S197 3V Fabman's build; How did we get here? Build Thread

[Fabman]

Electric water pump can't be doing that battery any favors. I went through an Anti gravity in 2 months. Put a Motorcraft in it, the weight won't be terrible and it will give you the reliability you seek. JMHO. Good luck getting back out there.

I do have a brand new s550 alternator that I bought because that's all I could get on a race day when the first boss 302 alt failed.
I've kept it as a spare, I only ran it for one race. Any reason I shouldn't run that or should I just order another Boss 302 alt?

 

[steveespo]

I do have a brand new s550 alternator that I bought because that's all I could get on a race day when the first boss 302 alt failed.
I've kept it as a spare, I only ran it for one race. Any reason I shouldn't run that or should I just order another Boss 302 alt?

The main lug position is different but the plug connector is the same. My S550 body harness works with both alternators, I don't know if your early S197 harness will reach the lug position. Other than that no real issue, and depending on the spec of the S550, it may have a higher capacity than the Boss one. On paper that is.

 

[Fabman]

The main lug position is different but the plug connector is the same. My S550 body harness works with both alternators, I don't know if your early S197 harness will reach the lug position. Other than that no real issue, and depending on the spec of the S550, it may have a higher capacity than the Boss one. On paper that is.

Yes, I ran it already for one race and it works.
My logic was that the Boss 302 alternator might have bigger bearings as it was meant for higher RPM.
Also the lower amperage of the Boss unit would have less parasitic drag than a higher amp alternator for an s550.
No idea if either of those ideas are true, but that's what my reasoning behind the selection was.
Anybody have input on the subject? I'm all ears.

 

[honeybadger]

I'm stilling using my original 2016 GT350 alternator and I spin up 8500. Powers the water pump and coolshirt system. I do run it standalone. No plug into the ECU.

Also using AG batteries - again no issues with the ATX-HD line of them

 

[Fabman]

Photo by @purposebuilt_trevor and @speedsf_track_events www.YouTube.com/c/salmolinare.

 

[Fabman]

Well looks like my assumptions were correct.
Now the question is, how do I improve on it?
I have heard “battery” from a few sources. I have another identical antigravity battery….should I add it to the system for more spike capacity?

 

[honeybadger]

Well looks like my assumptions were correct.
Now the question is, how do I improve on it?
I have heard “battery” from a few sources. I have another identical antigravity battery….should I add it to the system for more spike capacity?
View attachment 103747

are you thinking you need more amp hour capacity? or current flow? or something else?

These little lithium batteries typically have better current limits, so an extra likely wont help there. And mine runs my electric water pump, coolshirt system (no ice, so it pulls 25 amps), trans/diff coolers and pumps, etc. all that without issue. I typically have it run my coolshirt system for 10 mins before going out and then let it continue cooling stuff down with the engine off in the pits for 10-15 mins and I've never had it die on me. I run the ATX-30HD, but survived on the 20HD model for a while as well.

do you run yours standalone? Or is it communicating with the ECU

 

[GAR944]

Well looks like my assumptions were correct.
Now the question is, how do I improve on it?
I have heard “battery” from a few sources. I have another identical antigravity battery….should I add it to the system for more spike capacity?
View attachment 103747

Be really careful connecting 2 independent lithium-ion batteries together. Talking with one of our guys who has a battery system for his solar and was getting around to joining up his 2 systems. Very little internal resistance in the batteries so a small difference in voltages between them can result in BIG currents flowing between them when connecting. See below. The issue with 2 batteries is they each have an internal charging system monitoring their internals doing independent things at the same time. Meaning different voltages again.
A lead-acid battery will take more "spike" as it is a chemical reaction storage, not so happy with bouncing off curbs.

Was going to suggest overdrive pulley but then actually read the clip you posted. The one way clutch is interesting. Could just up the overdrive until the charge light comes on at idle. My 944 just needed the occasional stab of the throttle to keep the light off. The 944 series guys here ran subaru alternators as they were tiny, ie less rotating mass. All depends on how big an electrical load is in your car.

 

[Fabman]

are you thinking you need more amp hour capacity? or current flow? or something else?

