Kevin, When I was faced with this, I just bought the early-style accumulator and was done with it. If you want to update the accumulator, you will have to replace the lines --and it doesn't get you the high-pressure switch; that is a separate installation either on the driver's side of the condenser, or near the bottle itself. The circuit for the high pressure switch is simple. It is on the same loom as the low pressure switch, and you will find a terminating loop in the passenger footwell where the high pressure wiring was later added (you will have to unwrap the wiring slightly to see it). Adding the wiring for it would simply be feeding the wires through the firewall (same as the low pressure) and connecting it to that loom. However, I have found that the high pressure switch is a nice addition, but really unnecessary. Under normal operation, the A/C cycles using the low pressure switch only. The high pressure switch's job is more protection than normal operation: it sits normally closed and will stop the compressor in the event that your high-side pressures get so high that you risk damage to the system, like blowing a hose. If your system is operating properly, with sufficient air is flowing over the condenser, and no restrictions are in the hoses, the high pressure switch won't do anything for the life of your car. Jake Kamphoefner 1063 P.S. - Make sure your evaporator and drain are super-clean also! ----- Original Message ---- From: Kevin Heller <howdyhoho@xxxxxxxxx> To: dmcnews@xxxxxxxxxxxxxxx Sent: Wednesday, July 25, 2007 11:37:41 AM Subject: [DML] upgrading AC accumulator I have an earlier style (non-corvette) type AC accumulator. Since the the system was at atmospheric pressure (open) when I got the car, I'm considering replacing this component in an effort to get the AC in proper working order. Is it possible to update the car to the newer style accumulator? I imagine I'd have to get one of John Hervey's longer spliced line hoses, which is ok because I'm considering replacing the lines anyway (if they prove to have leaks, otherwise the cheaper solution is to just replace the old style accumulator) But what about the high pressure switch and relief valve hub assembly I see on the later VINs? There's a port on the later accumulator for the high pressure switch, but where would the wiring go? (As far as I know I only have wiring for a low pressure switch) Also, how robust are the evaporator and condenser coils in our cars? Should I be worried about replacing them as well or are the hoses and gunk build-up on the coils a bigger issue? Thanks, -Kevin VIN 2234 . [Non-text portions of this message have been removed] To address comments privately to the moderating team, please address: moderators@xxxxxxxxxxx For more info on the list, tech articles, cars for sale see www.dmcnews.com To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnews Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/dmcnews/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/dmcnews/join (Yahoo! ID required) <*> To change settings via email: mailto:dmcnews-digest@xxxxxxxxxxxxxxx mailto:dmcnews-fullfeatured@xxxxxxxxxxxxxxx <*> To unsubscribe from this group, send an email to: dmcnews-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/