Common practice is to move to the frunk or get an odyssey pc680 and lay it on its side.

Generally you want to reduce weight or move weight forward, of which you accomplish neither by moving to the trunk.

 

Dude,


Big 2nd for installing a smaller battery in the same location. PC680 is what I used and it lasted 5-1/2 years before I recently replaced it with another PC680.





- Chester

 

My friend uses a motorcycle battery and moved it to the right side of the frunk. Then he cut out the battery tray and other newly useless metal. Should see the space in the engine compartment!

 

Where do we start?
Why do you want to do this? Moving weight to the back is not good for our short wheelbase cars, especially if you are using a lead/acid battery.

If you need space, move the battery to the frunk (front trunk). Like the other guys said, you can also place a small dry cell on its side and save some wiring.

If you want to know what is on the other side of the felt trunk panel, just take it off and look. If you are dead set on trunk mounting you would have to take the panels off to get access to bare metal anyways.

I have my battery in the frunk and there is still room for a full sized spare. I made my own battery mount to allow for clearance.

Always look on the other side of a panel before you drill. And remember to floss.

 

I vote for not moving weight forward, but just reducing the battery weight with an AGM (motorcycle/snowmobile battery). I've had my 9lb battery in the stock location for 15 months and about 20,000 miles now with no troubles. This does influence overall vehicle balance for/aft. I personally like a little rear bias myself. Better for traction both stopping and going.

 

So the reason I will be moving the battery is because of how cluttered the engine bay is. That, and the previous owner bought too big of a battery and the terminals would be shorting on the intercooler if it weren't for rolls of electical tape shielding the terminals. I thought about moving it to the front, but there is already 4 gauge wiring going to the trunk because the previous owner installed a sub and amp but later removed both of them. I checked underneath the carpeting and peeked underneath the car to see if i could potentially drill through something accidentally but i figured it wasn't a bad idea to ask as well.

 

I have a PC680 on it's side in the stock location too and it has worked out great so far. The only downside which hasn't been a problem really is that the intercooler sags on that side a bit without the 2 mounting points from the battery tray. I've been meaning to make a bracket from the tray to hold it up there but haven't yet.

-Mike

 

I noticed that issue on a fellow owners SC the other day. NA no problem.

Yes, forget the oversized battery and just get a small light AGM in the stock location. I had to make a custom bracket, but it wasn't too hard. Save 30lbs of dead weight. I think i paid about $100 for my 9lb unit.

Edit:

I was wrong, only $67! My exact battery. Saves on cable weight, and power loss from cable length too.

http://www.amazon.com/gp/aw/d/B002ZEQG8E/ref=mp_s_a_1_1?qid=1403231148&sr=8-1

Only downside of a smaller battery (10Ah) - you can more easily drain the battery by accident (leaving lights on, running radio, etc).

 

Only downside of a smaller battery (10Ah) - you can more easily drain the battery by accident (leaving lights on, running radio, etc).

Or cold weather.
If you live somewhere that gets much below freezing on a regular basis you will regret a small battery. Park your car for the weekend and try to start it mon morning in -20 f and nada.
I ended up getting a solar trickle charger permanently mounted in my car. It was enough to fix the problem as long as there was enough sun during the day.

 

alright, i'll look into it. thanks for the help you guys.

 

Hmm, you've experienced that with a modern AGM like the Odyssey or the one I linked?

I can't speak from experience, but cold cranking amps are supposed to be quite good with something like an ETX 12 or 14. I've certainly never had any issue cranking, even in sub freezing weather. Only like 20F though, no -20F.

 

Yep, two different 680s.
When I got my first one it was great the first summer, that winter it was fine till I parked it over the weekend. If combined with a cold snap it wouldn't have enough to fire Monday morning. I tested for draws and everything looked good.
I limped it through till the next fall and it had gotten much weaker so I ordered a new one. Same issue. It was fine till it got really cold. Even just parked for a couple days in below zero temps and it wouldn't have enough to crank the cold motor.
The trickle charger helped as long as there was plenty of sun.
During the winter we do have some weeks or even good portions of months that sink well below zero at night.

 

interesting.

my ETX12 says 180CCA on its side. However the batteries (my brand specifically) gets many comments as being underrated for CCAs. Honestly I had a better impression of my battery brand than the Odyssey batts, hence why I bought mine.

The other thing is, I'm pretty sure my battery is suited for snow mobile use. So I'm confused.

Maybe something was draining your batteries?

 

... I'm pretty sure my battery is suited for snow mobile use. So I'm confused.

A snowmobile does not usually have a 1600cc four stroke engine.

 

180cca seems low for a mk1. 500cca seems more of what it needs. What does Toyota say the car needs?

 

don't get the PC680..
The first cold day in November with my PC680 and my car would not crank.
Most of the guys running these small batteries live in SoCal where it's usually above freezing, or they track their cars. If you DD the car, get a normal reliable AGM rated battery.

 

A 50 series optima or similar style would be smaller and mountable on its side as well as a bit lighter for everyday...
I've seen somewhere mk1's ask for 350ca ... I could be wrong though :/

 

Has anyone looked into using a LiFePO4 battery in an MR2?

For $148 you can get a 14Ah, 210cca battery that weighs 1.6lb, but they don't recommend using them below 0deg C.

 

My batt has started reliably in 20F weather. I have done something like 5min of combined cranking for compression testing, and it still started reliably afterward. Do your own research, but I've heard good things about my batt brand, and it has provided almost 18months of trouble free service. Even had it drained once from leaving the lights on.

Research it, use a larger model perhaps if you need it. My point about snowmobiles is that the batts should be fine in the cold.

 

Research it, use a larger model perhaps if you need it. My point about snowmobiles is that the batts should be fine in the cold.

They will handle the cold just as well as any battery. All batteries loose cranking amps the colder it gets. These just have a whole lot less to start out with.
I also suspect it has a big effect on the draw. Even though my car had an acceptable amount of draw the basics like clock, ECU and the couple other little things are still going to drain the battery a lot faster at -15 than at 70. The amount of power required to crank the motor is also much greater since oil is thicker and it takes a lot more effort to spin it.

I think it's the combination of all these things that makes a big overall difference.