These little lithium batteries typically have better current limits, so an extra likely wont help there. And mine runs my electric water pump, coolshirt system (no ice, so it pulls 25 amps), trans/diff coolers and pumps, etc. all that without issue. I typically have it run my coolshirt system for 10 mins before going out and then let it continue cooling stuff down with the engine off in the pits for 10-15 mins and I've never had it die on me. I run the ATX-30HD, but survived on the 20HD model for a while as well.

do you run yours standalone? Or is it communicating with the ECU

As far as I know it’s stand alone but we’ll have to hear from @Albino500 as he wired up the car. I have a similar load, electric water pump, cool shirt, EPAS rack but no cooler pumps.

 

[Fabman]

Be really careful connecting 2 independent lithium-ion batteries together. Talking with one of our guys who has a battery system for his solar and was getting around to joining up his 2 systems. Very little internal resistance in the batteries so a small difference in voltages between them can result in BIG currents flowing between them when connecting. See below. The issue with 2 batteries is they each have an internal charging system monitoring their internals doing independent things at the same time. Meaning different voltages again.
A lead-acid battery will take more "spike" as it is a chemical reaction storage, not so happy with bouncing off curbs.

Was going to suggest overdrive pulley but then actually read the clip you posted. The one way clutch is interesting. Could just up the overdrive until the charge light comes on at idle. My 944 just needed the occasional stab of the throttle to keep the light off. The 944 series guys here ran subaru alternators as they were tiny, ie less rotating mass. All depends on how big an electrical load is in your car.

View attachment 103750

Yeah I was worried about that too….batteries like to run voltage between them and could overheat. I have a line on a couple different pulleys but not sure if any of them have the clutch or not. That’s my project for the week.

 

[Fabman]

 

[captdistraction]

Anecdotal - back when I raced my local safety guy and I would have this unpleasant exchange more times than I liked: "(as he's hooking up to my front tow hook) Still have that antigravity battery, huh?"

 

[steveespo]

Anecdotal - back when I raced my local safety guy and I would have this unpleasant exchange more times than I liked: "(as he's hooking up to my front tow hook) Still have that antigravity battery, huh?"

Racing level heat is the enemy. At standard temps they are fine, but wherever you mount in a race car heat is an issue for Li batteries. Under hood, hot, in trunk, hot. In cabin, hot, and NFW as I have seen 3 Li battery fires and a firewall at least gets time to pull the handle and get out.

 

[Fabman]

Racing level heat is the enemy. At standard temps they are fine, but wherever you mount in a race car heat is an issue for Li batteries. Under hood, hot, in trunk, hot. In cabin, hot, and NFW as I have seen 3 Li battery fires and a firewall at least gets time to pull the handle and get out.

Yeah, I burned my car down once already....hard lesson.

 

[honeybadger]

this brings up a good point. Where ya'll mounting them? Mine's always been mounted in the cabin with me. Could be a reason it survives

 

[Fabman]

this brings up a good point. Where ya'll mounting them? Mine's always been mounted in the cabin with me. Could be a reason it survives

In the cabin, in a foam lined plastic box.

 

[Fabman]

Behind where the passenger seat would be.

 

[GAR944]

I think this is like a bit of a loop hole in the regs that hasn't really been thought about. The lithium batteries themselves are a self feeding fire source and as such really should be behind a firewall. Whether that is a metal box over them in the cabin or trunk if rear seat area is properly enclosed or back in the engine bay. The other requirement would be a decent size vent tube arrangement to get toxic gas out to atmosphere away from the cabin.
I think it will happen when a couple catch fire at the track and everyone panics.

 

[Fabman]

I think this is like a bit of a loop hole in the regs that hasn't really been thought about. The lithium batteries themselves are a self feeding fire source and as such really should be behind a firewall. Whether that is a metal box over them in the cabin or trunk if rear seat area is properly enclosed or back in the engine bay. The other requirement would be a decent size vent tube arrangement to get toxic gas out to atmosphere away from the cabin.
I think it will happen when a couple catch fire at the track and everyone panics.

Yeah, I already burned one down a while back. It was awesome.

 

[honeybadger]

Yeah, I already burned one down a while back. It was awesome.

I missed this. do you know what caused it?