just use a really good quality oil and you should be right. In an offroader that regularaly get revved to bounce which is about 9500 rpm we havnt had any problems.

That info would have been handy Yesterday. Ive got it all together now!!
Hey thanks anyway.
I`ll put it in the memory bank.... and probably will recall it when the motor spins a bearing!!!!

apparently its a great idea to increase the size of the oil galleries to the main bearings if you plan on regularly exceeding 7000 rpm. The galleries dont flow enough for reliable revving. This came from a guy running an a12 in a b310 as a track car, 100 hp at the wheels and normal gear change at 9000 rpm.

Thanks,
I emailed another member to get the spring rate requirements and Ive found some great behive shaped springs that use smaller diameter retainers and work with the datsun collets.

Should be good up to 9,000. Im only going to turn my a12 to high 7`s maybe 8k so all good.

Stay away from the brand performance springs (or is it competition springs?) Either way they are crap. My local cam guru wont even sell them anymore.

Thanks DD,
Yes, all stock components. Do you know what the GX set presures are?
The two sets i have have been taken from other makes of engine so i dont have a referance.

I have mesured them and a standard A12 set:

Standard- 25lb seat and 100lb over the nose (checked at 9mm lift)
Set 1 - 40lb seat and 150lb over the nose
Set 2 - 100lb seat and 230lb over the nose

I would need to know where the GX set fit in comparison.

It depends on the weight of your valves, pushrods and lifters.

With stock components, the GX dual valve springs are marginal for 8000 RPM use. So go stronger.

Im trying to find out the valve spring pressure required to prevent valve float at 8,000. I have two sets to choose from and only want to run the heavier set if i have to. I`ll be running about 15psi boost aswell so this could add another 15 to 20lb to the requirement also. Standard cam at this stage too.

Seat pressure?
over the nose pressure?

Can anyone help?
Thanks