Standard battery v race battery

[A911DOM]

I need to replace the tired battery in the 944 and am wondering if Im better off to shell out on a race battery which should be much lighter plus giving increased charge?

The cars only going to get used for trackdays (unless I decide to sneak an MOT on it at some point).

Whats other experience / opinions on this?

On a recent trip into Halfords, I notice the price of standard batteries seems to have rallied somewhat - is it going to be a completely false economy putting a budget battery on it despite the only occasional use?

TIA

[mmm-five]

I thought race batteries tended to be smaller because they were less powerful than standard batteries, based on the fact that they don't have to run for as long nor power lots of electrical items, nor start the car multiple times.

If you're not bothered about the cost, then some of the high-power gel batteries are significantly smaller/lighter.

http://www.powervampracing.com/odyssey_car_batteri...

[A911DOM]

mmm-five said:

I thought race batteries tended to be smaller because they were less powerful than standard batteries, based on the fact that they don't have to run for as long nor power lots of electrical items, nor start the car multiple times.

If you're not bothered about the cost, then some of the high-power gel batteries are significantly smaller/lighter.

http://www.powervampracing.com/odyssey_car_batteri...

These are the very fellas Ive been looking at actually - and Ive just a had an email back from their sales support.

Perhaps this is my misunderstanding but, I thought I'd been told that the race batteries put out a bigger charge, and also weigh much less so you win on both accounts.

I dont want to spend a fortune as this is only a track toy afterall.

[A911DOM]

and here is the very helpful response from the guys at Merlin Motorsport www.merlinmotorsport.co.uk) re the Odyssey battery:

Hi Dominic

There is not a recommended battery (for the 944) as such, I would be inclined to use the Odyssey 30. However smaller batteries may start the car but the issue you really need to be are of is you can not leave these batteries on the car as drain them will lead to a premature failure of the battery and with these batteries this can easily be done, they have high starting currents, but they do not have the Amp Hours to deal with parasitic drain. So whatever battery you end up with I would recommend that you remove it from the car and place it on the dedicated charger between uses.

Just so you know the background for these batteries; they were originally designed for starting only. If you use the car on the road you need to be especially careful.

I hope this is of use.

Regards

Gary


I think thats what used to be called customer service
I shall reply and tell them so

Edited by A911DOM on Tuesday 5th January 12:45

[mmm-five]

You could easily use one of their smaller ones to start the car and have enough power to keep the heater fan going in the colder weather, but make sure you remove it between track days and give it a top-up charge the night before you go on track.

[7 Sevens]

I can't access the merlin site from work but are they supplying a Varley Red Top? Should be much lighter and has a higher output from memory. I think you are correct in that they don't have as much power, what they should do is to increase the strength of the initial voltage to start.

If you/they are worried about it draining how about fitting an isolator switch like on most race cars. i.e. One/two of those red keys that isolate and cut off the battery.

[tony.t]

A911DOM said:

I need to replace the tired battery in the 944 and am wondering if Im better off to shell out on a race battery which should be much lighter plus giving increased charge?

The cars only going to get used for trackdays (unless I decide to sneak an MOT on it at some point).

Whats other experience / opinions on this?

On a recent trip into Halfords, I notice the price of standard batteries seems to have rallied somewhat - is it going to be a completely false economy putting a budget battery on it despite the only occasional use?

TIA

I use an Odyssey PC680 on my 964 because the weight savings are significant. It's been on 4yrs now and although I suspect it's nearing the end of it's useful life it will still start the car.

The 964 is a track only car and has a bare minimium of electric devices. The parasitic drain must be very low as the battery will retain charge between trackdays without attention. Alarms are the worst culprits for parastic drain IMO.

I have a large car battery jumped across to the Odyssey when not using the car for any period of time which I put on charge when I remember. Never have any problems starting the car.

[A911DOM]

Handy to know - thanks!

Like the car too (obviously). Im not brave enough to unleash myself on track with the 3.2

[tertius]

I was planning to do this for the Elise and wondered what the smallest battery I could get away with would be. I'd certainly fit a battery isolator switch for the between track days time but it does get used on the road as an ordinary car a little bit.

