The group 27 is the larger of the series, old mopar Red cap battery. The Group 24's has yellow or green caps depending on year. I agree about the 27 filling the battery tray better but for "correctness" a 440 of that year should have a group 27 "tar top" Look into the dry gel cel batteries, they are more expensive but are unaffected by temperature and are much more durable. Aftermarket like Exide has up to 1000CCA batteries, that is whatI have for my '63 472 Hemi Polara. It's in the trunk so looking correct under the hood is not an issue, the Hemi is pretty incorrect as well, but looks good though ;-) On Mon, Jun 30, 2008 at 1:40 PM, Kevin Merkley <krmerkley@xxxxxxxxx> wrote: > > I also believe that cold cranking is what you look for in determining > the "strength" of a battery. > > The 24 vs 27 is the length of the battery. I always found that the > longer battery looked better and filled the battery tray. > -- Steve '63 Hemi Polara ---- Please address private mail -- mail of interest to only one person -- directly to that person. I.e., send parts/car transactions and negotiations as well as other personal messages only to the intended recipient, not to the Clubhouse public address. This practice will protect your privacy, reduce the total volume of mail and fine tune the content signal to Mopar topic. Thanks! '62 to '65 Mopar Clubhouse Discussion Guidelines: http://www.1962to1965mopar.ornocar.org/mletiq.html.