Datsun Roadster Forum-311s.org

I'd like to know how many of us have replaced their valve springs during a head rebuild. Please choose between R16, or U20. And bonus points if their machinist advised it, or if you just did it. Pat

Well, once I got the valve springs out on the bench from my G15 (sorry!) I noticed their free length was all over the place
So, I had my Shop select some which were used but passed the compression test and were identical in free length.

I did replace my springs for two reasons:
1. I did not know the history of the head
2. My head was being rebuilt with a high performance Rebello cam and because my head was being rebuilt by Rebello.

Honestly I would have done it for reason #1 alone.

Thx Greg, I think I'd leave it up to the machine shop, as to what they recommend. I'd change them too, but sometimes older parts are stronger than new ones. Pat

I think that at a minimum, the springs should be checked against the specs for the cam that you are using.

unklpat wrote: Wed Sep 08, 2021 2:56 pm Thx Greg, I think I'd leave it up to the machine shop, as to what they recommend. I'd change them too, but sometimes older parts are stronger than new ones. Pat

That is a good point.

When I am doing a head I do a compression and free length check and replace any not up to spec.

Thanks to all who responded. I'm of the opinion that the machine shop will decide if valve springs should be replaced. We all know that not all new parts are up to the standards of old parts. Pat