Maximum Allowable Variance in Deck Height, Stock 2.0 Liter Four |
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Maximum Allowable Variance in Deck Height, Stock 2.0 Liter Four |
motorvated |
Jan 18 2020, 10:18 AM
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#1
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Member Group: Members Posts: 281 Joined: 13-February 13 From: Colorado Member No.: 15,519 Region Association: Rocky Mountains |
I'm in the process of re-assembling the top end of my stock 2.0 liter four, and I have measured deck heights as follows:
#1 - 0.036 #2 - 0.029 #3 - 0.037 #4 - 0.035 These measurements are with the cylinder base sealing rings in place and the cylinders torqued down snugly and measured with a dial gauge. To me it seems as if I need to add a shim to the bottom of cylinder #2 approx. 0.050 - 0.080 to increase its deck height to within the range of the others. I have a couple of used 0.080 shims, one of which I could add to cylinder #2 to bring it up to 0.037. I have a couple of questions about this. First, how much variance is permissible between the measurements? If the deck heights are all within 0.002 of one another, is that Ok or do they need to be exactly the same. Second, can I re-use one of my 0.080 shims or should I source a new one. And third, do I place the shim on top of the cylinder sealing ring, beneath it, or doesn't it matter. I was planning on putting it on top of the sealing ring. Thanks in advance for your advice. |
Mark Henry |
Jan 22 2020, 03:24 PM
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#2
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
That's the one I have but it also has a plate that drops in between and is keyed to the half circle cut outs you see on the bars. No need to use a dial indicator, a vernier caliper zeroed on the plate is good enough.
Used it again today, got +/- .001 on all cylinders, .041 deck no base shim on KB pistons. Little lower CR than I was aiming for with stock heads, but acceptable so they went in with no shims or head gaskets. (IMG:style_emoticons/default/smile.gif) |
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