Is Quench Required?

Newbomb Turk said

Ok, I’m back on my iPad so I can actually see something.

I just ran your numbers again and it looks like a 109 ICL is pretty close to centered up.

But…a 110 ICL moves the triangle so little to the retard side that I’m with you. I’d go in at 110 and send that mother.

Thats going to close the intake 4 degrees later which lowers you ECR and DCR (at whatever numbers that math is figuring DCR).

Graphing the cam timing and being able to move the timing around so I can see it visually makes it way easier for me to see what I really want.

Click to expand...

Thank you for confirming. At this point, I'm prepared to take the block back to my machinist, zero-deck it and order up a 0.039" gasket. This will net a 10.46 static compression ratio, quite a bit more than I was shooting for but it'll have a decent 0.039" quench and aluminum heads with a good chamber design.

With my cam installed at 110* ICL, the IVCA will be at 71* (actually the .006" IVCA, so it may even be a degree past that) and net an effective CR of 7.98:1 (just 0.10 higher than my iron-headed 340 that runs great on 91 oct) and a calculated cranking pressure of 162.75. The calculator I use, calls it dynamic CR, but it's essentially effective CR. I've noticed those terms being used interchangeably when they all really mean effective CR. It's based on effective stroke which is calculated based on when the intake valve actually closes.

What's a tad worrisome is the fact that @autoxcuda 's combo had similar numbers and he seemly had detonation issues on the same fuel I'll be limited to. If mine ends up pinging and I can't tune it out, I'll replace the pistons or pop the heads off and go to town with a carbide. haha. I appreciate everyone's feedback.

@Newbomb Turk - Well-wishes to you and your mother. I hope she recovers swiftly.