Duke's Garage: Electric Car Conversion Shop

I'm talking today with Dave Altschuler from Duke's Garage in Westminster, CO. Duke's Garage is an electric car conversion shop, but my favorite thing they've been doing lately is...well, electric, yes, but not a conversion at all. It's a brand new electric 1957 Porsche Speedster with an AC electric motor system and lithium iron phosphate batteries.

Interview with Dave Altschuler

Lynne: What is this beautiful thing you've been building, Dave? It's not a conversion, exactly, is it...it's a fiberglass replica, and it looks new. Where do you get those, and how much do they cost?

dukes garage blue speedster

Dave: Duke's Garage is the western U.S. distributor for the Beck Speedster and 550 Spyders, which are high-end replicas of the 1957 Porsche 356a and the 1955 Porsche 550 Spyder. We assemble the brand new vehicle with an electric drive train, so its not really a conversion because it never had a gas motor. The cost for this 'eSpeedster' starts at $55K.

Duke's E-Speedster Video

So you'll do all that electric conversion for me, right? I don't have to do any of it myself?


You got the motor from HPEVS? Did you order it straight from them? Did you get the controller from them, too, or did you order that separately?

We're also a dealer for Hi Performance Electric Vehicle Systems, and use their AC-50 motor and controller kit in the eSpeedster as well as in other light vehicle conversions.

dukes garage pickup

The batteries are not a type of LiFePO4 that I recognize. I know CALB and Thundersky. What is Voltronix, and where can I get those? How does the cost compare to the others?

Voltronix batteries are owned by Flux Power and are used in their battery modules. Duke's Garage is also a dealer for Flux Power. The cost is comparable to other prismatic large format lithium iron phosphate cells, but Voltronix batteries undergo more extensive quality assurance and testing procedures.

Duke's E-Speedster Video Update

How long has your eSpeedster been on the road now? Is the motor/controller still holding up well?

We have built two eSpeedsters with the same configuration and each of them has been road tested extensively. The first one was completed May 2010. The motor and controller are solid; this has proven to be one of the most well designed yet inexpensive drive systems on the market for electric vehicle conversions.

How is the controller cooled?

dukes garage bug

We have developed a water-cooling system for the motor controller which enhances performance and prolongs run-time indefinitely for long range driving.

You've got 100 mph and 110 miles listed on the EV Photo Album page for speed and range. Can you give me an idea of how the range fluctuates with freeway driving vs. in-town driving?

Freeway driving will reduce range by approximately 25% due to air drag and limited use of regenerative braking.

The HiPer AC system is so much less expensive than the AC drive systems I'm used to seeing. Have you done both types of conversions, and can you compare the two?

dukes garage red speedster

We have not used any other AC drive systems, but the more expensive ones are capable of higher peak and continuous horsepower. This makes them more suitable for larger vehicles and will allow for better acceleration, especially on hills. However, at half to a third of the price, the HPEVS kit makes AC electric vehicle conversions accessible to a wider range of people.

You also asked about conversions on larger vehicles...I usually recommend smaller vehicles, but there is no reason that you couldn't convert larger ones like a 57 Chevy or a 3-ton pickup. There are some motors on the market that are powerful enough to move these vehicles, and if that's what it takes for someone to put another EV on the road, it makes it worthwhile.

Thank you, Dave.

Contact Duke's Garage

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