[ponjohn]

Originally Posted by R 70 Judge

These batteries are designed for use with an alternator. They do have charging voltage and amperage limits though. I’d have to look it up again but I think it was in the 240amp alternator range and it must charge below 14.8 volts. Again, I’d have to dig for the exact info but that’s in the ballpark.

Thank you. That is the reason I asked. I know / knew that there may be different charging requirements.

in my mind I was envisioning a battery conditioner / Isolater between the alternator and the battery.

[Dlaw455]

I have a 535 Pontiac with 11:1 and terminator x with cnp and use the cam and crank signals from the holley dual sync and it always starts right up no issue. I am using the XS D2700 battery listed as 1140cca with Powermaster 9410 starter. It cranks around 200rpm. I do notice in the data logs during the first half second or so of cranking that rpm does show syncing though.

[R 70 Judge]

Originally Posted by Dlaw455

I have a 535 Pontiac with 11:1 and terminator x with cnp and use the cam and crank signals from the holley dual sync and it always starts right up no issue. I am using the XS D2700 battery listed as 1140cca with Powermaster 9410 starter. It cranks around 200rpm. I do notice in the data logs during the first half second or so of cranking that rpm does show syncing though.

Nice combo you have there! Mine syncs and starts at 200 rpm as well. That seems to be enough rpm for everything to communicate properly. I’m curious which cam you are running? Ballpark specs? Im wondering how much larger/smaller it is than mine. Are you running Holley smart coils or LS coils? Do you happen to remember your dwell settings?

[GOAT8U2]

Great thread, looking like 1500ca Lithium is the threshold on power and 200rpm a known good cranking rpm minimum for insta-starts. 110rpm for both me and R 70 Judge = embarrassing efi starts.

BTW, the Antigravity techs say Lithium isn't tested in CCA so only CA numbers are real for Lithium.

I'm doing 2 cars soon with Lithium swaps so I'll add data too but so far I think we're seeing the value of the battery power and cranking rpm for aftermarket Efi.

No one was really talking about this so big thumbs up to this thread.

[Dlaw455]

Originally Posted by R 70 Judge

Nice combo you have there! Mine syncs and starts at 200 rpm as well. That seems to be enough rpm for everything to communicate properly. I’m curious which cam you are running? Ballpark specs? Im wondering how much larger/smaller it is than mine. Are you running Holley smart coils or LS coils? Do you happen to remember your dwell settings?

Thanks! I have followed your threads too. Interesting learning you have gone through. Funny fact but I went the other way than you from Northwind 4150 sniper xflow and now to the CNP 4500 mpfi with Wilson throttle body. I thought maybe I was holding the 535 with wide ports back a little. I can't tell yet but it definitely idles amd responds better now. I have the MSD smart coils set at 4.5msec dwell for street application. Cam butler specd is comp hitec lobe with 268/275 at .050, 112 lobe sep and .700 ish lift with 1.65s.

[Dlaw455]

I suspect they don't spec cca as that is a lithium battery's weak point. Probably not a real concern for us folks here though. My xs 2700d CA is rated at 1300 though. Half the cost of the Li but a lot heavier. Good things its in the trunk though. Lol

[alloy indian]

Here is my 2 cents worth. I was in the market for a Lithium battery, so I spoke to Tony the owner of Sick Goat about it. He said they had friends who tried many different brands with mixed result in the longevity department. But found that the brand called "Voltphreaks" lasted the longest they had found. So, I purchased a Voltphreaks 16-volt Lithium battery and charger...you need a specific lithium charger to charge them! Something to remember. Total with charger was $1200 a lot of money but I was after weight saving and they only weigh 8.25 Lbs. This was back in 2019 and it's still going strong. Never loses a charge even when my car sat with the engine out for a year it didn't need a charge! My engine is a 525 cube 14-1 compression 900+ horsepower carbureted engine. It cranks right up every time and to say the least I'm super happy! It even has an on off button that you can shut the battery down when not in use. It also has a sensor that will shut it down say if you left the lights on so you will still have enough power to start the engine. I've never had an issue but there is one thing the Voltphreaks website is no longer up, and I don't know if the company is still around, I hope so because I would definitely buy another one if and when this one dies.

[GOAT8U2]

Just got the ATX-30HD 970ca for my GN, no car terminals included and their little mounting block is M6 so nothing fits.

I need the posts with threaded top mount and the Shuriken SAE20 are 10mm too long of screw (short screw one).

R70 Judge, you buy the Anti terminals AG-TA-1?

[R 70 Judge]

Originally Posted by GOAT8U2

Just got the ATX-30HD 970ca for my GN, no car terminals included and their little mounting block is M6 so nothing fits.

I need the posts with threaded top mount and the Shuriken SAE20 are 10mm too long of screw (short screw one).

R70 Judge, you buy the Anti terminals AG-TA-1?

That’s a bummer. No, my AG-24-60-RS came with the terminals. I think the battery you got is more geared towards moto sports applications, so maybe that’s why they weren’t included? I guess I didn’t take any pictures of the new set-up but I have some of the old battery and billet blocks. High quality wiring is imperative. Oxygen free copper (OFC) 2/0 power and grounds. 1/0 OFC from battery to starter

[GOAT8U2]

That looks nice, I like the extension off the posts for other power needs.

