[KevM2]

Originally Posted by baron95

Don't overthink it.

You are changing ~1% of the weight of the car, or the equivalent of 6 gallons of gasoline. It will affect the handling as much as the difference between a full tank and a half tank? Can you tell the difference as you burn gas?

If you really want to find tune the handling, just varying the tire pressures front to hear, will have a much greater impact on balance. And using (trail)braking and throttle at the right time will have a greater impact still.

911s with 40F/60R can understeer, and Civic Type R with 60F/40R can oversteer. Don't listen to people bitching that car X understeers. They simply just want clicks or can't drive or both.

Yeah I guess you’re right… never thought of the weight changes with fuel and that puts it in better perspective

[aerobod]

Originally Posted by baron95

Don't overthink it.

You are changing ~1% of the weight of the car, or the equivalent of 6 gallons of gasoline. It will affect the handling as much as the difference between a full tank and a half tank? Can you tell the difference as you burn gas?

If you really want to find tune the handling, just varying the tire pressures front to hear, will have a much greater impact on balance. And using (trail)braking and throttle at the right time will have a greater impact still.

911s with 40F/60R can understeer, and Civic Type R with 60F/40R can oversteer. Don't listen to people bitching that car X understeers. They simply just want clicks or can't drive or both.

We were running my son’s almost stock Toyota Echo at the track yesterday (back-up car, a- la Top Gear , but still good fun). It is on R-comps with front camber and brake pads being the only other mods, 30 PSI front and 45 PSI rear tyre pressures give it lots of oversteer when needed.

[tom @ eas]

Originally Posted by Click_ID

Why not go Braile and save 8 more Lbs?
https://shopbraille.com/collections/...ithium-battery

Antigravity also has a 40Ah that weighs in at 15lb, which I specifically didn't list in the DIY. Not recommended for daily drivers, its more intended for race use. I'd feel much more comfortable with the 60Ah/80Ah packages.

https://europeanautosource.com/produ...ithium-battery

These G87s have a pretty extensive network to sustain than to just throw the smallest battery that can fit and hope for the best.

Originally Posted by baron95

tom @ eas Is there any advantage to choose H8 over H7? I'd rather have a bit more storage room for a rure repair kit or such in the remaining space.

thanks for the awesome post. I'm ordering one as soon as I'm near breaking service.

Not really, we lucked out on this one with BMW giving us dual mounting options.

[aerobod]

Originally Posted by M2siast

Did you have a metal pen in the glovebox though? Put one in there and report back if it understeers.

We prefer a good dump to reduce weight and fine tune the balance before unleashing all of the 80 WHP

[M_Power Rob]

Originally Posted by baron95

Don't overthink it.

You are changing ~1% of the weight of the car, or the equivalent of 6 gallons of gasoline. It will affect the handling as much as the difference between a full tank and a half tank? Can you tell the difference as you burn gas?

If you really want to find tune the handling, just varying the tire pressures front to hear, will have a much greater impact on balance. And using (trail)braking and throttle at the right time will have a greater impact still.

911s with 40F/60R can understeer, and Civic Type R with 60F/40R can oversteer. Don't listen to people bitching that car X understeers. They simply just want clicks or can't drive or both.

Again, two trains of thought/discussion here. There are those looking to balance the weight for best handling on a road race track and there are those looking for fastest launch (60 foot times) and pulls to 1/8 mi or stop light to stop light. Many concerned with overall weight loss (shedding pounds wherever you can) are driving in terms of drag/street racing (whether actually street racing or power launching/accelerating off the line going straight). In terms of the latter, yes, weight makes a difference including but not limited to battery shedding 40 pounds, lesser amount of gas in the tank or other weight loss in general. Yes, you will launch and accelerate off the line faster with 1/8 - 1/4 tank of gas vs a full tank of gas.

You want to go run at a 1/8mi or 1/4mi drag strip, you dont go in with a full tank or anywhere near it. You want to run just enough gas in the tank for the number of runs you plan on doing.

[tom @ eas]

Originally Posted by M2siast

This. Let’s not forget the car has an alarm as standard, and is constantly connected to the internet. If you don’t drive often, the small battery won’t be enough. Sure wouldn’t for me since I don’t drive all week…
I’d take the largest I can get.

Good point.

