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Discussion Starter #61
My block isn't cross-drilled but, my head is and,
the angle is 45 degrees.

Print this out and check:



:D

EDIT: OOPS, sorry Steve.
Someone has to have access to a cross drilled block.
I have a dual cross drilled head and my holes are almost straight in...90* perpendicular to the surface. And the hole seems to be about a #29 size bit.
 

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This is the top of my block(non-CB)
The holes between the cylinders are just straight holes in the deck surface.



It's not cross drilled but, may be soon.
Depending mostly on ILIKESHELBY's results.
 

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Discussion Starter #63


Dang! [email protected]#$^%$^ !!!!

The angle should go away from the center of the bore and towards the edge of the block. In the pic of previous post I am clearly drilling in the wrong direction! I went over to Chadwick's Racing and machine where they have blocks laying all over the place and even though they were all V8 engines, the cross drilled holes were going away from the cyls and towards the edge of the block. Several Asian blocks were also there and they were the same way.

I just need someone to confirm that for me! That the holes go towards the edge of the block, not towards the center of the block.
 

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Well, if you're asking which direction the holes are drilled;
The cross drill holes in the blocks start on the deck surface and go toward the outer cyl walls(Down and IN, toward the center of the block)

 

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This is the top of my block(non-CB)
The holes between the cylinders are just straight holes in the deck surface.



It's not cross drilled but, may be soon.
Depending mostly on ILIKESHELBY's results.
Well, if you're asking which direction the holes are drilled;
The cross drill holes in the blocks start on the deck surface and go toward the outer cyl walls(Down and IN, toward the center of the block)

Hang on a second!
Did I miss something here?

The lower pic of the Crossdrilled Common Block has the obvious angled crossdrilled holes but,
DOESN'T have the additional holes on that side of the non-common block like the pic above.

Anyone have any comments on this? :shrug:

I understand they're both my posts but, I think I may have confused MYSELF! :puzzled:
 

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Dang! [email protected]#$^%$^ !!!!

The angle should go away from the center of the bore and towards the edge of the block. In the pic of previous post I am clearly drilling in the wrong direction! I went over to Chadwick's Racing and machine where they have blocks laying all over the place and even though they were all V8 engines, the cross drilled holes were going away from the cyls and towards the edge of the block. Several Asian blocks were also there and they were the same way.

I just need someone to confirm that for me! That the holes go towards the edge of the block, not towards the center of the block.
ya , no give your head a shake - your doing it right

down and towards the front of the motor is right

lol I've had moments of doubt like that - it'll pass
 

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Discussion Starter #67
Double dooh!


I wonder if the blocks with two cross drilled holes are done the same and if the holes intersect at all. I really need someone w/a open CB to give is a angle reading and a depth if at all possible. It looks like if the angle was about 60* the length of the hole would need to be about 1.75 to 2" long and if drilled from both sides they would have to crisscross or intersect..
 

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Discussion Starter #71
Aren't there cross drilled blocks that are cross drilled on both sides of the cylinder? Maybe on the Shelby blocks from 87 and the T2 motors?
 

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none of mine are
87 shelby z TII
89 shelby daytona TII
and 93 2.5 turbo was a new from cryco motor in 95/6

no double cross drilling on any of those
 

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Aren't there cross drilled blocks that are cross drilled on both sides of the cylinder? Maybe on the Shelby blocks from 87 and the T2 motors?
I think that was originally intended for TII applications, but heard that was discontinued or never happened in production when bits were breaking frequently in block when holes would intersect while drilling. I have a couple 87 TII blocks in use but never noticed if they were dual crossdrilled. Don't think they were, as I think I would have noticed.
If it did happen in production, I don't think for very long.
 

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Aren't there cross drilled blocks that are cross drilled on both sides of the cylinder? Maybe on the Shelby blocks from 87 and the T2 motors?
I did a search for "double crossdrilled 2.2" and, it took some investigating but,
I read that Shelby double crossdrilled his competition cars when he worked with dodge.
Not sure if it was ever implemented on any of the production models.
If I find the information again, I'll post the link. :D

EDIT: here you go:
"The purpose of cross drilling is to reduce the temperature of the head gasket between the cylinder bores. If I recall correctly it was in the neighborhood of a 150F degree reduction. (Ed's note: 75C) This was a necessity on the Turbo II's to make the head gasket live at the elevated cylinder pressures. Originally the engines were to be double cross drilled, drilled from each side of the deck and intersected. This was dropped because of difficulties in performing this operation. All of the Team Shelby race engines and the ones I have built were double cross drilled."

That's from here:
http://www.thedodgegarage.com/turbo...ake manifolds, long rod engines & headgaskets.
 

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Discussion Starter #75
OK, here ya go I cross drilled my non-CB to have the cross drilling from the rear of the block to the front of the block like on most CB engines. I added additional short steam vents going in the opposite directions of the existing cross drilling.




 

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Discussion Starter #77
I can see the hole where the 3" hole I drilled exited the inner casting area of the cyl wall by looking down one of the triangle steam vents with a flashlight. The coat hanger wire can be seen exiting the sidewall between the three cyls by looking down the front of the block steam holes.
 

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I can see the hole where the 3" hole I drilled exited the inner casting area of the cyl wall by looking down one of the triangle steam vents with a flashlight. The coat hanger wire can be seen exiting the sidewall between the three cyls by looking down the front of the block steam holes.
That's pretty great Steve!
Great job!

You may have just changed the game my friend.
Such a seemingly simple thing but,
I'd bet the results will be incredible.

Wave goodbye to high boost detonation bro! :thumb:
 

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Before I bought a Bridgeport mill to do this on I made an aluminum block that sits on the engine block and bolted down (as a guide) I copied the angle from another block that had cross drilling in it.
All I had to do was run the drill into the guide and it put the hole in the perfect angle.
One could probably be made from a piece of hard wood .
 
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