AH Engine – Planned Case Modifications

So I’m planning to make some of the basic case mods that I’ve been reading about. Almost all of them are just general improvements to the stock engine, and are not aimed at dealing with high RPM situations and the like.

Planned Case Modifications

Mod 1 – Clearance the case greater than it is – (from John Maher Racing)

These mods are pretty basic and are a removal of case material to allow for a more equal distribution of pressure between the front and rear of the case.

Mod 2 – Oil Return Passage and Oil Drain Hole enlargement – (from John Maher Racing)

I’m not sure about my confidence to do the Oil Return Passage one yet as it requires opening a passage to allow oil to drain down to the sump area past the cam. I don’t forsee any issues with enlarging the oil drain hole by .5mm and doing a chamfered entry point there. This mod improves the oil draining back into the case and reduces the chance of oil leaking past the seal.

Mod 3 – Increasing Oil Groove Size  – (from John Maher Racing)

This mod seems to be fairly straight forward, with an increase in the lower oil groove under the camshaft bearings. This improves the flow of oil from the right case half to the left case half.

Mod 4 – Tap and plug all oil galleries (front, side, rear) – (from Eric Huelsmann)

These are pretty basic and from my research, should be almost mandatory for the rebuilding of a case. I am not going to be peening the plugs as per the link I’ve been following, but the gasket sealer I’m using should be sufficient given that this is not a performance engine by any means and the oil pressures will by typical.

Mod 5 – Drill and tap full flow oil return gallery

This is pretty much the traditional case mod for the return of oil from a full flow filter.

Mod 6 – Drill and tap for possible oil temp sensor

This is where I will install a proper oil temperature sending unit. However, I will likely only do the drill, tap, and plug at this stage as the actually sender and guage will not be necessary, or even really functional, until the car’s interior is totally finished.

Honestly, I don’t know which ones will happen other than the oil galleries and the full flowing. However, I may attempt them prior to the final cleaning and case assembly prep.

If any of them even remotely feel like they would require someone with more skill than I’ve learned then I will just skip them.