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Old 11-30-2018, 12:34 AM   #11
DailyDriverSst
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Default Re: 1 battery or 2, 12V

The battery cables are about 3 years old. The connectors are copper plated and the wire is 100% copper. The connections were crimped first, then soldered.

The issue isn't that the engine spins over slow (at least, at first). It's that it takes about 30 seconds of spinning before it starts to cough and start firing. About that time is when the starter slows down and it gets into a low voltage situation where the fuel injectors won't fire with the starter spinning. If I'm lucky, i can keep it spinning fast enough that when i release the starter, the injectors will start to fire while it's spinning down and it will start running on it's own. Usually that isn't the case. (Also, the whole starter/injector conflict is common on all the 97-05 dodge trucks. The low voltage cutout for fuel is somewhere around 11.25, spark cuts out around 10.5).

Even though it's on pump gas, it's starting ability is up there with a low compression N/A alcohol engine. It just doesn't like being cold.

I'm considering adding a 120VAC block heater over winter to help get the engine warmed up a bit, but I'm also considering adding the second battery so that I can keep spinning it over until it catches at full speed. With a group 75 battery one would think there would be enough reserve to last longer than that, but it's also a 4 year old battery.
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Old 11-30-2018, 05:53 AM   #12
1320racer
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Default Re: 1 battery or 2, 12V

whose starter?
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Old 11-30-2018, 09:52 AM   #13
Tom Goldman
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Default Re: 1 battery or 2, 12V

Your issue is not uncommon amongst EFI cars .
I have a lot of EFI stockers come thru the shop and it is something I've seen happen on several older built cars .
I am defiantly a proponent of dual batteries , the reserve they offer comes in handy when going rounds with minimal time to charge the batteries . ... . Running an alternator is a must with any EFI car to keep the voltage above 12.5 v.
Two areas that are overlooked are grounding and master disconnect switch .
I see many cars with no ground wire between the frame and engine or battery grounds bolted to the sheetmetal floor.
I have seen 2 cars this year with problems due to disconnect switches with high resistance /voltage drop issues. ….look at the amp rating of the most common disconnect switches with 3/8" studs ,most are only rated for 125-150 amps intermittent {starting} current . while the heavy duty ones from Moroso or Flaming river are rated for 1000 amps or higher intermittent current.
One last thought regards the wiring of the ECU itself . Holley in particular is adamant about having the ECU connected directly to the battery with no interruptions.
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Old 11-30-2018, 08:32 PM   #14
voltdr
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Default Re: 1 battery or 2, 12V

Always remember that heat is the enemy to EVERYTHING......... When your starter is cranking over for 30-45 seconds, it is building a lot of heat inside the starter itself. More heat equals more friction. As someone mentioned, as the voltage drops the amperage goes up. It can be a snowball effect. I run the same size (as the positive) ground wire from the battery directly to the block. Chromemoly is not a good electrical conductor. Soldering your connections is good IF done properly. Not everyone knows how. A fully charged 12V battery should read 12.6V after the surface charge is dissipated. If your battery is reading 12.1V. It will take approx. 10 hours to charge the battery using a 10A charger. I'm going from memory, I used to have a chart from AC Delco but not anymore. The point is that it takes longer than you think to charge a battery. Charging for 20-30 minutes between rounds is NOT adequate. Buy a good battery charger that is made for your type of battery and keep it on your car anytime the car isn't running. I've never seen anyone lose a race because their car started but a lot because it didn't.
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Old 11-30-2018, 09:01 PM   #15
DailyDriverSst
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Default Re: 1 battery or 2, 12V

Quote:
Originally Posted by Tom Goldman View Post
Your issue is not uncommon amongst EFI cars .
I have a lot of EFI stockers come thru the shop and it is something I've seen happen on several older built cars .
I am defiantly a proponent of dual batteries , the reserve they offer comes in handy when going rounds with minimal time to charge the batteries . ... . Running an alternator is a must with any EFI car to keep the voltage above 12.5 v.
Two areas that are overlooked are grounding and master disconnect switch .
I see many cars with no ground wire between the frame and engine or battery grounds bolted to the sheetmetal floor.
I have seen 2 cars this year with problems due to disconnect switches with high resistance /voltage drop issues. ….look at the amp rating of the most common disconnect switches with 3/8" studs ,most are only rated for 125-150 amps intermittent {starting} current . while the heavy duty ones from Moroso or Flaming river are rated for 1000 amps or higher intermittent current.
One last thought regards the wiring of the ECU itself . Holley in particular is adamant about having the ECU connected directly to the battery with no interruptions.
Thank you, Tom. This agrees with what the Dragpak owner told me at the Noble divisional.

The master switch is a Longacre 2-terminal (not sure what that would be rebranded from) and the EFI is as Mopar installed it at the factory. Not sure if the disconnect is 52-45760 or 52-45754, but i'm thinking the former.

Both cylinder heads are grounded to studs on the firewall by factory mopar braid, and I added a #10 ground wire between studs and from one stud to the frame. I am not sure if there is a ground strap off the block or not. Battery is grounded to the frame with a #2 wire 18" long, again connectors are crimped and soldered. Battery itself has marine connectors on it.

I plan to completely re-ground the engine bay over winter to follow the procedure we normally have on our cars, with daisy chained #10 ground wires all the way around and back to the battery, redundant to the chassis.

I guess I'll also plan on adding a second battery.

1320, it's the factory late model Denso-style gear reduction starter for all Mopar platforms (not the earlier style that was the size of a watermelon).
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