Nissan 240sx engine choice

[Racerfanny]

Any rb is a good choice the rb20det we see you good for around 500bhp but runs well around 400bhp.
The Rb25det offers a mass of max speeding aftermarket parts due to more people owning the Skylines with these engines fitted,the egine is good for just over 1000bhp.
The rb26dett can see well over 1000bhp but an expensive engine due to demand.
The sr20det is another good option and one to go for if you do no want the really high bhp figures this engine can see big bhp but runs at its best around 400+bhp there are examples of it running quite abit higher but suffers alot,but overall a good high reving engine and a popular pick.
Other engine would be the Nissan VG and VQ 30 engines also the 1 and 2jz Toyota engines.

[PapaSmurf2k3]

RB would be a good choice for 500+
KAs would have more turbo lag and reliability issues passed 500.

[SoundEfx]

Another option is to go LS power because the parts for those engine are more readily available.
Personally, I can't though. LS in a 240 just sounds weird.....lol. But it is still an option.