kit works by mounting to the back of the transmission. They told me that the car basically thinks that it is going downhill. I was told that they are working on improvements so that the driveshaft does not have to be shortened.

[Taylor95]

Originally Posted by skyking

bummer man. On the VE engines:
Oil in the intercooler piping is normal. it gets in there and just hangs out. i put a drain on one of my beetles to dump it out the low point.
If they are stock, the ASV valve will prevent a traditional runaway engine. If you delete the EGR and install a "race pipe", then you lose that benefit.

Not a problem. I have to keep all emissions equipment for registration purposes.

[Ecky]

Originally Posted by Taylor95

Check this out: https://www.fluxhybrids.com/

They actually claim a 144% improvement. This is based on the EPA combined estimate, and they test this using similar methods as the EPA. Their first test vehicle was a Ford Ranger that saw a 100% improvement.

The kit works by mounting to the back of the transmission. They told me that the car basically thinks that it is going downhill. I was told that they are working on improvements so that the driveshaft does not have to be shortened.

I see now. It's a PHEV conversion, rather than just hybridization. The "50mpg" figure comes from grid electricity, and would probably drop down near 20 again once the vehicle needs to sustain itself on gasoline alone. Which is not to say it wouldn't still be an awesome conversion.

[Taylor95]

Originally Posted by Ecky

I see now. It's a PHEV conversion, rather than just hybridization. The "50mpg" figure comes from grid electricity, and would probably drop down near 20 again once the vehicle needs to sustain itself on gasoline alone. Which is not to say it wouldn't still be an awesome conversion.

They have both HEV and PHEV kits. I believe the 144% is for the HEV according to their website.

The PHEV kit sounds interesting but I did not get much info on that. It would have a range of 20-25 miles though.

[cRiPpLe_rOoStEr]

Originally Posted by Taylor95

I'm not sure. A lot of other Jeep owners have done the TDI conversion, but they report mpg to be in the 30s. However, none of the builds were eco minded and the ZJ is already a lot more aerodynamic than other Jeeps.

People often look at displacement as the only defining factor of how much more efficient an engine might be, yet it's not an absolute rule-of-thumb. Sometimes a noticeably larger engine revving much slower (or maybe not so much slower) may provide a similar mileage or even better than a more rev-happy small one. On a sidenote, the electronically-governed version of the Cummins ISB3.9 rated at 203hp factory-fitted to the Brazilian F-250 from late-'05 to 2011 and backed by a 5-speed ZF manual could reach around low-30s if driven by someone not too lead-footed.