Did a 58 pound AGM/conventional battery conversion to an Antigravity ATX-30-HD 970 cranking amp 5 pound battery. Some on the X152 forums had great success with this and I did too apparently as no problems so far.

 

Has the handling improved?

 

I did this in my 1995 Acura NSX....went from roughly 40# to 8# (or less). For a car with less than 270bhp...it was noticeable. At least to me, that is.

Not sure how this would be helpful here as our cars are very torque-y and have plenty of HP. But what do I know.

More importantly to me, how does this handle the electrical gremlins?

 

Haven’t tossed it about just yet. I may fit the Sparco buckets this week which’ll get me close to 500 pounds saved, total to date. That, I reckon, will be very evident.

 

No gremlins whatsoever, plenty of power, it just doesn’t have the ‘reserve’ of a larger Ah battery. But for my application that should never be an issue.

 

I'm concerned about a 12V lithium-ion battery in a car, especially a race car that wasn't designed for it. We know that low voltage lithium-ion batteries in laptops, hoverboards, and other devices have caught fire in airplane cargo holds. What risks, if any, does that L-ion battery pose in your race car?

I know nothing about track safety rules and wonder if retrofitted L-ion batteries are acceptable without modifications such as an onboard fire suppression system.

Or are my concerns unfounded?

 

Fair question. Lithium batteries have been used for years in McLarens as standard fitment and as optional fitment in Porsche and BMW among others. This is a premium brand product built specifically for motor sports use and has a built in BMS system for temperature and charging protection and for use with any profile type of automotive charging system. However what’s important is the type of external charger used for maintenance.

 

Should it?! I thought about this mod and finally decided not doing it. XK has too light rear (for me) and I was worried that it will only get things worse.

If a battery is on a front of a car (originally) - I would definitely do this change.

Really curious about feedback on that.

 

500lb weight reduction is massive , not only will track times come down significantly you should also be close to half a second quicker down the strip ..well done !!

 

Jeremy has adjustable coilovers so he can dial them in to compensate any issues in the rear end (back too light etc)

 

Yes every-time I strip something off I have to redo the corner balance 😭 but at least able to manage perfect cross weight and suspension alignment to keep it glued to the road. Really anxious to see how it’s going to balance with the new seats.

I reckon I’m out of easy options to shed more weight. I’m considering eliminating the fuel tank in favour of a fuel cell bit after that, the price per pound is going to go up dramatically.

 

Had a quick look as I started thinking subframe we have heavy *** steel (front & back) whilst f type has steel (rear) and alloy (front) .

I know the rear bolts up to x150 from x152 however not so certain on the front although we can bolt up f type racks (non electric) to our front subframes so we could be onto something ?

Would need a breaker to measure mounting points for us
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Trying to save weight but still have that ancient DVD player in there ...

 

That’s the NAV drive, which I’ve never used 😂 but it weighs less than a pound, what’s the point in removing it? I don’t use Bluetooth, CD and radio either, but I do use the Apple interface for music.

 

Think some one is stirring the pot , for once I thought we were actually going to have a insightful thread .

 

Steve, at one point I spoke with a fabricator about templating and making aluminum versions but his concern was they may not have the structural integrity of the OEM versions. Have you weighed up the ugly steel ones?

 

No confirmed weights however I've had mine out twice and its heavvyyy, when I'm working on mercs or BMW its remarkable at how light they actually no problems picking them up with one hand.

I wouldn't hesitate for one moment to fit one up in my car its been a gripe of mine since day one as they have saved a truck load of weight on the body yet put in heavy steel subframes ..I wouldn't say a structural issue as other high end manufacturer use alloy I would put it down to saving s few bucks for them

 

The safety implication of Lithium was my first thought also, although when you read up there are more garage fires because of rechargeable yard tool batteries than most anything else. That is a pretty decent weight savings and right in line with what you are looking to accomplish with cumulative number. So well worth it!

I have seen your weights in the back of some pictures you posted so I know you are slinging steel around for fun, I am sure heavy to you is not heavy to some of the others. Your one handed pickup may be two for others! I have pushed and pulled a lot of weights over the years...still do.

 

Haha guilty as charged a bona fide iron slinger !!

Oh how ive missed this driveway perfect for uphill lunges !!

 

Follow up to report how fantastic this battery is. Has not been on the CTEK since fitted. Driven rarely and for short distances only until track season resumes later this year. Battery at full charge, all electrics operating correctly, wish I'd done this years ago. Certainly appears significantly more reliable than even AGM.