I swear the silver cap on the left on my radiator is correct for a 70 GS Stage 1 w/AC. However everyone tells me the one the the right with the blue stripe is correct. I thought both were correct for 70. Just depends on your application. However it seems not to fit on my CF tank from 1969. The cap with the blue stripe doesn’t seem to want to sit down on the radiator as I try to apply pressure and turn. It has a stiff cardboard like gasket under the cap and the “do not open blue striped” tag on top spins as it try to apply pressure to turn the cap. Plus the inner gasket is half as thick. just doesn’t seem robust to me. or am I just overthinking this? Thoughts? underside of blue striped version
The blue stripe is correct...the repros can be....difficult....to install the first time or two. There is some effort required to get the cap to stretch on a bit.
I had an issue with the car seemingly running warmer with the smooth edged one from CARS and switched back to their scalloped edged cap, thereby resolving the issue. Odd, I know. As Adam mentions: they fight you most of the way getting them on/off the first few times. Long story, short - blue stripe is what you want for your car.
The radiator cap on the 1970 GSX in the Sept 1970 issue of Road Test magazine doesn't match the original on my GSX. So apparently there were at least two styles used. Both had smooth edges.