Crank bearings failed?

 

yes it did.

 

http://www.dsmtuners.com/threads/man...f-rods.499390/

 

That doesn't make sense. It doesn't seem like the cause is the rod and piston combo. And oil seems odd too since their purpose is to lubricate.

 

Main bearing failure is more rare than rod bearing failure, but it can happen under a few circumstances.

1. The main bearing oil clearance was not set properly
2. The Crank was bent
3. Loss of oil pressure/oil film strength
4. Bearing crush pressure was lost due to improper torque spec on main studs, causing the cradle to back off (highly unlikely with single piece, cast iron cradles)

On the rod bearing side the list is similar, but it's much easier to spin a rod bearing because all what's needed is to stretch a rod bolt.


I'm sure that I beams will cause the rod bolts to stretch faster than lighter weight rods, but if you keep your engine low reving (7500 - 8000rpm) it won't be too much of an issue.

 

Im not sure of what the exact caused as i left it to my mech to work on it. was told its the oil.

Thanks for the info the engine was 3 to 4 years old after rebuilt. The crank wasnt bent but definitely there was loss of oil press.

Let me share what had happened.
i had 2.0 built engine and was using amsoil and motul 300v. the car was running t3 gt37 pushing 700hp for few years and had no issue. changed to fp black and used motul xcess got it tuned 2 days later before the bearings give way.
i had few frenly drag with some frens, 1st run was fine, after 2nd run the oil temp shoot pass 110, water temp was only 86 and oil pressure drop below 1.3bar. let it cool down and check oil and radiator. topped up few ml of oil. Start again, at idle, it shot passed 110 within 1min. decided to call it a day while on the way back, the engine was vibrating badly, oil press fluctuated and oil temp hovers at 115 so i suspected either oil pump gave way or oil gotten thin.. stopped somewhere after bearings gave way and got it towed to my mechanic. During the runs, i was on low boost - 1.5bar and shift gears at only 7.5krpm.

So i decided on 2.2kit. Gotten htuff which is thicker than normal h beams but there wasnt much info on this rod. Wish to know before tune and how far i can push it.

 

What was the specs of your old engine (if you don't mind giving out that info)?

 

How is your new 2.2 kit compared to 2.0? Is it bored bigger or stroked?

 

2.2 is 94 mm crank...

 

And I assume pistons are about 86.25 mm to get 2.196 L or 86.5 mm to get 2.2096 L?

Crank/rod radius increases by 3.4%. And goal rev linit is still 9000 RPM?

I think proportion to 1.997 L, 9000 RPM should be reduced to 8426 RPM. Otherwise, it's like pushing your 2.0 L 9000 RPM to 9614 RPM.

 

Max bore size on 4g63 is 86mm. .020" over (85.5mm) with 94mm crank is ~2.16L.

 

yeap 94mm crank. i might start a new thread for my build. now lets come back to the topic..

 

ups

 

For the record the htuff 156mm do not clear the block with the 100mm crank. Clearancing like with ibeam's is required.

 

correct.