g62b (1.8L, sohc, 8v, carb) question

[ochi]

good day everyone! i'm ochi from the philippines. i joined the forums because i want to learn a lot of engine modding from you guys. hopefully i can share my builds when time allows me to.

by the way, i recently acquired a g62b engine (1.8L, sohc, 8v, carb) that came from a friend's 2nd gen mitsubishi lancer 1800 gsr... he sold the complete engine to me for only US$100...

i know it's the smaller brother of the g63b engine (2.0L, sohc, 8v, carb) that came from the mitsubishi L300 vans so its stock stroke is 90mm and the only difference between the two engines is their stock bore... i was wondering if i can use the 4g64, g64b, or g4cs internals (crank, rods, pistons, etc.) to bore and stroke this 1.8L engine to something like 2.3L or even 2.4L... i'm planning to put my solex/mikuni/kogyo twin side carbs into the engine during the buildup...

hoping to hear some enlightening answers from the experts and gurus here... thanks and more toque and horsepower to everyone's rides!

 

[spoonman]

That engine is part of the Sirius family of Mitsubishi engines. The stoke is 88mm and the bore is 80.6mm. The block is a narrow 6 bolt engine which means that it has the same block as the 4g63's in Eclipses'. If you want to keep it carbureted you should probably stay with a factory carb. Mitsubishi head, but if you wanted to turbocharge the engine or make it Electronic Fuel Injected (EFI) you could swap to a better designed head from the 4g63. For 4g63 engines to make a 2.3 stroker it requires a 100mm crankshaft, 150mm rods, and "stroker" pistons which have re-engineered wrist pin heights to accommodate the extra stroke. If you wanted to make the g26b engine into a "stroker" you would have to find a 100mm 6 bolt crankshaft, as far as choice in rods I am not sure what the rod length is for that engine standard but 4g63 have 150mm rods, and then the "stroker" pistons, you could use the 4g63 pistons but the engine would have to be bored to 85mm's.

 

[ochi]

thanks for the reply! about the bore and the pistons... can i bore it out to 88mm and use 88mm stroker pistons just like what most people do with their 4g63s and 4g64s? and by the way, would anyone know who sells these 88mm stroker pistons the cheapest? i'd really like to order a set as soon as possible so that i could test the setup on track on our club's track day at jan 2010... and another question, where can i source 88mm head gaskets for the setup? and one last thing, nobody from our club supported my idea on stroking the engine... they said i'd be happier if i square the engine specs... but i know what i want and that is more torque at the lower rpms (which i believe the stroker would give me)... besides, i'd be using the setup for street and circuit, not on the drag strip... looking forward to everybody's opinion... thanks!