Planning a 1999 Chevy Step van hybrid conversion.
 

hello everyone,
I am new to this forum and I have been researching a way to build a DIY gas/electric hybrid out of an 18 ft chevy step van. I am having some trouble finding comprehensive information about doing a hybrid conversion.
I would like to use the existing motor if possible and supplement it with an electric motor. Unless it would be more efficient to use a gas generator (possibly the the current engine?) to then power an electric engine?

A quick run down, its 18 ft, 5.7 L V-8 engine. 14,000 lbs all aluminum workhorse chassis. My goal, however ambitious, is to get around 40-50 mpg. Ill try about anything to do this.

Any help would be greatly appreciated.

With the 5.7L? Not so sure about that. Put a Warp 13" motor on the (manual) transmission, pile about 4,000 pounds of batteries underneath the floor and supplement it with a small efficient diesel generator, and you might be able to squeeze 40MPGe out of it if you grid-charged the batteries at night.

Is this local delivery (lots of stop/start) or highway driven? If you do a lot of start/stop city driving, it might then be worth it to get an AC drivetrain with regen. (In fact, Metric Mind used to sell a dual-motor AC direct-drive complete rear axle for EV or hybrid buses and trucks. He may still be able to get those.) For highway driving, regen won't help, so go with the cheaper DC.

This seems like the best option so far. Somebody on another ev forum was promoting using the gas engine with electric supplement but I think this will be better especially in the future as battery technology increases.

I am actually converting this to an RV, very non-conventional though. All light weight materials, no excessive appliances (like a mini-fridge). Its more of a touring van for a band that I am designing to mostly lived in but in and around cities so utilities and food will be easy access.

It will mainly be doing long highway trips so regen braking might not help but I think an AC motor might be better for future upgrades and such. Does anyone know of any literature on similar conversions? Websites, books, videos, anything that might help me more with the specifics of engineering such a project?

Metric Mind's AC motors are higher voltage (thinner cables), water cooled (for continuous use) and higher RPM (less shifting.) The nice thing about a hybrid RV is that you don't need a separate generator (and a full charge could supply your house power for a week.)

For a series hybrid (diesel generator powering an electric motor), I don't think you necessarily need any special instructions. It's a standard EV conversion (motor, controller, motor adapter, potbox connected to the throttle, batteries, charger, DC/DC, vacuum pump for brakes) plus a diesel generator (either off-the-shelf feeding your regular battery charger via 220V AC, or roll-your-own.) If you can figure out how much energy your RV takes just maintaining your average freeway speed, add 25% to that and try to size your generator to produce that much.

If you want better highway mileage, you need a smaller engine, not to strap on an electric motor. The whole point of going with a hybrid is using the electric to assist in acceleration so you can use a smaller engine.

So you think a smaller diesel engine with an electric motor assist would be better than an electric motor with a diesel generator?

Also, I would like to run the generator off of vegetable and waste oil.

Also, does anyone know anything about hydraulic hybrids, what are your feelings on those?

You can do either one, though by doing a smaller diesel with electric assist, you'll need more sophisticated controls (i.e. throttle for ICE, throttle/regen for electric), and a more sophisticated transmission.

I don't know of any hydraulic hybrid components that are readily available to the consumer.

id go with electric motor with a diesel generator and isolate the generator with soundproofing and an exhaust let out and you'd have it made thats just how id do it but opinions are like butt-holes everyone has 1 but some stink worse then others goodluck