3" mains

Was wondering if anyone out there is using 3" mains and what their experience has been?

 

Since no one else is taking a crack at it, I'll go out on a limb and show my true ignorance.

From my limited experience, 3" mains don't like a lot of RPM. At a given RPM, the crank surface to bearing surface speed increases significantly with diameter increases. Some feel oiling problems with high RPM 3" main engines are due to the need for additional oil due to the added surface area, increased surface area speeds and the centrifical forces placed on the oil inside the crank.

Fuel cars get away with 3" mains because they run slower RPMs.

Plus, I forgot to mention the increase in rotating weight. I'd stay away from it.

I could be wrong, but I doubt it.

 

Randy- a lot of fuel guys have also gone away from the 3in block. many reasons for this and I don't have a clue as to all of them, but odd ball combos, unless they show a significant advantage are not wise things to own!

 

I haven't been in the used block or crank market, but for a while the 3" main stuff was easy to find. Robert Rheel would know better than me.

When I first helped Dennis Taylor he had it and, at my suggestion, wisely updated.

 

we have in the past taken a 3" and had it ground down to std main some times you can get a steal on these as nobody wants them anymore