Originally Posted by
MonzaRacer
sounds more like you have other issues as your battery should handle this load if big enough, as a set of fans, fuel bump and msd shouldnt be pulling more than 30 amps and it really sounds like your starter cabling or to indirect of a ground path is starving the starter, remember resistance goes up as things get hot.
I was wondering which battery are you using and what are the specs on it?
Lets put it this way a good heavy starter even on a high compression engine shouldnt pull more than 250 amps when old. My old Pontiac had a 10.5 to 1 engine with a ridiculously low duration cam and it was a bear to start and it started with a 525 amp ac delco and boosting from my little 40 month autoworks battery and that engine even pushing nearly 275 cranking psi would fire up and never draw over 200amps.
Few things to look for, get a good digital volt meter, set it on ac volts and look for excess ac current with car running, if it goes over 50 to 60 milliamps
(0.050-0.060) and its better if nearer to 0.040mA AC current you have diodes bleeding too much ac current into your battery and it damages and drains them.
another thing even most of the larger fuel pumps should pull over 10 amps and fans around 20 amps(I had a super heavy duty one I cant remember where I got it and it only pulled 12 amps on high).
If you look for a battery look at reserve capacity and the CCA and CA. the lower the reserve the cheaper the battery and if the battery is say 600cca but 950 CA its not a good battery. kind of like the "1000" watt amps that only actually make 100 watts RMS. its bs number to sell them.
Look for high reserve capacity and high CCA like 800-1000 and CA should be within 200-250 amps. Then go over your connections, I use 2/0 battery cable to starter I crimp and solder all my connections, and use many grounds like the woven stainless braided ones. I try to put 4 on an engine 2 front and 2 back and 2 to body for 6 total. Electricity does weird things and I have shut up many a cars radio whine when rewiring and adding grounds.