Parts interchange question for 69 & 70

[Steve G.]

I have a '70 LS5 with AC and automatic. I am looking at a radiator for sale from a '69 427. Not sure if the car had ac or not. And I cannot find any tags on the radiator. Anyone know if the radiators are interchangeable and / or date coded? See pictures below.

Also was looking to buy a blower motor ass'y with cooling tube for my ac car. I found one from a '74. it has the tube and resistor still intact. Would that be correct and are they date coded?

Is a master cylinder from a '70 non-power brake car same as for a '70 power brake car? thanks, Steve

[Jim T.]

Re: Parts interchange question for 69 & 70

Steve the master cylinders may look the same however the power brake master cylinder will have bigger bore and pistons. The power brake master bore is as I remember is 1 1/8 inch and the manual is 1 inch.

[Joe L.]

Re: Parts interchange question for 69 & 70

I have a '70 LS5 with AC and automatic. I am looking at a radiator for sale from a '69 427. Not sure if the car had ac or not. And I cannot find any tags on the radiator. Anyone know if the radiators are interchangeable and / or date coded? See pictures below.

Also was looking to buy a blower motor ass'y with cooling tube for my ac car. I found one from a '74. it has the tube and resistor still intact. Would that be correct and are they date coded?

Is a master cylinder from a '70 non-power brake car same as for a '70 power brake car? thanks, Steve

Steve-----


It does not matter if the 1969 had C-60, or not. However, it does matter if it had M-40. If it did have M-40, then the radiator is exactly the same as your 1970. The thing to look for is whether it has the oil cooler fittings on the right side tank. M-40 applications require the oil cooler.

By the way, the radiator you require was GM #3019190. This radiator was not only the GM original radiator for 1969-1972 Corvette big blocks with M-40 (except 1969 L-88 and 1971 ZR-2), it was also the only SERVICE radiator available for both M-40 and non M-40 1969-72 Corvette big blocks since about 1973. So, even if the 1969 donor is a 4 speed, it's still possible that it could have a correct radiator for your application IF the radiator was replaced at some time with a GM piece.

The blower motor assemblies from a 1969 and 1974 Corvette with C-60 are functionally interchangeable. However, the original part numbers were different. Also, the motor assemblies ARE dated.

Addendum----

By the way, the radiator in your photos does not appear to have the oil cooler fittings. However, I can't see it all that clearly.

[Joe L.]

Re: Parts interchange question for 69 & 70

Steve the master cylinders may look the same however the power brake master cylinder will have bigger bore and pistons. The power brake master bore is as I remember is 1 1/8 inch and the manual is 1 inch.

Jim------


Yes. Also, the standard brake master cylinder will have casting number 5455509, a "DC" stamping, and bleeder valves. A power brake master cylinder will have casting number 5460346, a "PG" stamping, and bleeder valves.

[Steve G.]

Re: Parts interchange question for 69 & 70

Thanks for all the info. I think I'll hold off on the blower motor until I can find one that is correct.

Regarding the master cylinder - is the master cylinder CAP interchangeable between a power brake setup vs manual setup? Any distinguishing marks between them that would make it not 'correct' to swap one with another? Steve

[Joe L.]

Re: Parts interchange question for 69 & 70

Thanks for all the info. I think I'll hold off on the blower motor until I can find one that is correct.

Regarding the master cylinder - is the master cylinder CAP interchangeable between a power brake setup vs manual setup? Any distinguishing marks between them that would make it not 'correct' to swap one with another? Steve

Steve------


The non-power and power brake master cylinder caps are absolutely identical but only for caps manufactured within certain time periods. In other words and for example, an original 1970 non-power cap is the same as an original 1970 power brake cap. However, there were slight changes in the configuration of the cap as well as changes in the script stamped on the "domes" of the cap over time. So, while all 1967 through 1982 caps are interchangeable on a functional basis, they are not all identical.

[Patrick H.]

Re: Parts interchange question for 69 & 70

Addendum----

By the way, the radiator in your photos does not appear to have the oil cooler fittings. However, I can't see it all that clearly.

In addition, the rad looks a bit "crusty."
He will probably have to consider a new core from DeWitts and have the radiator restored.

Patrick

[Jim T.]

Re: Parts interchange question for 69 & 70

Reference your radiator question, the radiator shown appears to not have a location for the radiator cap. My 70 350/300 with air and turbo 400 has automatic trans connections on the radiator and radiator cap located on the radiator and is the original radiator still in use.

[Joe L.]

Re: Parts interchange question for 69 & 70

Reference your radiator question, the radiator shown appears to not have a location for the radiator cap. My 70 350/300 with air and turbo 400 has automatic trans connections on the radiator and radiator cap located on the radiator and is the original radiator still in use.

Jim-----


Small blocks with copper/brass radiator used an integral cap on the right side tank. However, this car is a big block. ALL 1969-72 big blocks used an external supply tank and the radiators used had no provisions for an integral cap.