Yep ive made two or three of them and you end up at 3~3.5L it’s not enough.

You could make one with more capacity. And they can be a ball ach to get the starter to fit.

For a 7 do it once do it right = Raceline .

Other options.

Neil Dunne does one, they love him on Fb.
Tigger racing, not ideal. Do some research.
Gbs/Kitspares, same sort of thing as Neil Dunes’s but more money..

re the oil pump. Again do your research and make your own mind up but, for 300bhp I would stick with a clean well seasoned Oem pump and over 400 I would go for external pump.