Doug's A/C System, R&D/Build Thread Options

[dlee6204]

I thought I would document my A/C adventure in the hopes that it would be a good reference for anyone else considering A/C. I’ll first touch base on the stock system and on custom options and then start building my own system to start testing on. I’ve working on a few systems before but I'm sure there is someone that knows more than me so don't be shy sharing or adding anything. (IMG:style_emoticons/default/smile.gif)


To begin things off here is one of the better overviews of an A/C system. Follow the link and you can see a breakdown of the whole system.


http://www.movacs.com/How%20it%20works/index.html





Anytime I refer to the stock system I will be referring to the dealer installed VPC system mostly because the only A/C cars I had came with this system and I have plenty of parts around.

I also borrowed some photos off this site so if I used any of yours... Thanks. (IMG:style_emoticons/default/smile.gif)


Compressor:

The compressor that came on dealer installed A/C systems was a York Piston style compressor that had a capacity of 6 cubic inches/Rev. From what I could find it used about 7-10 horsepower from the engine. You can still use this compressor however there are better, more efficient options out there. When choosing a new compressor it is a good idea to find one with a similar capacity. In this case going bigger does not mean better. An A/C system works as a whole unit and if you dramatically change one aspect of it, you will likely see negatives effects elsewhere. Choosing a compressor that’s too big will overwork the system, yielding no little to no benefit, and create a not-as-efficient system. During my search I looked mostly at Sanden style compressors so that's what I'll be referring to in my build. Using a modern compressor like the Sanden will only use about 3-4 hp from the engine. I have heard quite a few people use the Sanden 508 compressor with good results. It has an approximate displacement of 8 cubic inches/rev, which IMO is slightly more than I'd like to make a jump to. I'm not saying it wouldn't work, it obviously works, however I think I will get slightly better results and pressures using the Sanden 507 (approx. 7 cubic inches/rev). The SD507 is also slightly smaller in size than the 508.

Here is a picture of the York Compressor


A side by side with the SD507





And here is a SD508

[zambezi]

Here are some of my condensor mountings. I am running the DPD system because that is how my car was bought new. I am not driving the car yet (still waiting for paint) but it is fully functional and have got 40 degrees out of the vents, and that is with an unsealed cabin with no seals anywhere.



this was the before picture. What a hack job that was done at the dealerships huh!!



Here is how I braced and cleaned up the opening.



Here it is with the condensor test fit with the new SPAL cooling fan. It cover a much greater area and will flow a ton more air.



The original fan for comparison. Even the squirrel cage fan that comes with the VPC setup flows better than this.

I will have to get out to the shop and take some pics of the final setup showing hose routing and drier location. This is going to be a good thread and should be a great place for all the A/C configurations to be posted. I am curious how your smog pulley system will hold up and how much it is offset towards the front of the car. There is not a lot of room forward towards the firewall. My pulley works good but it is still very close. I would have more room if I was not running the factory sound pad (with a layer of dynamat extreme behind it as well).

I will try and get more pics loaded up in a day or two of the rest of it.

JIM

[mtburman]

It's important to watch spacing on the condenser enclosure/fan if you are going to retain the spare tire mounting on top of the cone. Too far back makes it difficult to set/remove tire.