What Is The Smallest Battery I Can Run In A Gtr

[Duncan]

Well this isn't really an audio question, but this is the closest forum I can find.

What is the smallest battery (ie CCA) I can run in the GTR. no audio or anything like that I just need enough power to start the car reliably.

eg I would like to use something small like ODYSSEY PC680MJT which is 680cca. Will this be good enough, too small or can I go even smaller

I will go dry cell because the car will only be driven every couple of weeks, and I would like to mount it in the cabin.

And a related wiring question - how many amps does the starter draw, and what other really high currents are drawn in the car (I am thinking fuel pump at around 30A would be next biggest?) How many amps does the standard alternator put out.

This is for the custom wiring etc in a race car.

[turbo_brian]

Completely cold, and only engine, 650cca.

Starter from memory was 120a, but need to check my car.

B.

[infamous_t]

You can use much smaller batteries(motorbike batteries etc), but they will only last a few cranks.

Price to pay for the weight saving.

Once the car is running, the alternator supplies all power to various pieces, so size of battery once running is non issue.

[djr81]

I have a 365 CCA Deka. Works fine. It is an ETX30L It has 26AH

You can get smaller batteries. The main issue is the weight rather than the CCA. A low compression 2.6 isn't hard to turn over.

Duncan, just be careful with the cranking amps listed for dry cells. Some of them use measures other than CCA. Which usually give a higher number. So just make sure you compare apples with apples.

Oh and for info it is in the boot of my R32 & has a Nismo fuel pump making lots of noise. Handles track days etc fine.

Edited July 7, 2008 by djr81

[Bliksem]

I've got an Odyssey PC680 in my Rb30DET and I haven't had any problems in the 7 months I've been running it

[Duncan]

Ok thanks guys looks like I will go with a 680 copy.

$180 over here if anyone else is looking

http://allpurposebatteries.com.au/shop/pro...;products_id=34

anyone got more info on my other questions? what does the starter and other high current thingies draw?

[Kinks]

anyone got more info on my other questions? what does the starter and other high current thingies draw?

starter motors draw volts not amps, dummy..

I'd guess it would be in the region of 100-150 amps. You could get away with a smaller battery for cranking, the reason why we put 550CCA batteries in is for standby current draw (car alarms etc, if you leave the car sitting for 3 weeks) and the motor not starting first go. If using a smaller battery I would put an isolator switch in so you can turn everything off when the car's not being used. A good idea to have one of those in a race car anyway.

As a rough guide for fuses, wiring etc I would follow what the standard loom uses unless you've modified something (car manufacturers are penny-pinchers after all), by the looks of things the main battery wires are 8G and I would not be going any smaller than that (8G is rated for 50A continuous draw). My fuel pump fuse is 15A, and the spec on a Bosch 044 is 12V / 13 amps so the standard wiring would only just handle it. As general wiring practice, the current capacity of the wiring must be higher than the fuse that's installed. If you don't follow this advice I will point and laugh when you get an electrical fault and your wiring melts before the fuse does

[Duncan]

lol good point!

8G doesn't seem that big for the starter, but hey if thats what nissan think its good enough for me. from looking at the main loom its only starter/alternator/battery that run beefy cables. Looks like nothing else draws more than 20a like fuel pumps.