I have seen the method of using a plate.
How hard would it be for an enine builder or and engineering company to cut a slot in the block.

Is it worth my while?

Cheers
Andrew...

You need some way to stop the roller lifters from rotating in the lifter bore, usually this is done by way of a bar / plate with a pivot on each end joining 2 lifters together, to use this system in the A series you would need to either extend the lifter size beyond the bottom of the lifter bore or put a slot in the sides of the lifter bores.

There may be other ways to do it though.

so isnt the less friction worth the added weight?
And what part would be affected by length?

2 reasons I can think of for starters

Have a look at a stock lifter....... not much room there to make it into a roller ( length)

Also you'd be adding alot of weight to make one..... not advisable

I've wondered why it hasn't been tried yet. If it works you'll have an advantage of the ability to run a cam with steeper ramps and I think this would suite the A series well.

there's a few guys on the site that have installed them with success, less chance of bent push rods at high revs

If all goes well ill let you know.
May be a while yet.

Cheers
Andrew..

Never seen it done personally, try it out and you can let me know if its worthwhile...

Has anyone put roller lifters in their datsun?

If not are they worth the money for a race motor?

Cheers
Andrew..