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JonnyRotten
02-03-2010, 03:10 PM
Do I need a specific battery for a 1960 tr3a.Its a positive ground.Do I just switch the cables on a regular battery?

Mickey Richaud
02-03-2010, 03:19 PM
The battery won't "know" if your car is positive or negative ground. If you want to change the polarity, that's an easy process. But, unless you're going to add a radio or other device, you can stay with the positive ground. The ground strap/cable would go to the positive terminal, and the "hot" cable would hook to the negative.

Twosheds
02-03-2010, 04:09 PM
Only as far as where the posts are located on the battery.

The battery is installed with the posts to the rear so that the hold down will not touch the posts and short them. For a positive ground, the positive post should be on the left side of the car and the negative on the right side. This will allow the cables to be short and not go across the battery.

TR3driver
02-03-2010, 06:45 PM
The battery is installed with the posts to the rear No doubt that is best (although it does leave the clamps somewhat closer to the firewall than I would like). But I drove for upwards of 20 years with the posts at the front edge of the battery, and never had a problem. The main point is be sure to remove the cables & clamps before loosening the clamp.

Worth noting perhaps that the posts are different sizes between positive and negative. For a "proper" conversion, you should probably replace the cables/clamps. Depending on how strong they are, your old clamps may not like being distorted enough to fit the different sized posts.

HerronScott
02-03-2010, 08:25 PM
The battery is installed with the posts to the rear No doubt that is best (although it does leave the clamps somewhat closer to the firewall than I would like). But I drove for upwards of 20 years with the posts at the front edge of the battery, and never had a problem.

The owner's manual for my TR4A (negative ground) shows the posts toward the front near the clamp which is how I always had it installed as well, but if you look at various pictures in the TR4/TR4A workshop manual you can see pictures from early TR4's (can tell from the radiator with the extension) which have the battery installed with the posts to the rear. Those early ones were more than likely positive ground.

Scott