power steering valve question

[Craig O.]

would the 67 power steering valve be the sams as a 72 ?

[Joe L.]

Re: power steering valve question

would the 67 power steering valve be the sams as a 72 ?

Craig-----


Yes, they are the same. Also note that original valves for 63-74 had no hose guide bracket as part of the assembly. Later PRODUCTION as well as later SERVICE valves for 63+ Corvettes do have such a bracket.

[Jim S.]

Re: power steering valve question

Myresearch into the history of the control valve manufactured by Saginaw SteeringGear Division, GMC, led me to the information that there were two control valves. One in use from 1963 through 1975, the other was used from around 1976through 1982. The difference was aninternal valve spring. The early valveused a 55 lb spring, the later valve used a 40 lb spring. The different loads were specified with thesprings compressed to a height of 0.38 inch.

Thereason that the spring was changed from 55 to 40 lbs was most likely to makethe valve more responsive and probably to compensate for larger cross-sectionlow pressure radial tires. None of theCorvette supplier catalogues that I have reviewed makes any reference to thetwo different control valves. My guessis that if you have a new or rebuilt control valve, you probably have a 40 lbspring.

At one point, Vette Brakes & Products Inc would build you a control valve with a 55 lb spring. I never received any feedback as to people requesting valves with heavier springs and whether or not there was improved steering feel with the heavier spring.

BTW, if you are concerned with the valve looking correct, there were several cosmetic changes:
1. From two 12 point bolts to hex head bolts around late 1979 or 1980.
2. The letter "C" was removed from the valve end cap around 1978.
3. The first hose guide bracket was added around the 1974 model year. The bracket extended past the valve end cap. The bracket "ears" were bent forward away from the valve.

4. A redesigned guide bracket was introduced 1975. The bracket was shorter (even with the end cap.) The ears were bent back.

Jim

[Ron G.]

Re: power steering valve question

Just an FYI - If you are having your car judged, note that original dust caps on the end of the p/s valve has the letter X indented into the cap. If it has the letter C or no letter at all, then it is a replacement.

[John H.]

Re: power steering valve question

Myresearch into the history of the control valve manufactured by Saginaw SteeringGear Division, GMC, led me to the information that there were two control valves. One in use from 1963 through 1975, the other was used from around 1976through 1982. The difference was aninternal valve spring. The early valveused a 55 lb spring, the later valve used a 40 lb spring. The different loads were specified with thesprings compressed to a height of 0.38 inch.

Thereason that the spring was changed from 55 to 40 lbs was most likely to makethe valve more responsive and probably to compensate for larger cross-sectionlow pressure radial tires. None of theCorvette supplier catalogues that I have reviewed makes any reference to thetwo different control valves. My guessis that if you have a new or rebuilt control valve, you probably have a 40 lbspring.

At one point, Vette Brakes & Products Inc would build you a control valve with a 55 lb spring. I never received any feedback as to people requesting valves with heavier springs and whether or not there was improved steering feel with the heavier spring.

Jim -

From the 1967 Chassis Overhaul Manual, page 9-25:

"Note: Corvette valve incorporates a 55-lb. centering spring which is physically but not functionally interchangeable with the Chevy II spring, which is a 30-lb. spring. The Corvette valve incorporating this spring is identified by an "X" stamped on the dust cover."

The last year for the Chevy II PSCV (with the "C"-stamped dust cover) was 1967; the new '68 used an integral power steering gear.