Just purchased a 90' 240 about a month ago and found out it had a blown head gasket. My question for anyone here is whether or not its worth replacing or should I just step up to the SR20. Any help is appreciated right now, thanks guys.

 

The 90's engine is a TURD, at least pick up a dual cam KA, or if you can afford the SR go for it, it's a pretty easy swap.

 

Just like RK said...throw out the SOHC and toss in a DOHC.

If ya got the money for it, go RB/SR/CA

 

the sohc and dohc are both pretty decent if you plan to do a bit more of a custom turbo. the Dohc has higher compression & won't take as much boost as a Sohc (that has lower compression) but the Dohc puts out more power.
As you'll see if you read in the engine fourms a bit, there's alot of contraversy over whether the sr is just tossing money at the car w/ no real gains when turbo'ed.
do some reading. ask some ppl that are smart- ask some mechanics, not just us gear heads. and then decide for yourself. we all have our preferences (i'm keepin my KA and going to custom turbo, but mine's low-mileage.) learn enough to make your own.