Corvette A/C Expansion Valve Differences?

[James W.]

Is there a functional difference between an C2 Corvette A/C expansion valve and C3 expansion valve?


Thanks,

James

[Larry M.]

Re: Corvette A/C Expansion Valve Differences?

No. Capillary tubing length may/will be different. Certainly for the early C3 cars (thru say 1970). Later C3 cars may/will have other differences.

Larry

[Joe L.]

Re: Corvette A/C Expansion Valve Differences?

Is there a functional difference between an C2 Corvette A/C expansion valve and C3 expansion valve?


Thanks,

James

James------

Per your request, the original 1965 expansion valve was GM #5910489. That was discontinued and replaced by GM #5910613 in October, 1968. The latter was discontinued in July, 1983 and replaced by GM #6551445. That valve was discontinued without supersession in 1980 (yes, according to GM it was discontinued even before the valve it replaced!!!).

I do not know what the differences were among the above-referenced valves but they should all be functional for any C2 Corvette. None of these valves was ever specified for a C3. Among all GM car and truck lines, these valves were cataloged only for C2 Corvettes and some Chevrolet/GMC trucks (but not light trucks). Of course, that does not necessarily mean that some other valve part numbers might not work. But, if so, GM never said they would. I believe the C2 valve is available in reproduction or replacement.

[Larry M.]

Re: Corvette A/C Expansion Valve Differences?

James:

I believe the capillary tubing for the early C3 valves is shorter than for the C2. So they cannot be used for your C2. Around 1972-73, the C3 Corvette went from expansion valve to to VIR system (valve in receiver). Totally different expansion valve concept. Then around 1977-78 C3 Corvette went to the orifice tube/cycling clutch system (CCOT) and got rid of the expansion valve altogether..

Larry

[William F.]

Re: Corvette A/C Expansion Valve Differences?

Larry,
Tell me about the orifice tube/cycling system and why it didn't need the expansion valve. I've talkedto you about my '67 facory air car that is having AC problems. If I go with one of the aftermarket systems, for funtionality, operating on cycling as measured by temperature as sold by Old Air products, (not the one that relys on pressures, is an expansion valve still necessary?
Thanks

[Terry M.]

Re: Corvette A/C Expansion Valve Differences?

James:

I believe the capillary tubing for the early C3 valves is shorter than for the C2. So they cannot be used for your C2. Around 1972-73, the C3 Corvette went from expansion valve to to VIR system (valve in receiver). Totally different expansion valve concept. Then around 1977-78 C3 Corvette went to the orifice tube/cycling clutch system (CCOT) and got rid of the expansion valve altogether..

Larry

Larry
1972 Corvette AC system uses an expansion valve. Either 1973 or 1974 began the Valve in Receiver (VIR) I am sure someone more familiar with the 1973-74s will clarify my lack of knowledge of those cars.

[Mark E.]

Re: Corvette A/C Expansion Valve Differences?

That's right Terry- VIR began in 1973 which eliminated a separate expansion valve.

Regarding converting to a cycling system, Dom has cautioned us a couple of times that the A6 isn't suited for continual on/off operation. Maybe he'll chime in...