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As I said I am not an expert and I do respect thoughts different from mine as I have been wrong more than once.
Of course check with Mode and other pro tuners before making any major changes.
My understanding is the longer the stroke the more difficulty. A 2.0/ 2.2 can be made to work to 8 k w/o working the oil supply circuit. A 2.7/3.0 can do about 7500...
For most cross drilling is just another bragging point. However, cross drilling or adding a center supply is a proven part of extending the RPM on a Porsche motor. Most oiling related failures happen in the center two rod journals as it is difficult to get the oil that far down the crank under the forces involved.
As I noted the oil relief circuit should be investigated as that determines the peak oil pressure. I have not heard of anyone else discuss this before but I lost a very expensive cross drilled crank because the builder overlooked this and I was not even up to stock pressure.
You can imagine the sick felling I had in my stomach when the next day before a planned visit to the track I took my new 2.4S racing motor out and quickly started hearing the deep down knock that comes with pounding out my #4 rod bearing, notching a cylinder and pounding a head. For the second time!
I suspect A VW with a supply at each end is in par with a 6 cylinder Porsche crank with a supply added to the center.
I wonder what the GT 3 motors do?
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