Battery Suggestions?

[Seymour Snerd]

...If it doesn't work out, I'll pull it out, ....

Nice install!

The MSD box is also bright red and ugly!

If it comes to that, another good place for the MSD box is right behind the firewall hatch in back of the driver's seat. Presumably it gets cooling there, but OTOH there are radiator lines nearby and an engine just a little to the rear... but the road draft should help. I did notice on Steve C's car P2125 he took the bottom off the MSD box, I assume for cooling.

 

[Ron R.]

Alan,

Thanks.

I thought about that spot, and even putting it under the seats. In the spot where I have it, as long as the lid is off, I can make any adjustments (rev limits etc) pretty easily. And, the hookups to the battery will be REALLY easy.

Mostly, I just didn't want to look at it (agreed, bright red and ugly).

Taking the bottom off is something I hadn't thought of. I'll have to check into that. Thanks for the heads-up.

 

[Seymour Snerd]

. the hookups to the battery will be REALLY easy.

That's for sure! Plus your IGN and Tach wires are right there. Stringing the harness across the firewall and having to extend some of the wires was no fun. But it's done so now I can laugh about it.

 

[Ron R.]

That's for sure! Plus your IGN and Tach wires are right there. Stringing the harness across the firewall and having to extend some of the wires was no fun. But it's done so now I can laugh about it.

Exactly.

Everything comes out of the harness right there.

 

[Kevin L]

... and even putting it under the seats.

I had mine there, in the back of the passenger seat (not my choice, bought the car that way) and it was less than optimal. The good news is that it added lumbar support, the bad news was that it was a LOT of lumbar support and it was solid rather than like a balloon. Needless to say, I don't recommend it.

Mine is now in the compartment behind the firewall hatch and I like it much better there. That said, I sure like your solution.

Kevin

 

[Ron R.]

Kevin,

My MSD unit (digital 6al) has a few dials for adjusting the rev limiter, etc. I wanted the dials to be easy to see and adjust.

When I put together my Kirkham, I mounted a Digital 6 under the dash. It had similar dials etc for adjustment, but I could never see the blasted things to adjust them!! Between the general lack of light and my near-sightedness, I literally spent hours swearing under my breath while laying upside down in the passenger compartment trying to make changes.

Needless to say, I wanted to be able to see what I was doing this time.

Of course, I may cook the thing in the end. If so, I'll be sure to post it as a lesson learned.

 

[Rich E.]

Ron,

Just an idea but if your worried about cooking the MSD how about one of these. Not sure if the MKI and MKII's have the same raised box cover. If they do you could mount 1 underneath with a couple of vent holes on the side of the lid for circulation.

 

[Jack Houpe]

I have a electromotive TEC2 EFI computer behind my passenger seat under that little hatch and on the drivers side I run a MSD DIS4 unit to power the coils, both have been in those little spaces since day one and I have never had a problem and many of miles on the car.

Hey Rich, I am going to waterjet out some of those door handle pulls and a couple of pull rings for the front. PM me your address.

 

[Mark]

Anyone know which battery out there has the highestt CCA rating and still will fit into the battery compartment of the car? I have a S1200 right now and that isn't giving quite enough umph to crank the FE motor easily.

Thanx
Mark

 

[Seymour Snerd]

Here's the research I did at the time:

Battery Box Dimensions and Battery Choice

9.5” long, 7” wide, 6” high with an additional 1.25” high in the cover.
Matching sizes are (mm, then inches)

BCI# L W H L W H
42 243 173 173 9 5/16 6 13/16 6 13/16
57 205 183 177 8 1/16 7 3/16 6 15/16
75 230 179 196 9 1/16 7 1/16 7 11/16
90 246 175 175 9 11/16 6 7/8 6 7/8
96R 242 173 175 9 9/16 6 13/16 6 7/8

But that S1200 puts out 750A .....about 12 horsepower. You might check your cabling by measuring the voltage across the battery, and then across the starter, both while you're cranking. If they're different by more than a few tenths then you have a cabling or grounding problem. Also, are you sure the battery is fully charged? FWIW I bought a charger with a specific AGM setting when I got my S1200.

