Thread: Racing Battery?

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I wanted to get some advice from someone regarding a good 12v battery. I'm running a 12v Interstate battery on my race car, which is a 350cu.in. with 13.5:1 compression. It starts okay but after I make a run and come back for another run, it won't crank over. If I let the engine cool down (overnight) it'll crank over then.

What kind of high performance 12v batteries do some of you guys use? I really don't want to go to a 16v battery or have to run 2 12v batteries.

Thanks,

Ron

Sounds more like a starter issue to me.... One thing I like to put on my bracket cars for quick turn time between rounds is a switch to cut out the ignition.... Hit the power switch, then the starter button to get the engine spinning good, then turn on the ignition switch..... Really helps~!!!!!

Thanks for the info, however, I jumped started my car when it wouldn't crank over, so I don't think it's the starter. When I put a voltmeter to my battery, it's cranking out around 12.5 volts. I just think I need a battery with higher cranking amps, i.e. Powermaster, Total Power, Optima, etc.

Ron

I use optima red top... Lots of guys run yellow top especially those without alternators. I often put a jump box on the batt to charge it up a little between rounds (usually just once on a race day) if I notice volts at idle on the low side. Many racers use a charger after every round but then you need to mess with a generator or find an outlet. I would also suspect the starter or quality of the connections especially grounds both at the motor and the battery.. When hot all are less efficient from higher resistance

-Chris

How much initial timing are you running? If it does not retard at cranking speed it will be hard to crank against the ignition like the others have already mentioned.

I also think you have more going on than just a weak battery. Is your battery in the trunk? What size/ type of battery cables? Where does your ground cable go? What kind of starter are you running....stock or hi performance gear reduction? The thing that makes me wonder is how it dies just after one run. With the proper set up you should be able to crank it time after time. There is more we need to know.

You need the fattest cables you can get, something like 0 or 2 gauge, with both cables running right to the starter.

Don

800 to 1000 amp will most likely fix it.

With the higher compression engines this is a common problem. But I'm inclined to ask about the starter too. If it is too close to the exhaust, it will heat up and need more juice to crank over the engine which is hot, expanded and tougher to start. Had a similar issue with a Vette. The gear reduction starter with a lower profile housing worked great. The smaller housing keeps it farther away from the headers, so it stays cooler, the gear reduction, just makes thing easier for the starter and the battery.
What type of starter are you running? If this isn't it, then like people said above, cables, ground and bigger battery may be needed.

Check the distributor and the coil of the battery.

Optima yellow top for racing applications. Also, check your ground straps, add an extra one directly from the starter to the frame (you do have one from the engine to the frame now, right?). Should be good to go from there.


Bill S.

Thanks for all your help...turns out my internal regulator in my alternator wasn't working due to too small of a guage wire from my alternator to my battery. I ended up rebuilding the alternator with 120amps and getting the Optima Yellow Top D31T, their biggest and baddest battery....that took care of the problem.

Ron

I'm glad you got your problem fixed Ron.
I had the same problem a while back.
I had installed a new battery new wires and a new
starter that didn't fix the problem.
So I ran a big ground wire straite to the engine block.
I still had the same problem so I ran the ground straite
to the starter and fixed the problem.
Still not sure why the ground to the block didn't work.
So I run all my grounds straite to the starter now.
And the engine cranks twice as fast now too,
No problems since. Kurt