Turning the crank

[laserspeeddemon]

Short and sweet:

Someone from another DSM forum said that you can't turn a 6-bolt crank. Is this true? I've never heard this in 12 years of being a DSMer, but that doesn't mean I can't learn something new.

If I can't turn the crank what are my other options for my rebuild.

 

[95blackGsTurbo]

You can turn a crank no problem. I have built a couple motors with .010" undercut cranks. It takes away from the coating but for all sub-1000hp builds there won't be a problem. Usually a good polishing will take care of any imperfections though.

 

[laserspeeddemon]

Well may as well dive into it.

I looking for a mild build, 400 hp tops, but I will stay around the 300-350hp range. My plans for this build:

Pistons: EVO IX maybe coated tops to help keep heat in the cylinders
Rods: 1g Big Rods
Other Engine: BS delete. New Oil pump cover, new water pump, new gaskets (obviously)

This will be my first lower-end build. I assume I don't really need to file the piston rings. I was going to bore the cylinders 0.020 over and get 0.020 pistons with 0.020 rings. When installing the main and rod bearings, does anything need to be machined. What if any clearances need to be checked. How hard is installing a balance shaft delete kit. Do I need a press?

What I am really looking is just to build an engine, with all the work done myself minus machining that reliable. I am not looking to make MASSIVE amount of power. Where I really need to spend money on is the transmission, chassis and suspension as this will be a Rally Car.

 

[DeNoZZo]

Well may as well dive into it.

I looking for a mild build, 400 hp tops, but I will stay around the 300-350hp range. My plans for this build:

Pistons: EVO IX maybe coated tops to help keep heat in the cylinders
Rods: 1g Big Rods
Other Engine: BS delete. New Oil pump cover, new water pump, new gaskets (obviously)

This will be my first lower-end build. I assume I don't really need to file the piston rings. I was going to bore the cylinders 0.020 over and get 0.020 pistons with 0.020 rings. When installing the main and rod bearings, does anything need to be machined. What if any clearances need to be checked. How hard is installing a balance shaft delete kit. Do I need a press?

What I am really looking is just to build an engine, with all the work done myself minus machining that reliable. I am not looking to make MASSIVE amount of power. Where I really need to spend money on is the transmission, chassis and suspension as this will be a Rally Car.

Just some things I learned from my engine build. Take them as you want.

-Any piston rings other than the oem ones may need to be filed to the correct gap size.

-If you are going to use arp studs for your rod bolts or main bolts. Get the big end of your rods and your main journals align honed after you install the arp's.

-ALL CLEARANCES SHOULD BE CHECKED. Don't make the same mistakes I did.

-The balance shaft delete kit is fairly simple. You can use either a socket and mallet to knock the old ones out and tap the new ones in, or I think you can turn the old balance shaft around and use the big end on that. This will take some muscle, time, and patients.

Good luck!

 

[JacksonAuto]

Well may as well dive into it.

I looking for a mild build, 400 hp tops, but I will stay around the 300-350hp range. My plans for this build:

Pistons: EVO IX maybe coated tops to help keep heat in the cylinders
Rods: 1g Big Rods
Other Engine: BS delete. New Oil pump cover, new water pump, new gaskets (obviously)

This will be my first lower-end build. I assume I don't really need to file the piston rings. I was going to bore the cylinders 0.020 over and get 0.020 pistons with 0.020 rings. When installing the main and rod bearings, does anything need to be machined. What if any clearances need to be checked. How hard is installing a balance shaft delete kit. Do I need a press?

What I am really looking is just to build an engine, with all the work done myself minus machining that reliable. I am not looking to make MASSIVE amount of power. Where I really need to spend money on is the transmission, chassis and suspension as this will be a Rally Car.

Some OEM piston rings do not need to be filed but you ALWAYS want to check the gap before installation.

In addition to boring the block, you will also want to be sure it's plate honed and also square decked. Square decking will eliminate any imperfections in the deck's surface and will also be sure that the cylinders are located perfectly perpendicular to the crank and that the pistons will be parallel with the deck.

Clearances that need to be checked are as follows-
Main bearing oil clearance
Rod big end ID
Align bore
Rod bearing oil clearance
Thrust
Rod side clearance
Pin bore clearance in the rod and piston
Piston ring end gaps
Deck heights

You do not need a hydraulic press for the balance shaft bearings but there is a special too for installing them. The machine shop that does your work for you should be able to put them in.

We are not far from you. PM me if you'd like a price on machining your block. Watch out for shops that don't do 4G63's every day because they wont have the necessary equipment and experience.

 

[turboglenn]

My machinist and a few others i've talked to said they won't turn a mitsu crank, something about the way the plugs are installed after the oil gallies were drilled not allowing the metal shavings to be cleaned out of the crank afterwards and then them getting into your engine's oil system and eating things up... becuase of this i now have 3 perfect 6 bolt OEM cranks sitting from my last build because my mnachinist refused to let me take it untill he got the clearnances HE wanted to see .. Now i have 2 more to sell along with a 2g turbo FWD tranny i built for a guy with a 1g diff so he could put it in a 1g but never paid me

 

[donniekak]

My machinist and a few others i've talked to said they won't turn a mitsu crank, something about the way the plugs are installed after the oil gallies were drilled not allowing the metal shavings to be cleaned out of the crank afterwards and then them getting into your engine's oil system and eating things up... becuase of this i now have 3 perfect 6 bolt OEM cranks sitting from my last build because my mnachinist refused to let me take it untill he got the clearnances HE wanted to see .. Now i have 2 more to sell along with a 2g turbo FWD tranny i built for a guy with a 1g diff so he could put it in a 1g but never paid me

Tell your machinist to pull the balls out of the oil galleys, and tap the plugs for set screws.

 

[turboglenn]

that was my first reaction, but no one we called or spoke to about the DSM crank could tel us how to get them out, i guess they aren't the same as chevys and such

 

[Codester]

My old machine shop was the same way turboglenn. They didn't know how to take the balls out of the crank. So I shipped it to a vender on here.

But you know Mitsubishi likes to do things that nobody else does and pisses people like us off. In turn.... Nobody knows how to properly work on our cars unless they are really experienced. Haha

 

[BIGBLAZE79]

Had my crank main journals turned 10 thousanths and rod journals 20 thousanths. Had the crank renitride coated then back to the machine shop to be micropolished. Mine has worked just fine. I think nitride coating was about $75. You would have to have a heat treating facility in your town or ship it I somewhere I guess.

 

[dsm-onster]

Nitriding is overrated. I've killed more stock cranks than cut cranks. The nitriding is to prevent damaging wear to the crank. But I don't know about you, I can't tell to cut a motor off BEFORE the bearing contacts the crank. It's only the noise that tells us to cut it off. If you hear the noise, it's too late: the crank has already been damaged, nitriding and all.

So along with the above, guys like Kevin Jewer, and coltboostin (700+ whp cars) run cut cranks. What's there to lose?

Perhaps nitriding is there for the warranty fiends who don't change their oil until in has the consistancy of oatmeal and there's not been an "engine noise" yet. No one here should even be discussing the merrits of a mechism/characteristic that is in place for such a happenchance.