si Banker

My 87 coupe is a low milage car and this weekend I decided to check the battery level and condition, it had been about two months since the 15k service. There were signs of some minor leakage so I removed the Porsche battery, (it loooks like it belongs in a large truck), and have decided to replace it with a Optima sealed battery. Has anyone had any luck or exprience with them? Cranking amps appear to be comparable.

In order to remove the battery and clean the area with baking soda I also removed the ac blower motor. I was supprised to see how small the fan motor was and also the opening through which it operated. No wonder the ac is so bad. The air is drawn in from behind the front bumper then forced through a 4 inch by 6 inch hole on to the ac condenser.

It seams there should be room for improvement somewhere.

Richard C2S

I agree. I will be doing the same thing in another few weeks, not because the incredibly large and heavy Interstate is bad, it isn't. Just to clean around and beneath it. I have some limited experience with Optima. I put one in my 993 several months ago when the conventional battery died (3 years old). I haven't noticed any negatives, so I am seriously thinking of putting one into the SC.

Clipboard

Hi
I did the Optima red top in my 83 SC and it's fantastic. The install was easy - getting that truck battery out was the hardest part. After cleaning out the crud - you cannot get it all as so much builds up under that shelf, I painted the hell out of the area. Install was a breeze. I had to replace the now-too-short ground cable with a longer one from an auto supply store - it was much higher quality (and encased in clear plastic) than what came out. Battery hold-down is an issue as the way the original clamps in is not compatible with an Optima, so I also picked up a 'universal' hold-down bracket and two J-bolts. I used these to put the bracket on the'long' way instead of across the new battery. Total was about US$125 for parts and battery. Two things you'll notice: no fumes!!! and therefore no acid vapour deposition in the boot or on the fuse/relay panel electrics; great battery charge hold. I sometimes don't run the car for a month and it cranks right up. The weight may be coming off the front, but it's still gone!!
Good luck
john

si Banker

As I has stated before, I had concerns with the possibility of the battery in my 87 911 leaking . Yesterday I replaced the original battery, brand name Moll and which had a Porsche part number on it, with a new Optima. It has more cold cranking amps, (980@32F), than the oem. It works great and there is less chance of leakage since it is sealed.

We used .375 6061 plate and machined a recess which the new battery sits in and is held by aluminum bracket. The plate uses the oem rear and forward mounts to hold it in place.

A added benefit is the savings of 14 pounds.

I still have questions about the ac

Clipboard

Howdy,
I must assume that the 87 has a better stock a/c system than my 83 did - mines alllll gone now and I don't miss it. IIRC, in the Florida street shop, they: a) replaced compressors with rotary ones (Hitachi??), replaced the lines and dryer, and added a THIRD condensor under the main floor. Don't know if this helps.
Good luck
john

si Banker

I lived in Boca and from 1983 to 1987 drove a 1982 sc as a daily driver and never had a complaint about the ac. I had a front condenser and a big York compressor which you could feel pull on the motor each time it kicked in.

I now live in Texas near Fort Worth and have reentered the Porsche world after a 16 year absence and bought a 1987 coupe but it can't keep up with the heat; if you leave the car parked in the sun for a few hours and try and cool it down it takes for ever. If you are parked in a garage and drive out into the heat it holds up pretty well , but the hot months are not here yet! Southeast Florida temps seldom exceeded 95 degrees but Texas is a whole different deal.

I thought the holes through which the front blower operates were to small and restrictive. I have thought about adding the condenser in the rear fender and changing the dryer and hoses. I read the different posts regarding the different opinions about 911 ac and my conclusion is to just have an extra car for those months you need the extra ac

wwest

To increase A/C performance I would buy about six of the most robust and powerful 12 volt muffin fans used to cool PCs. Mount them above the condensor on the engine lid with airflow toward the engine compartment. If you don't already have a whaletail or teatray then add one to hide the fans.

scottb

If you really want decent a/c in an 80s 911, you need to add condenser surface. There are two ways that seem to work. The first (which is what I did) is to remove the washer bottle and vapor recovery tank in the front left fender, and add a condenser/fan assembly. The other alternative is to add the Performance Aire condenser underneath the car. I also added a ProCooler. My car gives me mid-30s vent temps on scorching Southern California days.