are these Offenhauser main caps ?

came across these in my shop the other day. someone told me they are Offenhauser main caps. they are solid brass. the two smaller ones are identical with the numbers #653-3 #270 on them. the larger one has number #70 cast on it. anyone know what they fit ?


http://i276.photobucket.com/albums/kk4/jbarzda/auto parts/Picture042.jpg

 

Look like offy mains...and there was a 270 offy. There's a 270 offy tech article with many pictures in an old HRM about 1956...I was just looking at it, so it must be near top of one of my heaps.
I was expecting to see the little reinforcement straps for flatheads that used to be in the Offenhauser manifold catalog whae I opened this!

 

They most certainly are the Miller/Offy diaphram type main bulkheads. You gotta heat up the whole crankcase to put the bulkheads and crank in.

 

So HOW does someone just have spare Offy parts laying about!?

 

I'm guessing that that is the total of what you get to keep when a rod lets go in an Offy...anybody with a scanner have the HRM article? It's practically and Offenhauser assembly guide.

 

if you could narrow the issue of hot rod i would appreciate it. i should have the issue

 

i have lots of old parts laying around

 

I'm at work and so have no way to narrow...can probably find it tonight.

 

thanks, i will post a scan for everyone if you find what issue it is

 

HRM June '58, starts on page 35.

 

The article I'd been reading was in 1952! I put it by the front door this morning, but walked out without it. It covers the buildup of a 270 in considerable detail, including some of the final machining on the castings. Lots of Don Francisco insight.
Cool issue...several neat T roadsters, tech on the flock of new streamliners preparing to try for 300 at Bonneville. If anybody with a scanner has it, it will be easy to find...the Offy is on the cover.