Which Optima Red Top?
#1
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First off yes I searched, but I haven't found an answer to this yet.
Optima Recommends its 75/25 (part number 9022-091) when you select by application. Autozone and Summit are both recommending the same unit by the specs (910CA/720CCA, 90 minute reserve)
However...
When looking at our board sponsors, it appears Thunder Racing is recommending a different spec battery, as is WS6Store, both of which are 800CCA with 120 minute reserve.
![Engarde](https://ls1tech.com/forums/images/smilies3/engarde.gif)
Any ideas why the descrepancy? As I comtemplate heads and cam later on, a higher amperage battery would be a plus for starting a higher SCR engine.
Thanks in advance!
Optima Recommends its 75/25 (part number 9022-091) when you select by application. Autozone and Summit are both recommending the same unit by the specs (910CA/720CCA, 90 minute reserve)
However...
When looking at our board sponsors, it appears Thunder Racing is recommending a different spec battery, as is WS6Store, both of which are 800CCA with 120 minute reserve.
![Engarde](https://ls1tech.com/forums/images/smilies3/engarde.gif)
Any ideas why the descrepancy? As I comtemplate heads and cam later on, a higher amperage battery would be a plus for starting a higher SCR engine.
Thanks in advance!
#5
Kleeborp the Moderator™
iTrader: (11)
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I had a 75/35 in mine (I'm not sure how it is different from the 75/25), but the other one that will fit with a little modification is the 34/78. The latter is a larger battery, and you'll have to grind a little off the battery tray to get it to fit, and it'll be very close to the A/C hard line.
#6
TECH Fanatic
iTrader: (1)
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it won't matter, buy whichever one fits best and is cheapest.
I didn't bother to lookup the actual specs for both batteries, it is very possible is it a misprint on the CCA number or battery model number. If true thought that little bit of difference in CCA you will never notice nor need for starting the car.
The reserve capacity is how long you want to run off the battery without the engine running- how long the battery can constantly output 20 or 25 amps before being dead. It most likely will not apply, unless you want to park your car at night with headlights and radio on, engine off, and play basketball and you're game lasts more than an hour then you might need the 120 minute reserve capacity battery instead of the 90.
I didn't bother to lookup the actual specs for both batteries, it is very possible is it a misprint on the CCA number or battery model number. If true thought that little bit of difference in CCA you will never notice nor need for starting the car.
The reserve capacity is how long you want to run off the battery without the engine running- how long the battery can constantly output 20 or 25 amps before being dead. It most likely will not apply, unless you want to park your car at night with headlights and radio on, engine off, and play basketball and you're game lasts more than an hour then you might need the 120 minute reserve capacity battery instead of the 90.
#7
TECH Senior Member
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Not sure but after looking at all the pics (if they're accurate) the 75/35 and 74/25 difference might just be the location of the side terminals - mine are on the outside like stock. Helms says we take a 690 CCA.