OK, we'll split it.

The thing that made up my mind was the reduced side loads on the valves.

As I run short guides, the wear rates are quite high. This means the potential for an engine demolition from valve guide failure/breakage are quite high at 10000+ RPM. The nismo rockers are very good and reliable, but still put substantial side loads on the valves at high speeds. I want the extra reliability.

High RPM speedway mini sprinter engines (A12's) use roller rockers fairly commonly.

I will have to look out for a suitable project car for my grand daughter. A flash 1200 coupe maybe Although by then, anything with petrol burning engines will probably have a health warning as a toxic waste producing device like cigarette packets do now. The taxes to run one by the minute will make international mobile phone bills look cheap

My roller rockers turned up today, [Oooooh, ahhhh, nice] so that was pretty quick. Less than a week. Total cost, delivered, was $777.76 Not cheap, but in 20 years, they will be rare items & sought after in the same way as vintage speed equipment is sought after today.

Feral
Looks like i will be asking you to show me a sample of your pushrods for these rockers when i come to visit. [soon]

Should have something by then for you to see.

And Dattoman you are still special

I just noticed Isky also do an adjustable pushrod. Might not be a bad idea.