Up above DaveM says a 96R fits perfectly with no space.

 

[Seymour Snerd]

<deleted>

 

[Mark]

Has anyone tried an Optima Group size 35.? Just went out and measured and it looks like it should fit.

 

[Neal]

I've run an Odyssey PC680 for the past five years. Super compact and enough cranking power for my muffin warmer. Just be sure to use a battery tender during downtime.

 

[Steve C]

I'm using an Odyssey too.

Great battery!

Steve P2125 (cranking an FE)

 

[Ron R.]

My motor goes in on tuesday. Very healthy C/R (11.95:1) 393ci, 600 bhp/555ftlbs torque.

Ill let everyone know if the Odyssey has any problems turning her over.

 

[Mark]

The Continental 96R-72 is a perfect fit for the battery container in the MKII (to include once the cover is on). It has the following specs:

CA: 950
CCA: 800
Res Cap: 135
Warranty: 2 years
Cost: 99.99 with $12 core fee

I drove over and picked one up today at the Continental distribution office in Dallas. The salesman, Edward, was very helpful and proactive in trying to find the highest output battery that fit into the GT40 battery container. Continental's phone number is: 800-442-0081.

Mark

 

[Lance]

This thread has come at a convenient time as I'm looking at this issue just now.

For reasons of space, redundancy and just to be different, I'm using two batteries wired in parallel. From the discussions, it seems that two Odyssey PC680's should be more than enough for the same weight as a 'normal' battery. What are your thoughts?

Has anyone else gone with two batteries?

Cheers,

Lance

 

[Ron R.]

Just a little follow-up.

As a reminder, I went with the Odyssey PC680, a rather small battery that allows me to fit the MSD in the battery box.

The battery has held up like a champ to numerous successive starts during engine tuning.

It has failed to start the car once. After a 50 mild drive, in stop and go traffic with the aircon on etc, all seemed well and good. When it was time to return, I hopped into the car, turned the key, and imediately noticed that the ignition light was rather dim. Needles to say, the starter wouldn't turn over.

What I think happened, was that that the cooling fans (on a thermostat that turns them on, but can't be overridden to turn them off) came on, and continued to run for an extended period, despite that fact that the motor wasn't running. The keys were out of the car, and maybe the fans won't run without them...I'll have to test that to make sure. Otherwise, perhaps all the time I spend idling prevented the charging system from keeping up.

I haven't had any problems since, and will be installing an electrical kill switch that should preclude this from possibly happening again.

If it turns out that the fans can't run without the key, I'll probably go to a larger battery, like the 97-R.

 

[Seymour Snerd]

Ron --

I just looked at the schematic, and the radiator fans should not run when the iginition is off. In addition, I confirmed that with an experiment on P2160: shorted my radiator temp sensor to simulate "hot water" and although it turns the fans on with ignition on, turning ignition off turns the fans off.

I'm nearly certain, based on the schematic, that the only things on the car that should run without ignition on are lights and horn.

Which gauge do you have, ammeter or voltmeter? I ask because one possibility is that in your 50 mile s&g trip the alternator was not keeping up with the fans and thus while you were driving the battery was discharging. Since you have a later car you probably have the big 5-bladed fans, and those things draw 40A. It could have discharged completely while the alternator was keeping the engine running. With an ammeter you would have seen this by observing the ammeter was constantly negative while you were driving. With a voltmeter you would see a constant value of 12 or below while driving. The point being, before you invest in a bigger battery you might want to make sure your alternator is doing its job on hot days at low speeds. If it's not, a bigger battery will do the same thing, but just after a longer drive.

 

[Ron R.]

Alan,

Thanks. I'll be at work a while yet, but I'll look at the schematic when I get home. I assume you're right, which means that I'll be shoping for a bigger battery.

Not that I drive in stop and go traffic a lot, but I don't want to be afraid of it either.