Hot Rods 3 5/16 tapered solid ring compressor

One of my flathead books mentions that a company named Motor Arts made a 3 5/16 solid tapered ring compressor - Motor Arts doesn't seem to be around any more - is somebody else making one of these in that size?

 

I don't know where to tell you to look but I had no problems building a flattie for my last project with a conventional ring compressor. Tim

 

Might try goodson.com they sell engine building tools.

 

Apologies for bumping a 10-year old thread, but I'm in the market for a solid tapered ring compressor for a 3.3125" bore too. ARP has an 84.0mm and an 84.5mm, but I haven't had any luck finding the 3 5/16" size. Anyone know of a source?

 

Total Seal makes an adjustable tapered ring compressor 3.300" to 3.400". To get a look at one Speedway and Summit have them. If it's what you want, shop around to price check.

 

For you guys with access to a lathe, they are a great thing to make. I made the first one a long time ago, when I didn't know how they should be done so it is way too tall (but works fine).

Odd bits of aluminum sometimes serve as material, but my favourite is old cast iron sewer pipe, available wherever old houses are being torn down.
Both the straight lengths and bells are handy.

 

Great idea! Now if only I knew how to cut an accurate taper on my lathe.

 

For as short of a taper as you're going to need. For a ring compressor, just use the compound.

 

Thanks, guys. I've thought about asking my dad to make me one on his lathe, I might go that route. Gives him another project to do in his retirement, which will make my mom happy, ha!

 

Can I ask why a normal spring compresser won’t work?

 

That's what I do, and I adjust it so that the big end of the bore is a smidge bigger than the diameter of a relaxed, uninstalled piston ring.
Regular compressors work, but sometimes are tricky for getting the three piece oil control rings in.
Plus, it's really satisfying using the specific solid taper compressors.

The biggest issue with making these things is to not distort the piece in the lathe chuck by over tightening, but not have it too loose so that it comes out while turning.

 

My understanding is that "normal" adjustable-style versions work, but not as well as a solid tapered one.

 

Normal ring compressors work fine, however if you have ever used a taper one they are so much nicer.

 

I built a lot of 3.313 bore flatheads. A R P 84 MM is what I use. Had to sand the small end a little bit.