dd-ardvark
January 8th 2003, 18:00
I have a pair of New Old Stock 914 2L heads that were cut to 112mm spigot hole and the chambers were never opened up, so the head registry is still there. This is the surface that a stock 94mm, and After-mkt. 96mm barrel would rest against in the head. The heads will be opened up to 115mm that of a 103mm steel, same as 100-102mm http://www.lnengineering.com/nickies.html cylinders outside dia.
I want to use these heads with NOS 98mm Mahle/Okrasa/Oettinger aluminum cylinders, that have an outside barrel dia. 106mm. Yeah, 4mm, REAL thinnnn cylinder walls, but a good machine shop can make spacers for the outside of these cylinders without to much of a problem. They will be 4.5mm+/- thick.
A little background: I've done this on type1 motors using steel on cast steel cylinders, and it was an interference fit to the cylinder. Case in point, 88mm slip-in cylinders, this is a thin walled barrel (stock 1600 outside dia.) and the head spigot hole was 101.5mm, cut for 90.5-92mm barrels...To answer your question this was done just as an exercise in bastardization at it's finest. No, we didn't plan on the motor living for any great length of time, it was an old tired engine to start with, and the motor only lived for about 6 weeks, and died after it swallowed a small Gremlin. We knew it had, because HE kept knocking on the case real loud... Anywho, when the heads where pulled, no leaks at the cylinder and head were evident, discounting the one that the piston was slapping against.
Question: Should I make the spacers an interference fit to the cylinders (pressed on), or to the heads (pressed in).
Question: Should I even be concerned with an interference fit.
Also: My thinking is to make the spacers of aluminum this time instead of steel, to coincide with the aluminum cylinders. Keeping in mind both the head and cylinder are cast aluminum.
Question: If you agree to the aluminum spacer, what type/grade of aluminum should be used.
Either way I will be using LN-Engr's. Head Stud and Hardware Kit because of their research into the thermoexpansion differences between aluminum and steel.
Calling all bastardization experts and or real ones, your thoughts please. dd-ardvark
I want to use these heads with NOS 98mm Mahle/Okrasa/Oettinger aluminum cylinders, that have an outside barrel dia. 106mm. Yeah, 4mm, REAL thinnnn cylinder walls, but a good machine shop can make spacers for the outside of these cylinders without to much of a problem. They will be 4.5mm+/- thick.
A little background: I've done this on type1 motors using steel on cast steel cylinders, and it was an interference fit to the cylinder. Case in point, 88mm slip-in cylinders, this is a thin walled barrel (stock 1600 outside dia.) and the head spigot hole was 101.5mm, cut for 90.5-92mm barrels...To answer your question this was done just as an exercise in bastardization at it's finest. No, we didn't plan on the motor living for any great length of time, it was an old tired engine to start with, and the motor only lived for about 6 weeks, and died after it swallowed a small Gremlin. We knew it had, because HE kept knocking on the case real loud... Anywho, when the heads where pulled, no leaks at the cylinder and head were evident, discounting the one that the piston was slapping against.
Question: Should I make the spacers an interference fit to the cylinders (pressed on), or to the heads (pressed in).
Question: Should I even be concerned with an interference fit.
Also: My thinking is to make the spacers of aluminum this time instead of steel, to coincide with the aluminum cylinders. Keeping in mind both the head and cylinder are cast aluminum.
Question: If you agree to the aluminum spacer, what type/grade of aluminum should be used.
Either way I will be using LN-Engr's. Head Stud and Hardware Kit because of their research into the thermoexpansion differences between aluminum and steel.
Calling all bastardization experts and or real ones, your thoughts please. dd-ardvark