They said the same thing, ATX-30HD is still considered a motorcycle battery, though it's 970ca and their best seller because autos are buying. Charge $10 more, throw in terminals, big deal, it's $560 already and this battery is clearly the one cars that don't need over 1000ca are buying for the weight and cranking power vs motorcycles who clearly don't need 1000ca.

I'm gonna test this in my GN first and log, then try in the GTO and see if this is all we need to fire fast.

[GOAT8U2]

So early results...

Napa 800cca battery, 190rpm cranking, mostly 3+ sec cranks and many 5+ sec.

Antigravity ATX-30hd battery, 140rpm cranking but in the 4x I've started it, every time starts within 1 sec????

I'll post logs soon, don't have them on my phone but there might be something else at play here beyond my pay grade.

ATX-30hd was 13.3 volts fresh from Antigravity (they are the only ones that sell this battery, all other batteries vendors can sell).

Maybe the starting and cranking volts are helping other components fire up faster and cranking rpm is one strong variable but not the end all.

[Shiny]

Volts at battery terminal while cranking might help interpret.

We're cables the same for both?

[R 70 Judge]

Originally Posted by GOAT8U2

So early results...

Napa 800cca battery, 190rpm cranking, mostly 3+ sec cranks and many 5+ sec.

Antigravity ATX-30hd battery, 140rpm cranking but in the 4x I've started it, every time starts within 1 sec????

I'll post logs soon, don't have them on my phone but there might be something else at play here beyond my pay grade.

ATX-30hd was 13.3 volts fresh from Antigravity (they are the only ones that sell this battery, all other batteries vendors can sell).

Maybe the starting and cranking volts are helping other components fire up faster and cranking rpm is one strong variable but not the end all.

Since it starts so fast you could try unplugging the coils to get a better read on the cranking rpm just for testing purposes.

[R 70 Judge]

Originally Posted by Shiny

Volts at battery terminal while cranking might help interpret.

We're cables the same for both?

Agreed. Voltage drop is also a good thing to look at

[GOAT8U2]

Exact same everything, battery swap done within minutes of each other logs.

Napa 800cca = 11.4v cranking average
Antigravity 30hd = 12.2v cranking average

The cranking volts is almost a full volt higher so maybe that's a big piece of this vs just battery cranking amps in general.

I will say this, if this does the same thing in my GN then saving $500 vs the Antigravity Group 24 battery makes me happy since I wasn't pumped about a $1050 battery.

[GOAT8U2]

After a bunch more starts today that are within 1-2 seconds tops, this is legit and cured my issue. I'd get lucky and have 1-10 starts like this with the 850cca (probably 950ca) battery and a bunch of embarrassing ones but not even 1 on 10 with the Antigravity so far was even close to bend sad, the are all awesome or normal Efi starting you'd expect.

Now holding down this little gremlin is turning into a chore, got on McMaster Carr a

5/16 -18 x 8" bolt coming for the factory hold down and threaded hole.

[mysticmissle]

im of no help in the lithium battery department, but i am running 16 volt system with my holley efi, a converted 12si alternator, and a 16 volt turbo start battery. more is def better in my experience. I was running it with the carb and magnafuel 500 pump for better starting this car will never go back to 12 volt. i may be able to get a cranking rpm number for you next time its off the storage lift.

[Shiny]

I'm sure you are happy it's working better now!

I expected higher voltage to generate higher cranking rpm, but seems not for you...

Originally Posted by GOAT8U2

Exact same everything, battery swap done within minutes of each other logs.

Napa 800cca = 11.4v cranking average
Antigravity 30hd = 12.2v cranking average

....

Originally Posted by GOAT8U2

So early results...

Napa 800cca battery, 190rpm cranking, ....

Antigravity ATX-30hd battery, 140rpm cranking .....

Can anyone explain why a battery delivering higher voltage to the same motor wouldn't make it spin faster? Is this because the Antigravity battery can't deliver as much current, even at the higher voltage? In other words, is the torque of a starter motor current-limited, independent of voltage?

Mike

[Lee]

Originally Posted by cdrookie

I had a 17 pound Blaille battery in my car for many many years, got it in Summit's discount section. Being a project car it sat forever, and there was something drawing off of it as it would go dead after xx days if I didn't remove a cable. It would charge back up and be good as new, that battery was impressive. It finally gave up about a year ago.

I've had great results with Braille and XSPower AGM's. One XSPower worked great for over a decade, and a Braille lasted 12+ years.

CCA's are VERY misleading on AGM's, compared to a lead-acid. In my experiences, a quality AGM (not the AutoZone/O'Reilly "AGM") with about 400CCA will outperform a lead-acid of 1000CCA.

I've used the XS Power S925 and S975 with several larger inch street/strip motors, and they were more than powerful enough (and less than half the weight of a lead-acid). About the same cost as most lead-acids now, too.

Lithium looks interesting, but I'm happy with the AGMs at this point.

[GOAT8U2]

Update...

Completed the full Antigravity install, got a new battery tray and then drilled through it for the Antigravity tray to be solid.

Antigravity ATX-30hd 970ca (7.25lbs) 7-25
AG-TA-1 terminals (M6)
AG-BT-LC-30 battery tray
Hold down bracket bolt OEM = 5/16-18 x 8
OEM battery tray GMK433230068
5/16-18 SS bolts into car body
AG-BT-LC-30 holder for ATX-30HD battery
Ag holder screws into OEM tray 1/4-20 x 1
Vgate terminals (M4, M5, 1/2" nut)