hi, i have 2 4g63 blocks for my evo 3...i noted yesterday after pullin both apart that the oil squirters differ....one has a seperate fitting that can be pulled of the block and replaced and one seems inbuilt....since this is a part that can potentialy fail,,which of the 2 would be better to use

 

 

sorry bout the bad quality pics....the first one is the removable jet,,,,,the second one seems to be just below the main bearings, or in the middle of the journal

 

nothin?

 

I'll help you out a tad. If it was me i'd use the jet style. The ones that look like little nipples pressed into the block like to clog up and stick open sometimes. There is a big controversy this may also be the reason for the notorious crankwalk. I believe Magnus did a write up on the problem with that style of squirters. They aren't supposed to open and release oil at idle/low rpm's where there is low oil pressure so as not to starve the main/thrust bearing of oil.

Well the theory is they have a shady valve that sometimes gets stuck open and starves the bearings of oil. Also the jet type is what's in evo8&9 blocks as well as most 6 bolts. PM me for any more q's.

Also if you plan on doing a forged internal build which seems likely the case as you're starting with a bare block, you don't need to run squirters. This gains you extra oil pressure and leaves one less thing to fail. With the jet squirter block they can easily be blocked off with a stubby bolt . Just make sure it only goes down a few threads. If you go down too far you'll starve the main bearings when you block off the main oil galley.

If you're running stock/cast internals you should keep the squirters or else you may have some melted parts. You would've had better luck with this question on dsmtalk .

 

thanks for the help....so as i understand it the block in the first picture is the one to avoid..

 

No no you want to use the ones that bolt in and have a tube going to the bottom of the cylinder.


In other words the one in your first pic not 2nd or 3rd.

 

oops...ive already built the engine using the other block..ie the 3rd one...i thought it was a newer design, doesn't the one in the first pic tend to stick open if they get contaminated and then cause a loss of oil pressure?

 

ok so since i made the mistake of useing the wrong block for the buildup what can i do to prevent the jets from getting clogged? is it as easy as frequent oil changes,or flushing the engine after a oil change? what about the type of oil? im thinking mobil 5-50