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Do high compression engines need higher cranking amps? My "friend" has a rebuilt 350 with 11:1 compression and needs a new battery. The old Diehard had 1000 ca and 850 cca. Diehard doesn't make anything like that anymore. Is it ok to go with less cranking amps or does a high performance negine need alot of amps. Thanks for any advice.
 

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When Sears had a "sears" labeled battery, I had very god luck with them, but I have never had any luck with the DieHard series though I'm sure many will have not had the same experiences. My personal favorite is Delco with a lifespan of 5-8 years in just about anything I have put them in (including one vehicle that had a 10.5 compression ratio with 180 psi in the cylinders). Champion also makes a very good battery from everything I have read, an friends have experienced. Motorcraft....good for about 3-5 years.

But yes, a good quantity of reserve cranking power is what I look for, I prefer at least 600. Yes high CR engines do require more CCR's because the draw is greater but what your friend has is more than adequate in terms of ratings. What can also help very much is to put a switch that cuts off the ignition so that you can spin the engine with the starter first, then give spark second which reduces the load on the starter since the engine is not firing...
 

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If everything is right, he should do fine with a CCA in the 700-800 range...Sometimes adding a gear reduction starter to a high CR engine can help, as can spinning up the engine before hitting the ignition (an old trick I used when running a crank trigger on the race car)

I use marine starting batteries in the race car and it still has a stock starter and runs about 12.5:1 CR and a fairly small cam so cranking pressures are pretty high. The marine batteries turn it over fine (One works as well as two, but just not as long...no alternator)...

The battery industry has consolodated so much lately I would be loathe to recommend any brand...often the same manufacturer makes batteries for many brands...hard to know which is good anymore *G* Personally, I just get the Duralasts from Autozone (7 year pro-rated warranty) and use them 'till they die and take them back for warranty.....most last 4-5 years. Others might be better but I don't feel like driving a half hour into town to find them..*G*

Good luck!
 

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I went with an Optima marine battery for my high comp engine....
11:1+

it works fine too....and this is with a stock starter.....it kind of has a bit of a hesitation but once it turn over a second time it fires right up.....

The Blue top Optima (to match the blue shaker base, block
and kickdown levers etc....

regards
 
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