Anyone know?

[v8bloke]

A year ago I swapped my std battery for a Red top 20. When I first saw it, I thought there was no way that it could possibly be man enough but its been great. Saved 10kg
Car is an MGB with 10.8:1 cr 4.6 V8, starts beautifully. ( gear reduction starter )
Of course engine is british engineering so always starts first time.
I Always flick the battery switch off when left. Car has bare minimum of electrics.

http://www.youtube.com/watch?v=lWa4n7iVCm8

[Elderly]

They have advantages: they have a very high cranking power for their size and they hold their charge extremely well for long periods of time (the colder the ambient temperature the better), but (as already mentioned) any small constant current drain will ruin them - a clock or an alarm spring to mind.

[fiveoclockhero1]

tertius said:

I was planning to do this for the Elise and wondered what the smallest battery I could get away with would be. I'd certainly fit a battery isolator switch for the between track days time but it does get used on the road as an ordinary car a little bit.

Anyone know?

I've got one on my VX220, it's an odyssey 25 (old part no: pc680), the cranking power is about half as much again as the standard battery, in fact I used it to start my 2.5 litre diesel transit and it spun it over a treat. You can mount them in any position you want. Its about 6 kg lighter than the standard battery which for the elise/vx is not ideal as you really dont want to take weight off the front. I've got an isolator switch on it too. The terminals are 6mm thread female and you need to buy the 6mm male posts to fit it.

[tony.t]

Odyseey 25 (PC680) weighs 6kg IIRC - I'm sure my first mobile phone battery was heavier

[GC8]

I use an Odyssey on my light 944 and its been faultless.

[pikeyboy]

I jump started my merc 3oo td estate from a small red top 25 (i think) off my race car when i flattened the battery after i ran it out of fuel.

[tertius]

fiveoclockhero1 said:

tertius said:

I was planning to do this for the Elise and wondered what the smallest battery I could get away with would be. I'd certainly fit a battery isolator switch for the between track days time but it does get used on the road as an ordinary car a little bit.

Anyone know?

I've got one on my VX220, it's an odyssey 25 (old part no: pc680), the cranking power is about half as much again as the standard battery, in fact I used it to start my 2.5 litre diesel transit and it spun it over a treat. You can mount them in any position you want. Its about 6 kg lighter than the standard battery which for the elise/vx is not ideal as you really dont want to take weight off the front. I've got an isolator switch on it too. The terminals are 6mm thread female and you need to buy the 6mm male posts to fit it.

Cheers, mine's an S2 so the battery is at the back.

[fiveoclockhero1]

tertius said:

fiveoclockhero1 said:

tertius said:

I was planning to do this for the Elise and wondered what the smallest battery I could get away with would be. I'd certainly fit a battery isolator switch for the between track days time but it does get used on the road as an ordinary car a little bit.

Anyone know?

I've got one on my VX220, it's an odyssey 25 (old part no: pc680), the cranking power is about half as much again as the standard battery, in fact I used it to start my 2.5 litre diesel transit and it spun it over a treat. You can mount them in any position you want. Its about 6 kg lighter than the standard battery which for the elise/vx is not ideal as you really dont want to take weight off the front. I've got an isolator switch on it too. The terminals are 6mm thread female and you need to buy the 6mm male posts to fit it.

Cheers, mine's an S2 so the battery is at the back.

Ideal then

[shim]

alternative is Braille

http://www.braillebattery.co.uk/index.php/products...

[A911DOM]

GC8 said:

I use an Odyssey on my light 944 and its been faultless.

Tell us more!

What are you doing with the car - Race / Track / Fast Road?
Pics would be great too!

[legaleagleboy]

I use a tiny Braille battery on my 968 racecar -- frankly have been amazed that it can crank a 3ltr 4 cyl engine.

That tells you that the cranking amps of a gel battery are surprisingly good -- the only down side is that it cannot do it for as long. So if the battery gets flat eg by leaving lights on or you are trying to start a stubborn engine then the gel battery will soon expire. Time for jump leads!

NB so that you know what weight you save -- very approximately a gel battery will weigh in lbs what your std battery weighs in kg -- so about a 60% reduction