Cool.

 

We have forged rods too. It's just our pistons that suck.

 

The pistons are the same as 3S/VR4 pistons, except for a special coating and different ring gap. At least that's what I've heard.

 

Well damn so what im reading from this thread is by installing some nice CP forged pistons in my 6G72 and my bottom end will be forged. :dunno:

 

Just make sure to get your ring gap correct. I didn't gap my rings and now I have an engine that is quickly turning into a very heavy paperweight.

 

The pistons are the same as 3S/VR4 pistons, except for a special coating and different ring gap. At least that's what I've heard.

That is incorrect. The piston design IS different. The VR4 uses a lower compression 8.0:1 compression piston while the 3G uses a 8.9:1 compression piston w/ a smaller ring land.

 

oh snaps any idea of how much boost/punishment they can take before you would need to upgrade?

 

oh snaps any idea of how much boost/punishment they can take before you would need to upgrade?

More boost than you could afford! :lol:

 

well i guess that answer my question in a sort of pride reducing, sarcastic tone.... thanks greg...:squint:

 

I'm pretty sure some 3S guys are running upwards of 900 AWHP on our forged cranks (we share the same crank I believe). Don't quote me on that number, though.

 

Soda can pistons FTL. :fawk:

 

it pretty exciting seeing this motor come together after being out of my car. man i cant wait, a few months from now and you are going to eclipse expectations rather quickly. make sure to take pics throughout the process tim. oh and ill be around when you need help with anything so let me know. are you going to have anything done to the heads?

 

so we have forged cranks and rods. why is people changing there cranks to the forged vr4 cranks and the crower rods when they do there internals.shouldnt are internals be sufficent for boost except are pistons.

 

Yes, our crankshafts and rods are good for an ungodly amount of boost.

Personally, I'm replacing my rods because the old ones in this block were bent because of hydrolock (thanks boostzealot :fawk.

Larger ring gap on 1st and 2nd rings is a must. Forged pistons and a regap is what is really necessary for a healthy amount of boost.

 

Can the same be said about the 6G74? forged rods and crank?

 

Tearstone posted this image of a 6G74 he had the oil pan off of:

. The crank looks forged to me.

I'm guessing the rods are forged too.

 

Post a pic of it. It sounds like the thrust bearing on the center of the crankshaft.

 

All forged cranks are not created equal. The quality of the steel before forging makes a big difference. However, the bottom end of the 6g72 has shown to be pretty strong.

 

Here are different angles of the pieces. They aren't made of metal if that helps.

 

Is it plastic? Chunks of your timing belt cover? Dunno

 

most cranks now days are forged, forged out of what material is the question

 

Well I don't think any 3SI guys have broken this crank yet, so I'm sure it's adequate.

 

ya it's thick plastic. It's definately not the timing belt cover. The plastics were found at the bottom of the oil pan.

 

the 3g 4g64 and 6g72 motors and pretty much all mitsubishi motors use an iron Block with aluminum head, forged cranks and fracture-split forged powder metal connecting rods =o) juss some info for u guys.

 

The previous generation 6G72 (1st gen 3000 GT/Stealth) did not have a forged crank and it was boosted.

 

Also the V6 GTS 2002+ has a 10.0:1 compression on its pistons, and the v6 was sold in japan as a left hand drive car.

 

ahh ok lol well then umm almost every mitsubishi has a forged crank lol yea i know the older 6g72 was tt i used to own a flippy light 91 vr4 awd all wheel steering with different modes of driving for different exhaust tones and the motorized tilting adjuatable rear wing =o)

 

Well, a little off topic, but I just dropped off the short block at the machine shop. Bad news is that they can't balance the crank (no V6 bobweights). I've got to find another shop to do that.

Would you guys be interested in a thread covering the engine build? I think I'm going to create one over on TGC - I'll link to it here if I do.

 

I wouldn't mind one. I could probably use it as a reference guide for my build

 

yes, forged cranks have been broken, and many have been cracked over time when pushed above 800.

 

This thread is almost a year old noob.