AG's Battery Tracker is also a good alternative for those that do not drive often or have actual seasons (unlike us in SoCal @ 70-80F every day) to check battery voltage on your phone as well as monitor the last 30 days at a glance. For long term storage, you can even set reminders on your phone to check in. I even use one of these on my motorcycle for convenience.

[tom @ eas]

Originally Posted by StockM4

Is this available for g80 m3???
If so please link

Working on it. G80/G82 platform is much more complicated.

[baron95]

Originally Posted by M_Power Rob

Again, two trains of thought/discussion here. There are those looking to balance the weight for best handling on a road race track and there are those looking for fastest launch (60 foot times) and pulls to 1/8 mi or stop light to stop light. Many concerned with overall weight loss (shedding pounds wherever you can) are driving in terms of drag/street racing (whether actually street racing or power launching/accelerating off the line going straight). In terms of the latter, yes, weight makes a difference including but not limited to battery shedding 40 pounds, lesser amount of gas in the tank or other weight loss in general. Yes, you will launch and accelerate off the line faster with 1/8 - 1/4 tank of gas vs a full tank of gas.

You want to go run at a 1/8mi or 1/4mi drag strip, you dont go in with a full tank or anywhere near it. You want to run just enough gas in the tank for the number of runs you plan on doing.

No disagreement there. I was only addressing the question on understeer. I want as much weight that can be easily and inexpensivelym removed without affecting functionality, out of my car. G80/82 takeoff forged wheels and Li-ion batteries are no brainers for me.

[baron95]

Originally Posted by aerobod

We were running my son’s almost stock Toyota Echo at the track yesterday (back-up car, a- la Top Gear , but still good fun). It is on R-comps with front camber and brake pads being the only other mods, 30 PSI front and 45 PSI rear tyre pressures give it lots of oversteer when needed.

Thank you for perfectly illustrating the point. You certainly get it.

[ToneM2]

Couple questions, I only see F87 M2 as on option on Bimmercode, did you use that to code? Some of us used Bimmercode to change some things and we used 3 Series/M3 G20 G80 option to do so.
Does a battery tender work on this type of battery? Might be putting my car in storage for a month or 2 depending on how bad winter is here in NY, another option would be to swap the OEM battery back in the car when its going to be sitting for long periods or out in below freezing temperatures.
Also, surprised to hear you say G80/G82 platform is much more complicated than the G87. I thought they were very closely related.

[dezzracer]

Based on the info it certainly appears AG has done their homework. I own several of their products for my motorcycles and happy with them. But when I need a new battery for my BMW I’ll likely have a dealer bolt one in, code it and be done with it.

[F32Fleet]

Originally Posted by g21

50/50 is a lie.
i can't think of a single modern BMW that has a 50 - 50 FR weight distribution
furthermore, porsche sports cars are around 40/60

The current M2 is advertised as 50/50.

As for Porsche you're only talking about the 911 and if you're going to be severely in unbalanced rear engine is the way to go.

Weight reduction of this Li battery is used in advertising the product so if weight distribution doesn't matter than there's no reason to buy this Li battery.

[F32Fleet]

Originally Posted by baron95

Don't overthink it.

You are changing ~1% of the weight of the car, or the equivalent of 6 gallons of gasoline. It will affect the handling as much as the difference between a full tank and a half tank? Can you tell the difference as you burn gas?

If you really want to fine tune the handling, just varying the tire pressures front to hear, will have a much greater impact on balance. And using (trail)braking and throttle at the right time will have a greater impact still.

911s with 40F/60R can understeer, and Civic Type R with 60F/40R can oversteer. Don't listen to people bitching that car X understeers. They simply just want clicks or can't drive or both.

Okay, so then why buy this Li battery? Just so you can tick it off the box of alleged improvements over stock?

[mrdudley]

Originally Posted by BeachsideF30

It’s really a bargain at 1k. I might get 2 for my excursion too

Originally Posted by Roch M4

1 000 $ for a 40 lb gain...pfff...useless and it will not work anyway in the winter here in Canada...

I mean the carbon roof is $2600 to shed ~50 pounds, so $1k is a bargain
(yes I know the carbon roof also looks better and offers more headroom)

And folks talk about wheel swapping to save 20-25 pounds. That set me back $5k (827M wheel), though I suppose I have an extra set of wheels I can sell.

