Rebuilding 4G63 Turbo with 4G63 NA

[Aikouka]

I know this question sounds somewhat odd, bu the only engine I could find that was even a 4G63 at a local Pull-It place was a NA 4G63.

I'll explain the predicament with the turbo 4G63 engine. Somehow a piston broke off from the 'shaft' (sorry for my crude terminology, but im referring to the shaft as the part that connects to the large cylindrical part of the piston and the other end of the shaft is the 'O' that connects to the crankshaft), and when it rose back up again, it smashed into a valve. The valve broke off and damaged cylinder #2. The head looks to be okay on the Turbo engine, but of course all of the valves will be replaced with the valves from the NA engine.

My father mentioned to me that the cylinder cannot be bored because the damage is too deep and oversized pistons are not made that large and that the cylinder cannot be sleeved, either. So I planned on using the block from the NA engine and simply replacing the Turbo engine's block. But everything else (with the exception of the valves) would be from the original turbo engine.

My main concern is if the NA engine's block will not work with the turbo engine (due to some hookup or bolt, etc. I have a guide (by Haynes) to repairing 1G DSM cars and it lists very few differences between turbo cars, and the biggest differences lie in the engine's electrical system where the NA has a 3 column x 2 row connector, but the Turbo has 4 columns.

Thank you very much for any help you can give me, this will save me a LOT of time and maybe some cash if I do not have to buy a block from a turbo. I hope to get this beautiful car going soon .

 

[91 NT Eclipse]

The only diff btw turbo and NA blocks are that the NA has 9:1 compression, turbo has 7.8:1, and the turbo block has oil squirters in the cylinders, NA doesn't. So you can use the NA block as long as its not a race engine.

 

[Aikouka]

Thanks for your help. And no, I wouldn't dare do any real power modifications (like the mods shown on dsmtuners) until I replaced the block with a turbo block.

Another quick question:

Are the pistons and crankshaft different on the NA model than the turbo? or will I need to take the pistons from the NA engine as well? In other words, are the blocks the same size (cylinder-wise) so the pistons will work, because I noticed that you said compression was different.

Thanks again.

 

[cuong1106]

The pistons have the same bore, I dont think there is a spot for a knock sensor, thats is a little cylinder that screws into the block in the back. You will need to drill and tap a spot for it. The engine won't have oil squirters unless you install thos....if you install those it will be fine to race. The non turbo rods and crank are both just as strong. How much is the engine?

 

[Aikouka]

The whole engine, without valve cover and timing belt cover (which includes the crank pulley and everything outside of the timing belt cover) was only $75 and is gauranteed for 30 days. Gotta love Pull-It places .

The knock sensor is required in the block, correct? Because I believe I was reading about if the knock sensor's signal is interrupted, the ECU does something. I cannot remember exactly what.

Could you also resleeve the original turbo head? I would think you just need to bore it out and then get a proper sleeve. But I can't find any sleeves for Mitsubishi engines. Because I was planning on using the NA engine block until I could find a turbo block or repair the old one.