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Old 08-22-2019, 09:14 AM   #8 (permalink)
oil pan 4
EV convert
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Join Date: Jul 2011
Location: NewMexico (USA)
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Sub - '84 Chevy Diesel Suburban C10
90 day: 19.5 mpg (US)

camaro - '85 Chevy Camaro Z28

Riot - '03 Kia Rio POS
Team Hyundai
90 day: 30.21 mpg (US)

Bug - '01 VW Beetle GLSturbo
90 day: 26.43 mpg (US)

Sub2500 - '86 GMC Suburban C2500
90 day: 11.95 mpg (US)

Snow flake - '11 Nissan Leaf SL
90 day: 141.63 mpg (US)
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Alternator ratings tend to be optimistic.
To handle 85 amps you would need at least 6 gauge wire, to handle it continously it would need to be 4 gauge.
You will need at least 15 volts to over come wire resistance between the alt and batt if you want to run higher amps.

I have found that car alts typically have about 10 amps available for charging a battery at idle speed.
That alternator is only going to be able to make anywhere near 70 amps is spinning it 7,000rpm.
Even my modified DR44G welding alternator only makes about 25 amps at idle speed externally powering the armature with 13v. The DR44G is a pretty good size medium duty commercial truck alt.
1984 chevy suburban, custom made 6.5L diesel turbocharged with a Garrett T76 and Holset HE351VE, 22:1 compression 13psi of intercooled boost.
1989 firebird mostly stock. Aside from the 6-speed manual trans, corvette gen 5 front brakes, 1LE drive shaft, 4th Gen disc brake fbody rear end.
2011 leaf SL, white, portable 240v CHAdeMO, trailer hitch, new batt as of 2014.
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