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I remember when

I first brought up using an FE head on an F2 block and people thought I was nuts for saying it could be done.
 

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I first brought up using an FE head on an F2 block and people thought I was nuts for saying it could be done.
You haven't been around since the turn of the millennium, so no you didn't. No offense.

As for oiling differences on the F- engines, has anyone noticed that F2 rods do not have a notch machined into the big end that points upward, but FE-DOHC, F8-DOHC etc do? The little notch is parallel to the rod's beam, which indicates that bearing leakage is directed up towards the piston
 

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f2 rods have a little hole drilled in them to point oil up to the piston.

Although I have not pursued the stroker since mine spun a bearing, my machine shop used to deal with a bunch of stroker porsches running into the same problem, and their solution was to notch the oil hole in the rod journal. What made him think of it, is if you lay the fe3 crank flat on the counterweights, all the oil holes point the same way, but the f2 does not. The extra stroke must need full oil pressure in the rod journal at a specific time, and so the f2 crank has all the holes clocked so the main oil feed lines up with the holes in the main journals, feeding full pressure through the crank to the rod journals. When we stroke the motor, it moves where the hole is in the rod journal compared to the rod angle. Notching the oil hole on the rod journal extends the period of time the high pressure will hit the journal.

All the mazda cranks I've dealt with, and admittedly I have not dealt with nearly all of them, have all the holes drilled out, then the cross holes that connect the rod journals to the main journals passes through the rod journal and has a plug just outside the journal in the unmachined part, meaning they drill through from the outside and just plugged the hole, easy and cheap. The f2 is all at strange angles and doesn't have these plugs, so mazda must have felt it important, as they had to take more time drilling these holes.

I can take pics if anyone wants, I understand the reading may not make sense.

@bpt...we didn't all realize there were gonna be oiling problems when we did it, at the time, it made sense to me to swap pistons and have the 2.2L. I drove the car for nearly a year before I noticed the slight ticking that slowly got worse, until I finally pulled the pan. I didn't know I was shortcutting anything, and wasn't too worried about the rod angles as I didn't plan to spin it too high since the intention was boost.
After driving it for that amount of time, I had decided I would be happier with the shorter stroke, and sold off the stroker pistons. Although I don't talk to him much, I know the buyer of them had started running them a while back and I haven't heard of him having any issues with it, I think he did some crank work for it, I can try to find his build, he posted a little about it here when he was doing it.
 

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Hey I just wanted to update this issue, after a bit of research.

f2 rods have a little hole drilled in them to point oil up to the piston.
This is the it, this is the missing link.

There are two main types of bearing lube configurations in the industry; the F2 'hole in the rod' type and the FE3 'drilled straight thru oil journal, side
leakage' type.

The FE3 type is shared among other Mazda engines, including the K-SERIES V6 and B-SERIES. It involves a simple, single-plane oil port, drilled straight through rod journal. These oil holes are not aligned in any particular way, just that there are two of them. Machining them is much easier. Most of the time, this style of bearing is combined with actual oil sprayers under the pistons. What happens is oil slowly permeates through the bearing out of the two oil holes, heats up and leaks out of the side of the bearing. On the connecting rod, there is a small notch on either side of the big end, at the top of the big end, just below the rod beam. All leaked oil eventually exits through those notches on the side.

The F2 type rod includes no notches on the side of the big ends, a small oiling hole drilled into the rod pointing up at the piston, and a single, specially angled oil hole designed to line up with the F2-rod oil spray hole when it's aimed at the piston pin. Since the F2 has no oil sprayers, this once-per-revolution squirt of oil is the primary means of lubricating the piston pin, and also inducing momentum into the oil flow.

NOTE: Many other engines use the F2 style rod with a small oiling hole such as the Honda h23 and the Toyota 7M-G(T)E for instance, since I have both parts handy.

When an F2 crank is used with FE3 style rods, instantly the oil supply to the bearing is halved. Furthermore, since there is no open hole to induce a 'pulse' in bearing flow, oil supply is again reduced further after already being halved. What happens in terms of bearing failure is that the oil in the bearing journal overheats because it remains in the bearing for too long, because of a severely reduced flow. This is an 'accelerated wear' condition, not a catastrophic failure mode and would take some time to manifest itself. I also suspect that the special angle of the rod journal oil port on the F2 crank is sub-optimal (aside from there being only one instead of two).

So this is a problem that can happen across engines from all manufacturers, since most engine manufacturers have chosen one or the other style.

The solution would most likely be to drill the F2 crank hole straight through, OR drill the identical oiling hole into the FE3 rod and use F2 bearings- if one was going to do the mix and match route.

Ultimately which oiling style is better? IDK. I'd be prone to favour the FE3 style, but people have reved their F2s over 7k on stock bottom end without a problem- so I'd say settle for whichever is easier.
 

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There are still 2 oil holes in the f2 rod journal, but they're just not at 180 degrees from each other, they seem to be timed with something, such as rod angle, or whatever. It might be the oil hole in the rod, but, like you said, the fe3 rod has the notches in the sides, so they should still be able to move oil, just not necessarily direct it to the pistons, since the block has squirters.

Maybe it's worth getting pictures of this all just because the nature of the thread, I'll go take some today and get them uploaded over the next couple maybe.

I know the KL cranks have multiple oil passages drilled into each main journal, I'm sure just to make sure enough pressure pulses are there to feed 6 rod journals from only 3 mains, as the thrust main I don't believe supplies oil to nay rod journal, I'll double check.

I think the FE3 crank shares the oil passages with multiple other mazda motors is simply the fact that none of them have a stroke close to the f2, considering the f2 stroke is quite long, comparable to big block v8s...f2 is 3.70" and a 460 ford is 3.85, 390/427 ford is 3.78, and chev 396/400/427 is 3.76. It's good to know some people are still curious about it though, interest in these cars seems to have died over the last couple years:(

I still have my fe3 and want to build it, it's just been slow going lately on all my car stuff. I have 2 2gens I wanna put together, then I'll hopefully start putting my 2 1gen pgt's back together...
 
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