Well...... here I am back in Sparky's Corner again! Seems like I just can't beat the gremlins out of my car on this issue. My question is on the minimum needed CCA from a battery to handle the compression of a 455 on start up esp when warm (motor and ambient temperature). I THINK compression is around 9:1 or maybe 9.5:1 on my engine but that's a best guess. You also have to factor in that I am located in the Deep South where temps recently have been 95 degrees with 60% humidity. I have replaced the following which is either new or less than 1-2 yrs old: battery cables (Beldon 2 gauge HD units), voltage reg (Wells), alternator, ignition system (MSD 6A), etc. Diagnostic check yesterday revealed all good except for a marginal battery. I was running a Champion battery in a 60 series case size so that I could use my fake Battery topper cover. It is a measly 525 CCA capacity. I also have an older Autozone Platinum series batt in the car now just charged up rated at 810 CCA. AZ batt is 2-3 yrs old so we'll see how it does. How much CCA do I need? If the AZ batt fails, I plan on buying another one perhaps in the largest and most CCA I can find. May go with a yellow top Optima and use the 60 series and topper for those few shows. Does anyone know if one can get a 60 series case batt in a CCA capacity greater than 800? All help and suggestions appreciated. I'll put the other charged batt in trunk so if to jump myself or replace since this car continues to let me down. Maybe I should post in the Help from Above section for needed prayers for my car?? o No:
do u have heat shield between the starter & the exhaust manifold ? when the starter gets hot & the battery fails to turn it over u may need to purchase one of those small high torque starters . someone on this site sells them .
Yes, the factory small heat shield is present between starter and PS exhaust manifold. I've heard good things about those hi torque mini starters but just had my stock one totally rebuilt. So far today, car is starting well with well charged 810 CCA battery. If I were to replace the battery, what do you guys think as to a powerful CCA conventional battery vs a yellow top Optima? I have a red top Optima in my TR but it's only a couple months old so no real track record here personally. I believe the yellow top one is more powerful. If it matters, car isn't driven real regular and sometimes may sit for a couple of weeks before driven.
A rule of thumb used in the past, for the non computer cars was to use one CCA/cI displacement. Your 810 CCA battery shoudl work fine. If you still encounter problems, it might be wiese to check the usual suspects, such as charging problems, or the stray drain. You might also try using slightly larger cables, as connections and connectors usually corrode w/age. Ray
