# Lead System with Boost Battery - 2009 E4

**URL:** <https://community.electricforum.com/t/lead-system-with-boost-battery-2009-e4/13979>\
**Category:** GEM Forum\
**Created:** [June 28, 2018, 1:47pm UTC](https://community.electricforum.com/t/lead-system-with-boost-battery-2009-e4/13979 "2018-06-28T13:47:50Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![rgeorge](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/rgeorge/32/2412_2.png) [@rgeorge](https://community.electricforum.com/u/rgeorge)\
**Post date:** [June 28, 2018, 1:47pm UTC](https://community.electricforum.com/t/lead-system-with-boost-battery-2009-e4/13979/1 "2018-06-28T13:47:51Z")

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Starting a new topic to document outcome with Lead Boost battery on all lead system… Any words of wisdom before I start… Dave has been a great help so far…

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**Author:** ![Inwo](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/inwo/32/1067_2.png) [@Inwo](https://community.electricforum.com/u/Inwo)\
**Post date:** [June 28, 2018, 3:49pm UTC](https://community.electricforum.com/t/lead-system-with-boost-battery-2009-e4/13979/2 "2018-06-28T15:49:35Z")

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I can’t wait. 🙂

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**Author:** ![rgeorge](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/rgeorge/32/2412_2.png) [@rgeorge](https://community.electricforum.com/u/rgeorge)\
**Post date:** [June 29, 2018, 9:07pm UTC](https://community.electricforum.com/t/lead-system-with-boost-battery-2009-e4/13979/3 "2018-06-29T21:07:39Z")

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I have disconnected the batteries from the controller and placed an additional lead battery in between the controller and b+ form the batteries… Total voltage was near 82 v. Test drove car and noticed slightly more torque however an increase in speed of 1-2 mph… I have Dave’s MM installed at its default setting, controller is defaulted. I was expecting a better increase in top speed, however batteries were about 80%. I am charging the car and the add on battery separately and will retest. I am a little disappointed with initial results.

Factory Motor/Controller

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**Author:** ![Mr.Vern](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/mr.vern/32/2658_2.png) [@Mr.Vern](https://community.electricforum.com/u/Mr.Vern)\
**Post date:** [June 29, 2018, 9:41pm UTC](https://community.electricforum.com/t/lead-system-with-boost-battery-2009-e4/13979/4 "2018-06-29T21:41:13Z")

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If you haven’t done the field weakening yet, don’t get too discouraged. I removed my speed limiter and didn’t see a big jump in speed until I weakened the field.

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**Author:** ![Inwo](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/inwo/32/1067_2.png) [@Inwo](https://community.electricforum.com/u/Inwo)\
**Post date:** [June 29, 2018, 10:27pm UTC](https://community.electricforum.com/t/lead-system-with-boost-battery-2009-e4/13979/5 "2018-06-29T22:27:30Z")

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That is disappointing, but not totally unexpected.  
Stock voltage can be 86v after a full charge. And unlike lithium you are gaining weight.  
It was worth a shot to get a performance boost for $100.  
We run up to 98v with lithium, that’s almost two more batteries worth of voltage.

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**Author:** ![rgeorge](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.electricforum.com/rgeorge/32/2412_2.png) [@rgeorge](https://community.electricforum.com/u/rgeorge)\
**Post date:** [June 29, 2018, 10:34pm UTC](https://community.electricforum.com/t/lead-system-with-boost-battery-2009-e4/13979/6 "2018-06-29T22:34:43Z")

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I will try with two batteries full charged Monday.