Porsche Boxster Black EcoMax

[Arragonis]

Originally Posted by skyl4rk

TDI and gear it extremely high.

My initial thought about not recommending this approach would be that most VWs are transverse and the Boxster is inline - however of course the Passat and Audi models are inline (except the A1,2,3).

[nimblemotors]

This is a consideration.
A conversion to all-EV would eliminate any CARB issues.
Or a swap using the complete Prius drivetrain maintaining its ODBII.
From this standpoint, it would be best to convert to all-EV or all-Prius to register the car in California, and modify it afterward to avoid the smog police.

Or register it in Mexico

"Tourists from countries who are party to the Geneva Convention and the Regulation of Inter-American Motor Vehicle Traffic can also legally drive their own private cars bearing valid license plates/registration tags issued in their native country for a period not to exceed one year from their date of arrival."

Originally Posted by mwebb

how do you expect
do get by CARB .

if you do the modification , won't CARB deny a registration and inspection based on
"tampering" with an existing OBD2 platform ?

[YukonCornelius]

Originally Posted by mwebb

how do you expect
do get by CARB .

if you do the modification , won't CARB deny a registration and inspection based on
"tampering" with an existing OBD2 platform ?

He could register it at a family address in another state and be worry free. My friend in CA has been doing this with his modded Evo for 5 years.

[lowglider]

A mid-engined Porsche with max mpg, what a brilliant idea!

A rotary engine would really be perfect for short bursts of power, but if you would want to go for power along with big mpg and range I would advise building an all EV drivetrain with a lightweight ICE used only for charging the batteries. This way:
1. The ICE can run (when needed for range) at its max efficiency for powering the batteries and thus increases mpg
2. the maximum burst of power is not limited by the ICE
3. a lot of weight is saved because there is no need for ICE drivetrain

[nimblemotors]

Originally Posted by lowglider

A mid-engined Porsche with max mpg, what a brilliant idea!

Thanks, it was Mike Donlon's fault..

A rotary engine would really be perfect for short bursts of power, but if you would want to go for power along with big mpg and range I would advise building an all EV drivetrain with a lightweight ICE used only for charging the batteries. This way:
1. The ICE can run (when needed for range) at its max efficiency for powering the batteries and thus increases mpg
2. the maximum burst of power is not limited by the ICE
3. a lot of weight is saved because there is no need for ICE drivetrain

Yeah, I think this is what I'm thinking, and is mostly how the Prius drivetrain already works, except its battery power is very limited, as well as its ICE. The prius can run the ICE to recharge the battery independent of the cars movement so it can run at max efficiency, and does when you need more power (like going up hills or full acceleration) but it also contributes to moing the car.

If you have the ICE, might as well have it contribute its power so its not dead weight when you accelerate, at least when you want max power for racing or showing off, not necesarily from every stoplight, if we have a plug-in hybrid, it could not use the ICE at all unless you ask it to.

So the question is how to get the Prius to have more battery power, and/or how to get more power from the ICE.
Just changing the 1.5L to something that is a more normal engine with low-rpm torque would make the car a lot faster. The Rotary would be a good physical fit in this car with the Prius transaxle.
However, if I can get more electrical power I could use a smaller a 3-cyl Suzuki motor for the ICE. I have a few of those already, and can tweak it to output more.

[Nevyn]

Put a turbo on a Prius engine? It takes a fair bit of work (from the one thing I read), but it's doable.

[UFO]

With a rotary, you will not have an improvement in fuel efficiency. The rotary has excellent power to weight, but terrible economy.

By the way, nice find. Boxsters may not be fast, but they handle well and look good.

[nimblemotors]

Driving on electrical power will more than make-up for it and the weight reduction is important to maximize that. Go fast or take a long trip on all gas, and yes it will not get 50mpg with the rotary, like the Prius.

2.5L Boxster gets 27mpg on the highway.
The RX7 gets 25mpg on the highway.

Originally Posted by UFO

With a rotary, you will not have an improvement in fuel efficiency. The rotary has excellent power to weight, but terrible economy.

By the way, nice find. Boxsters may not be fast, but they handle well and look good.

[Jim-Bob]

For an engine, the Prius uses an engine that is in the same family as that used by the Yaris and the original Scion XA/XB (albeit with a camshaft grind intended to give it Atkinson cycle characteristics). The European Yaris is available with a larger 1.8 liter engine too, which could be an option if you could source one. There are also supercharger and turbocharger kits for the Yaris and Prius engines from companies like TRD and all the typical Japanese tuner companies. I do however think that you will have a lot of difficulty fitting any of these engines to a Boxter because the original engine was flat. Plus, there is no topside engine access and the factory required everything to be serviced from underneath. If memory serves, above the engine is a cargo space that could be converted into an engine bay if you went through with the swap. It could also be used for batteries in the case of a pure EV, but it would likely throw off the center of gravity, weight distribution and handling.

[some_other_dave]

Originally Posted by lowglider

A mid-engined Porsche with max mpg, what a brilliant idea!

I think that idea has been done before.... Otmar's 914 Electric


...Oh, and there is access to the top of the Box engine. There is a panel up under where the top stows that is removed for access to the top side of the engine.

I'm still wondering about the height requirements. If the Prius drivetrain is short enough, it would leave some significant space in front of the drivetrain for more batteries.

-soD