Considering engine options: 4G64 turbo...

Here is a bit of a spill and the research results on the 4G64 engine option for my Sigma. This engine and the rwd gearbox to fit would be quite easy to find as it came out in many Mitsubishi vans, Tritons and now even in the Chinese-made Great Wall V240.

Here are the engine's technical details (stock):

Type: 2.4L 4 Cylinder
Capacity: 2378cc
Bore x Stroke: 86.5x100
Compression Ratio: 9.5:1 (Express and Triton), 9.8:1 (GW V240)

Power: 97kw (Express and Triton), 100kw (GW V240), 103kw (Nimbus), 105kw ('98 2.4 Magna)

Torque: 192Nm (Express and Triton), 200Nm (GW V240 and Nimbus), 205 Nm ('98 2.4 Magna)

The good points of this engine option are: 16 valves and even variable valve timing in some cases (4G69 MIVEC), 2.4 litres of capacity, which could be enlarged to 2.6 to match the size of the Astron engine (just for fun) and I think there's a possibility the 4G63's twin cam head would also fit. To turbo the engine would just be a matter of strengthening the engine up with forged pistons etc.

Fitting the engine and gearbox should be no problem either as long as a rwd 4G64 and gearbox from Express, Triton or even GW V240 is used. A larger Triton radiator would be good too.

Above is a photo of the GW V240 engine bay. You can find more info on the GW V240 here: http://www.greatwallmotors.com.au/default.asp?action=article&ID=21562 and here is a photo of the V240's 2WD gearbox:Info on fitting a 4G63 twin cam head to a 4G64 block can be found here: http://www.extremeevolutions.com/4G64_buildup.htm

Info on fitting a 4G63 or 4G64 engine to a rwd car can be found here: http://www.projectzerog.com/archives/ZeroGversion2/transmissions.shtml