Changes to Crankshaft Centerline

[HRCEngineering]

Reason for this post is to see if anyone has ever encountered a problem like this.
After having the block align bored, the effective crankshaft centerline is raised closer to the deck of the block. This changes the deck height of the block. Between this, surfacing the head and deck...has anyone ever ran in to deck clearance issues with aluminum rods. Aluminum rods will stretch .045" when hot, while steel is roughly .035". With a MLS HG (.051") has anyone ever encountered valve interference? I am trying to determine if I will need to notch the top of the piston more than what it is already from Ross.

-Ray Neal

 

[GVR4592]

Most builders set the piston pretty low in the hole so you probably don't have anything to worry about. The material removed during line boring is minimal, and shouldn't affect piston to valve clearance enough to cause interference. If you're having doubt's, get some modeling clay, and check the pistons to valve clearance. Do you have off the shelf Ross pistons, or are they the Magnus version?

 

[HRCEngineering]

Since the reciept says nothing about Magnus I will venture to say they are off the shelf. By "putting the piston lower in the hole" I take it you are talking about the bore. Beside lowering the compression height (move wrist pin up) or a shorter rod I don't see what you are getting at by that. And yes, when align boring, the material removed is minimal. On these motors, this should not be enough to promote interference? What about with a 272 cam; anyone ever have interference due to the added lift? Thanks for letting me pick your brain.


EDIT:
How much piston to deck clearence do you guys normally see at TDC?