[RichP]

I'm safe in assuming these batteries are not compatible in vehicles that have AGM batteries as the only option? I have a Volvo V60 Polestar and this would be ideal: Unlike in a BMW where the battery is low and in the back, the Volvo battery is pretty much above the engine, above the front wheels. Losing 40lbs there would be significant.

[GregW / Oregon]

Originally Posted by g21

50/50 is a lie.
i can't think of a single modern BMW that has a 50 - 50 FR weight distribution
furthermore, porsche sports cars are around 40/60

M2 auto is listed as 52.1/47.9. Removing 40 lbs. from the rear would change it to 53.1/46.9. Remember that fuel load can vary the rear weight by as much as 80 lbs.

[tom @ eas]

Originally Posted by ToneM2

Couple questions, I only see F87 M2 as on option on Bimmercode, did you use that to code? Some of us used Bimmercode to change some things and we used 3 Series/M3 G20 G80 option to do so.
Does a battery tender work on this type of battery? Might be putting my car in storage for a month or 2 depending on how bad winter is here in NY, another option would be to swap the OEM battery back in the car when its going to be sitting for long periods or out in below freezing temperatures.
Also, surprised to hear you say G80/G82 platform is much more complicated than the G87. I thought they were very closely related.

Tried to reply to your post last night, but the forum went down for server maintenance in the middle of posting.

You bring up a good point. At this time Bimmercode only supports up to F87, which is fine for battery coding on G87. When you get to the Battery Registration part on Bimmerlink, you can see the value is successfully read at 60Ah (instead of 90Ah), which is what we previously coded the new battery at using Bimmercode.



If sitting for long periods of time, you can opt for the Antigravity Battery Tracker to monitor voltage as needed from your iPhone/Android, otherwise you will need a LiFePO4-specific charger as not to damage the battery.

Originally Posted by RichP

I'm safe in assuming these batteries are not compatible in vehicles that have AGM batteries as the only option? I have a Volvo V60 Polestar and this would be ideal: Unlike in a BMW where the battery is low and in the back, the Volvo battery is pretty much above the engine, above the front wheels. Losing 40lbs there would be significant.

Absolutely. I've been running a AG battery in our Tesla Model Y Performance successfully for the past 2 years, as 20-22 models come with a really cheap lead acid battery that typically craps out in a couple of years for the 12V system.

[DSTR]

Originally Posted by M2siast

Did you have a metal pen in the glovebox though? Put one in there and report back if it understeers.

Montblanc of course. Understeer with style .....

[///M TOWN]

40 lbs is like going on a diet

Why the fuck not

[G30M]

Originally Posted by GregW / Oregon

M2 auto is listed as 52.1/47.9. Removing 40 lbs. from the rear would change it to 53.1/46.9. Remember that fuel load can vary the rear weight by as much as 80 lbs.

these guys weighed their M2
no driver + full tank
F:R 52.2 : 47.8
total 3762 lbs


driver + full tank
51.9 : 48.1
total 3929 lbs

so without fuel front will go up another 1%? making it 53:47?

no 50:50
also that's static

when you drive there is constant weight transfer.
when you brake this car it will be something like 60:40 - 80:20 depending on how hard you brake

hence porches are 40:60, during acceleration the rear is weighted nicely, during braking the rear doesn't get too light - so it won't drift as much, but we all want to drift, so we get the M2

[baron95]

Originally Posted by F32Fleet

Okay, so then why buy this Li battery? Just so you can tick it off the box of alleged improvements over stock?

Because reducing weight is valuable. It improves acceleration, braking and turning (specially on transitions). It reduces consumables on track (tires, brakes). It makes the car more lively and enjoyable.

20 lbs or so by going to forged wheels, 40 lbs or so by going to Li-Ion battery, alone are a drop of > 1.5% of the weight of the car. Not eart shattering, but meaningful.

[F32Fleet]

Originally Posted by baron95

Because reducing weight is valuable. It improves acceleration, braking and turning (specially on transitions). It reduces consumables on track (tires, brakes). It makes the care more lively and enjoyable.

20 lbs or so by going to forged wheels, 40 lbs or so by going to Li-Ion battery, alone are a drop of > 1.5% of the weight of the car. Not eart shattering, but meaningful.

LOL. Okay so reducing total weight by a couple of lbs is valuable but possibly upsetting 50/50 weight distribution is completely irrelevant. You are aware that this makes no sense right?