thanks for the replies guys.
I got hold of a place here that crack test engine parts.Will take them to them to test.

I have also interesting news of racing in South Africa in the 70's.
I went to a mechanic that I know well to find out if he knows where I can get sidedrafts.He send me to a guy nearby.I went to him and saw quite alot of Alfas.Obviously he is a Alfa mechanic.
I talked a bit to him and we got talking about the past.He was a mechanic in the 70's for a Datsun racing team.Great!!!!
I asked as much as possible.
He mentioned that in the class they competed those days were a standard production class.No changes were allowed to the cars mechanically and also with brakes, etc.
He said they balanced the internals, lightened the flywheel,used the standard GX cam as they were not allowed to change it and made some kind of box effect in the sump to prevent the oil from flowing to one side when cornering hard and fitted a freeflow exhaust.
Even the Hitachi SU's weren't allowed to be removed.
They replaced the diff with a Datsun utility diff to get higher revs for better torque.
He said they went with one engine for a whole season and to this day that same engine is still driving in that same Datsun as someone's wife's daily driver.Can you believe that.
He says he has more respect for a A12 engine than a A14 due to the internals.
(Sorry A14 guys).
He said they revved to 8000rpm and if on the dyno at 7000 he said the engine was not vibrating if looked at.
One of the events he also mentioned they could not compete in their own class due to twin carburation and they needed to compete in the 1600 class.They did not win the race but he said they could keep up nicely with the 1600 cars.He also mentioned that they once took on a Datsun 510 SSS with the 1600 engine and twin Hitachi SU's.
They managed to pull a small gap on it.Nice for a 1200 hey?

This is what I plan to do.Build a car to the specs of the 70's racing class.