Factory installed battery

[bc3j]

I have a 70 Challenger R/T 383 N code with air built in the LA plant without a build sheet available. If I am reading the FSM correctly, a special equipment car (heavy duty or air) should have the 70 amp battery.  Can I correctly assume that a group 27 battery would have been factory installed? I believe the group 27 was the red cap battery.  Thanks for your input.

[Cuda Cody]

I thought it would have been a yellow cap battery? 

Do you have AC?

[anlauto]

I've recently restored two 1970 383 Challenger RT's both with factory AC. Both cars came with their original broadcast sheets and both of those cars called for Group 24 yellow cap batteries ....both were also loaded with power options, windows, sunroofs etc...

[6bblgt]

yes, the group 27 (F25 70amp) red cap battery was a $12.95 OPTION on a '70 Challenger (SE & R/T included)

it was included on R/T with any of the up-grade engine OPTIONS 440 HP, 440 Six Pack & HEMI

it is particularly "RARE" ~2.9% installation rate (US shipped cars).  around 535 R/Ts with 383 (most are found in cold weather states where dealers knew the battery was important in winter)

the battery STARTS the car, the alternator keeps the battery charged and the car's accessories operational

(price change in line 1)

[Floyd]

I know your talking 70s, but I have a 71 340 Challenger coded for a Group 27.  It's a Wisconsin car and also has the rear window defroster.  I have wondered if the battery was part of an option package or just ordered?

[RUNCHARGER]

I thought 27's came with A/C, perhaps that started in the early 70's though. I know my dealer ordered 27's in cars with big blocks along with a block heater in everything. People would buy 500 miles south in Vancouver to save $200 and then phone the dealer when their car wouldn't start in the winter.

[anlauto]

Well I have two buildsheets from 383's with AC and both came with 24 batteries

[Cuda_mark]

Why would the higher amp battery be included with the performance engines? The compression ratio?

[js27]

Why would the higher amp battery be included with the performance engines? The compression ratio?

I would say YES-the higher Compression and larger cubic in. would have more resistance to turn over and a bigger strain on the starter and drag on the battery.
JS27

[headejm]

For what it's worth...my 1970 R/T SE 383 w/ AC came with a Group 24 yellow cap battery. I believe the yellow cap battery is the standard battery for my setup. 

[6bblgt]

yes, the 440s & HEMIs received the larger capacity battery because they are bigger, have more compression and are harder to START

the R/T battery numbers above are for US shipped cars, WI gets cold in winter & most of CANADA so I'd expect big-battery smaller than HEMI/440 engine cars to be more common there

ordering A/C included the 50amp alternator (VS. the STANDARD 37amp unit) NOT the bigger battery

my 383 R/T with over $1,300 worth of OPTIONS including A/C is coded for the group 24 battery

[6bblgt]

here's an invoice for a simple 318, 3-speed manual transmission Barracuda
F25 (group 27 battery) & D91 (sure-grip) ordered thru a Wisconsin dealer in December    think cold weather & snow had something to do with it?

[bc3j]

Thank's everyone. I wasn't sure with no broadcast sheet. The car is an A/C car and I currently have a yellow capped battery in it but wasn't sure if that was correct. I guess I interpreted the FSM incorrectly.

[7E-Bodies]

Looks like mine was one...learn something new here every day.

[benlavigne]

Mine's a true Canadian car, F25 battery, N25 block heater, but strangely enough, no rear defog... Must have been cheaper to get it dealer-installed, which could make sense as it was ordered as a demo...
@6bblgt , any info on percentages for JH23 also?
Ben