Opinions on 60 over 4G63 Block

paper_clip_boy · 07-13-2006, 10:07 PM

I am asking this question because I am interested into the possibilties of this combo.

I know that if you use the 100mm crank and bore the block to 60 over that it would give you a 2.4L.

I know that Mitsubishi states that the Maximum overbore for a 4G63 block is 40 over.

I called Wiseco last week and asked them if they could custom a piston for me.
I told the that I wanted the Basic Stroker piston with 2 exceptions.

1. It needed to be for a 60 over block.
2. It needed to be 9:1 compression ratio.

They told me $459 USD for the pistons, rings, pins, and locks.

With these outlined conditions would this combo be able to sustain a 75-85lb/min turbo and with a proper valvetrain be able to rev to a MAXIMUM of 7500rpm.

GVR4592 · 07-14-2006, 02:09 AM

It's been done, there was a guy just a few months ago that bored his .080 over. There was also a link to site with some information on boring the 4g63 .060-.080 over. I looked around a little but I couldn't find it. It's in this sub-forum though.

paper_clip_boy · 07-14-2006, 01:48 PM

If anyone has any links or sites that they can post, it would be extremely helpful.

Im off to search the subject as much as I can.

Turbocharged · 07-14-2006, 03:55 PM

There is no problem going from 85.0mm to 86.5mm. The standard bore on a 4g64 and g4cs is 86.5mm. Im running 20 over to make it 87.0mm. The walls are thin between the cylinders but people have put down 600+ hp with this setup with no stuctural problems. The cylinder wall thickness is the same between the two blocks.

However you are only increasing the displacement 80.8cc's by boring it 60 over.