Vitos +3 crank stuffer blocks

[Blaner]

PLUS 3 MM STROKER CRANK...

what exactly are these stuffer block made of? are they the blue part on the crank? how much do they displace and is it just enough to get it back to standard volume or does it decrease it further?

 

[slickerthanyou]

It decreases the volume I would think even more than standard as it is 3mm larger and fully stuffed.. I have that exact crank. Yes the blue stuff is the stuffer. I don't know what it is made of but when I blew the piston , it just scratched it. , seems like some kind of urethane?? But very hard not soft at all.

 

[sicivicdude]

It's not soft.

Mine is hard plastic. Rockwell hardness similar to delrin or PVC.

I believe the stuffer block reduce the crankcase volume below factory volume. It's hard to test that theory because even the standard vito's crank now comes with the stuff blocks... You can't even take the regular crank throws from the vito's crank and test displacement that way.

 

[Braaaptor]

They're made of Delrin, I think. Some kind of extremely-hard, durable plastic composite. Honestly, I'm not scared of plastic moving around inside the engine; like Slicker said, its very tough.

They have been putting plastic camshafts (I BS you not!) in small Briggs and Stratton and Tecumseh engines since the early 1990's. They keep right on running, with most of the valvetrain problems I see coming from burned exhaust valves. Matter of fact, I've seen more of the traditional ground metal cams go flat than those with plastic lobes. Plastic has come a long way...