Detective work on a 440 RB.

[BSB67]

The 2266 piston has a 1.991" compression height. It will be about 0.090" in The hole in an uncut block.

With a 0.020" head gasket, uncut block and factory 906 like head will be under 9:1 CR, a 84 cc head about 9.25:1CR, a 78 cc head about 9.7:1 CR, 75 cc head almost 10:1 CR.

If the deck has been squared up, it was probably only cut 0.010 or so, and the CR numbers go up slightly. Add a 0.040"" head gaskets, the CR numbers change a little in the other direction.

 

[Brandy]

Sooo...when I remove the crank I can lay a straight edge along the mains and another along the deck and the distance between the two should be 10.725. Or less if it has been cut. Right?

 

[miller]

Don't forget, you can adjust your CR, by thickness of the head gasket. Goal is to be sure you start with straight surfaces on the decks, and head surfaces. Machine shop can check, and take care of that. In many cases, it's a needed step.
My 440 took a .005" cut on them, to get things straight.

 

[Brandy]

I intend to check with Vermont Engine on Monday to see what it would cost just to check those two things.

 

[Brandy]

Here's the heads, ready for a bath and a shave....

 

[wyrmrider]

"Sooo...when I remove the crank I can lay a straight edge along the mains and another along the deck and the distance between the two should be 10.725. Or less if it has been cut. Right?"
uh your block height is from the center of the crank, crank mains centerline- you can calculate it by looking up want the block main bore size and dividing by two and measuring your way and adding the number you just got
or use your method on all four end pistons and see if there is any difference
I have an od hone for the valves- you do want a little crosshatch to hold some oil in these unleaded days
did you cc the four end chambers in those heads yet, if not how will the machinist know how much to cut where? same with the block
you can sand the top of that piston with some wet and dry on a glass plate or steel plate and polish- does look like it will clean up put post a pic after you knock it even with some light sanding
can you reuse those pistons? (the how much ridge and taper did you (or your machinist) find with your dial bore gauge) if not save them for a different build
your cam needs are not big enough to run a com HL series, lower lift comps cost you torque

 

[oldbee]

"Sooo...when I remove the crank I can lay a straight edge along the mains and another along the deck and the distance between the two should be 10.725. Or less if it has been cut. Right?"
uh your block height is from the center of the crank, crank mains centerline- you can calculate it by looking up want the block main bore size and dividing by two and measuring your way and adding the number you just got
or use your method on all four end pistons and see if there is any difference
I have an od hone for the valves- you do want a little crosshatch to hold some oil in these unleaded days
did you cc the four end chambers in those heads yet, if not how will the machinist know how much to cut where? same with the block
you can sand the top of that piston with some wet and dry on a glass plate or steel plate and polish- does look like it will clean up put post a pic after you knock it even with some light sanding
can you reuse those pistons? (the how much ridge and taper did you (or your machinist) find with your dial bore gauge) if not save them for a different build
your cam needs are not big enough to run a com HL series, lower lift comps cost you torque

So now I’m curious; one step bigger than a stock ‘68 Magnum cam or would a Voodoo(etc) be a better bet with that compression setup for the street?

 

[wyrmrider]

Bigger How
I you end up less than 9:1 as detailed so nicely above the 68 magnum cam has too much seat duration and not enough lift
Voodoo (or Hughes) is better at any compression than a magnum cam (68-78 all the same)
question is which Voodoo which you can't answer till your nail down the compression
did I say that you do not want mirror on the stems, you want a crosshatch
put them back in with some dykem of valve grind compound and make sure of pattern (all the way around seat) b 4 you spend any time on them
if they have the right cutter they can open up below the valve job, then you hand blend b 4 assembly

 

[Brandy]

"Sooo...when I remove the crank I can lay a straight edge along the mains and another along the deck and the distance between the two should be 10.725. Or less if it has been cut. Right?"
uh your block height is from the center of the crank, crank mains centerline- you can calculate it by looking up want the block main bore size and dividing by two and measuring your way and adding the number you just got
or use your method on all four end pistons and see if there is any difference
I have an od hone for the valves- you do want a little crosshatch to hold some oil in these unleaded days
did you cc the four end chambers in those heads yet, if not how will the machinist know how much to cut where? same with the block
you can sand the top of that piston with some wet and dry on a glass plate or steel plate and polish- does look like it will clean up put post a pic after you knock it even with some light sanding
can you reuse those pistons? (the how much ridge and taper did you (or your machinist) find with your dial bore gauge) if not save them for a different build
your cam needs are not big enough to run a com HL series, lower lift comps cost you torque

Right, about the mains centerline. I will do exactly that divide by 2 and add back . I just now finished disassembling the entire block. I have two oil passage plugs that wont break loose. other than that it's ready for a bath. The bores all look the same except for one. It is seriously crosshatched, deep. I feel it with my fingernail. No measurements yet. All of the crank bearings look good, as do the journal surfaces. One valve stem with a burr. Filed it off. I don't own the tools to do all of these measurements, so I need to go shopping.

 

[Brandy]

So....with the main caps off, is the surface where the end of the cap meets the lower side NOT the center? Can I not simply rest a straight edge along the parting surface and measure from there? I mean a straight edge laid catty corner across the mains parting line...

 

[miller]

Would be kinda iffy, to get an accurate measurement. Center of the center? Maybe, if you hold yer mouth right. Or, let the machine shop tell you. They'll have the right measuring fixtures.

Off the wall ?. In the one photo, single rod/piston...are all the rods 'blue', like that one? Probably like that, from heating the rod, to get the piston pin in. Something I learned from experience, steel turning blue from heat...if the blue can be rubbed off, with steel wool, or scotchbrite, it's okay. If not, temper has been taken out.

 

[Brandy]

 

[dvw]

View attachment 602916

I'd be taking a look at the upper ring land of this piston and any like it. Let's see a picture.
Doug

 

[Brandy]

Here you go, and the crank is wiped out too.

 

[oldbee]

From that 1st crank pic it looks like the oil got a little hot & started carbonizing. And those “nicks” below the oil scraper groove(?).

 

[Fran Blacker]

Had oil passage plug stuck, allen wrench ng. Guy I took it to hammered in a torx bit in it to remove it.

 

[Brandy]

Thanks for all the help guys, I have moved on to the other 440. the 74. I have two main caps left before lifting out the crank. So far it is in very nice shape. Smooth as a baby's ***.

 

[wyrmrider]

are you mesureing your piston top to deck at all 4 corners B4 removing pistons
yes you could measure from a straight edge laid across the parting lines- do you have a 12" dial caliper? 12" machinists rule
let us know how that crank mikes out what do the bearings say as far as size, and the rod bearings
depending on your budget I've polished worth cranks that that

 

[Brandy]

are you mesureing your piston top to deck at all 4 corners B4 removing pistons
yes you could measure from a straight edge laid across the parting lines- do you have a 12" dial caliper? 12" machinists rule
let us know how that crank mikes out what do the bearings say as far as size, and the rod bearings
depending on your budget I've polished worth cranks that that[/QUOTE

Thanks for the advice. I will get to it. I have started on disassembling the 1974 MH block. This thing is bone stock and heavy duty. The forged crank looks fine, the con rods are much thicker.

 

[BSB67]

Given a choice, use the smaller con rods.