120y is 1200cc engine

it's illegal if u don't register it at jpj, FYI, a lot of ppl say cannot register because 1.2 upgrade to 1.8 or 2.0 is more than 25% cubic capacity set by jpj, but this is totally wrong, i've seen 120y with CA18 and SR20 successfully registered, but the runner fees won't be cheap, prepare RM1300 to 1500 just for the puspakom inspection and jpj registration.

TS, if u have around or more than 6k budget, u can opt for CA18det, budget = or more than 9k go for SR20det, google if u don't know what engines they are. 

if u have only 4k then below is doable (GA16de sentra engine + datsun 210 gearbox or other car's gearbox that can fit.  i don't know whether they sell halfcuts of the Nissan Serena GA16de in Malaysia or not, if u can find one, then it's a RWD transmission):

http://sr20nation.com/ga16forum/showthread...sion-for-GA16DE
if u don't want nissan engine, then the toyota 16valve from the AE86 can fit, it's cheap nowadays but it's very old

if u don't care about FC or maintenance, u can even put in a Mazda B13 Rotary engine, which is MAD!

but most important of all, like vinothrao84 said, make sure you strengthen your chassis first, or else, u'll split your car in half if too much power

this kind of conversions are not hard, u need to have lot's of spare cash, and lots of patience, and the result is very rewarding.  You probably can give your 120y to your children and they can still use it as a daily drive after your project is completed

keep it classic bro, you are fortunate u have a pristine 120y, i still looking for 1 to keep.

don't do too much modification, overhaul the engine, make it look like just came out from the factory.

Agree with AlexLee277. Restore it to mint condition first.
Reliable car thou.

do you even know what you're saying?

converting to 1.8L or 2.0L is ILLEGAL according to JPJ. not just engine need to be checked, the braking and suspension system need to be properly do up especially on such a light chassis. using runner? just wait till next round of JPJ checks, let see how many times you need to fork out money to check.

CA18DET? parts already out of production more than 5 years. no more parts. people are dumping this engine for SR20DET. there are other do-able engines such as SR16VE or nissan vanette A15 (plug and play).

4AGE 16V is cheap? the halfcut itself costs more than RM5k. engine is not old compared to 120y's stock engine and CA18DET. but sourcing for parts will kill you as people are jacking up AE86 part prices.

B13 rotary is good also, know one fella did it. power is good and car's body weight is balanced.

For RWD, you will not split your car in half. only FWD will.

parts for 120Y is abundance as the car was produced in taiwan under "yue loong" name till 1991.
TS,
for 120Y, get some weber and you're good to go.

do you even know what you're saying?

converting to 1.8L or 2.0L is ILLEGAL according to JPJ. not just engine need to be checked, the braking and suspension system need to be properly do up especially on such a light chassis. using runner? just wait till next round of JPJ checks, let see how many times you need to fork out money to check.

CA18DET? parts already out of production more than 5 years. no more parts. people are dumping this engine for SR20DET. there are other do-able engines such as SR16VE or nissan vanette A15 (plug and play).

4AGE 16V is cheap? the halfcut itself costs more than RM5k. engine is not old compared to 120y's stock engine and CA18DET. but sourcing for parts will kill you as people are jacking up AE86 part prices.

B13 rotary is good also, know one fella did it. power is good and car's body weight is balanced.

For RWD, you will not split your car in half. only FWD will.

parts for 120Y is abundance as the car was produced in taiwan under "yue loong" name till 1991.
TS,
for 120Y, get some weber and you're good to go.

which 120Y did you get? the B210 or B310? the b310 has 2 versions. one with round headlights then the later model came with the square headlights and the model just before the sunny 130Y had absorber bumpers. both have the same 1171cc engine. post a picture lah.

Why dont ask your grandfather since he is a mechanic ?

so why are u "dreaming" to get a wira? that's like saying u are "dreaming" to get Syphilis or AIDS or any kind of disease.

keep the datsun, keep the engine, uprade the brakes and chassis, get rid of the rusty parts, recond the interior and u'll have a sweet ride, much sweeter than the wira.

use the datsun until the ori engine becomes very problematic (which I think is highly unlikely, it probably will out live u if u take care of it).  Then u can decide whether to change car or change engine

can fit in SR16DE VVTL Neo engine....pure VTEC killer....but of coz, when moded, cant win 4AGE 20V engine d