MONZTER Posted August 20, 2007 Share Posted August 20, 2007 So, on a L-28 turbo build with 1973 240 rods, should I close off the oil squirter hole in the rod or leave it open??? Does anybody know what the pros and cons are?? Thanks Jeff Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted August 20, 2007 Administrators Share Posted August 20, 2007 It is for cooling the piston. My thoughts are for a moderately to highly boosted L-series, that the oil squirter should be retained as the pistons need all the help they can get in keeping cool. Quote Link to comment Share on other sites More sharing options...
MONZTER Posted August 20, 2007 Author Share Posted August 20, 2007 Hey Braap, Makes sense about the cooling, so why would anybody want to close them off at any level? I know they talk about it in the "how to modify book" Is it because of the extra windage? or maybe the high RPM loss of oil in the rod bearings? Hmmm Thanks Jeff Quote Link to comment Share on other sites More sharing options...
Tony D Posted August 20, 2007 Share Posted August 20, 2007 I asked the question one time about the orifice size on the Z32TT engine, as well as the original VG30's with turbos...they had dedicated oil squirters for the piston crowns, and I wanted to investigate this for the L on a...er..."High Specific Output" Turbocharged L-Engine that would be operated at boost for long periods. Like 5 minutes to 10 minutes at WOT at a stretch. I figure at that kind of loading, all the cooling I could get to the piston crowns to remove heat will be helpful. Some of the stuff those rod squirter holes do is lubricate the piston pin as well...the rod isn't gun-drilled for forced lube up there, so the squirter and piston crown drainback is all that lubes a full-floater! Quote Link to comment Share on other sites More sharing options...
jc052685 Posted December 25, 2009 Share Posted December 25, 2009 Yup, bringing back a seriously old thread but, does anyone else have any input on this? Quote Link to comment Share on other sites More sharing options...
1 fast z Posted December 25, 2009 Share Posted December 25, 2009 Squirter always goes to the pressure side of the piston. The pressure side of the piston, is the right side of the engine, if sitting in the drivers seat. This only applies to motors that turn counter-clockwise if sitting in the drivers seat. Quote Link to comment Share on other sites More sharing options...
jc052685 Posted December 25, 2009 Share Posted December 25, 2009 There is some good info! Quote Link to comment Share on other sites More sharing options...
josh817 Posted December 25, 2009 Share Posted December 25, 2009 Hey Braap, Makes sense about the cooling, so why would anybody want to close them off at any level? I know they talk about it in the "how to modify book" Is it because of the extra windage? or maybe the high RPM loss of oil in the rod bearings? Hmmm Thanks Jeff In that book and another one I have it says they take them off because "the piston receives a substantial amount of oil without the squirters", whatever thats suppose to mean since we can clearly see every application is different. Now, I don't think they meant plug the hole when they said that though. What I mean by take them off is grind off that hump. I did that on my rods and the hole still kind of points upward but without the hump. So I guess it may be spraying to the bottom of the pistons, or it may just splatter, but I wouldn't plug them because: -like Tony said, full floating wrist pins, keep'em lubed -helps cooling to a certain extent and with crazy motors every little bit helps (you know that already) -and like 1 Fast Z said, only sprays on the right side so I doubt it would "equally lube" Heres my finished product, you can see it still kind of points towards the piston: And here is a stock U20 rod for a comparison: I also want to note, since I know all of us here are very particular about our motors, except myself really... But shouldn't we look into whether oil is spraying all the time through there or does it spray in pulses? Point being, after seeing that U20 rod again, that hole has to line up with the galley in the journal of the crank for it to spray, right, like a pulse? And our cranks are cross drilled... right? That means it would squirt twice every 360º. So, are those oil galley holes at the very top and very bottom of the journal? If not, that means the rod is at an angle, therefore the oil squirt would not hit the bottom of the piston, but rather like... somewhere else because the squirt hole faces upwards (or close enough). If the squirter isn't even pointing towards the piston when its spraying, all this effort may be stupendously useless! Quote Link to comment Share on other sites More sharing options...
jc052685 Posted December 25, 2009 Share Posted December 25, 2009 Now are these "squirters" only on the L24 rod and not on the L28 rod? What kind of temp reduction would the piston see with these vs with out? Quote Link to comment Share on other sites More sharing options...
josh817 Posted December 25, 2009 Share Posted December 25, 2009 Now are these "squirters" only on the L24 rod and not on the L28 rod? What kind of temp reduction would the piston see with these vs with out? Let me check to see if I have any L28 pictures when I tore mine down... This is the only one I found of L28 rods I had: You're looking for this: So no it appears they don't have it... If someone were to switch to some nice forged whatever-beam rods I wonder if they would even have the hole at all... Quote Link to comment Share on other sites More sharing options...
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