Hello Guest, welcome to the initial stages of our new platform!
You can find some additional information about where we are in the process of migrating the board and setting up our new software here
Thank you for being a part of our community!
What tool are you using to cut the valve seats? There seems to be a lot of vibrations and poor cut quality, and these will not seal. Lapping compound is not the way to make them seal either.Question, I have been cutting the seats. The valves are the same size as the seat. So when doing 3 angle valve job the outer edge of the seat would be 30 degrees. But can it do any harm when it is already within the size of the 45 degree angle of the valve itself? Do I need to cut the first of three angles outside the seat? Then the valve would be deeper inside the head as well?
What valve seat cutting system are you using?Thanks a lot for the extensive advise!
My eyes see nicely cut valve seats. My phone camera sees shitty ones for some reason.
They really aren't that bad at all.
Edit: about the valve guide on the exhaust side, this is how I also did it on my b20 head. How should I correct this?
OK, so that is (should!) use a tapered pilot for the cutter. When the pilot is installed a guide with an angle cut on it, the pilot will deflect to the "low" side of the pilot. So you will need to side-load the cutter the other direction. A flashlight and a straight valve will help you see how concentric the valve seat is.I cannot say this in public
Edit: similar to this,
Volvo seats aren't what I would consider "hard", they are relatively soft in the grand scheme of valve seats.Yeah so it is a brazed one from China. That's why I said I cannot say this in public.
So it is cutting through the hardened seats quite well I must say. It also comes with a kind of surfacing tool for after the cutting. But it doesn't work that well.
So the finishing needs to be done either by lapping or I need to find another way.
How about the valve guide? Do you think it will be an issue?
Edit: but the pilot is straight and fits nicely in the guide. So that shouldn't be to much of an issue right?
Edit2: this is what the thing looks like
I haven’t ran your combo through my CR calculator, but just check your math and numbers.Picked up the engine yesterday!
Looks so nice after boring, honing and decking job!
Fitted one piston to measure the deck hight. Came up with 0.2mm above the deck.
They have a dish of 25cc
So looks like I need to shave the head like a lot!
Measured the head came up with 56ml.
For 1 on 11 I need 43cc.
So looks like I need to cut the head down like 2.5mm at least.
Is this a smart thing to do? Or should I do a bit less?