Don't forget that you'll want to upgrade the brakes and suspension, you'll need a different rear end as well.

It comes down to having a maybe 90hp 1500 nimble car good for harmless hooligan fun versus a 205hp 1900lb car good for hooligan fun that you can hurt yourself with...........really no wrong answer.

Tom

Yes I see I think it's all depends all goals ect... Seems like a A12/A15 motor is easier to do and manage also cheaper but u will hit a wall with performance ... While the SR20 will require more know how and money but will end up in a better power to weight ratio... If my car came with a motor and tranny I would just stick with the A12 but I rather save up and just put down the 6k or so maybe more for the SR20 swap from the beginning... The info has been great thank u for the help

plenty of untapped power when using an A series with boost!
there are some good threads on now about A series making
serious power and for balance you cant go wrong with the
little A series but also L16 engine is a beast with boost.
Baz on Ozdat in 1970s made 435hp with an L13 with a old
inefficient supercharger on meth & 9000rpm that would be
even heaps of fun today and L16 can rev high with ease.
more capacity is possible and KA24de also is an option
on the L series bottom end and done by plenty nowdays

A stock original Datsun 1200 is not worth anything money wise. Unless you want a daily driver that gets good gas mileage, put a bigger motor in it and make it fun to drive. Anything's possible with a little Dream-ing and a lot of Do-ing.
Go with the KA24DE.