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> Installing Cylinder and Heads, Minimum deck height?
OU8AVW
post Nov 16 2013, 03:24 PM
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My gasket kit came with one aluminum gaskets for between each of the cylinders and case. The 2nd hand cylinders I bought had multiple gaskets stacked in this space. I assume only one gasket goes there as that is what I see in the Raby video.
Correct?

Also, the kit came with metal gaskets that clearly fit between the cylinders and heads. I'm not used to seeing this used.
Skip these?
How concerned should I be about deck height now?

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Cap'n Krusty
post Nov 16 2013, 04:05 PM
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You need the cylinder base gaskets. I usually put a VERY thin coat of either Kuril C or Permatex "Ultra Blue" on them. (I don't apply the sealant until I'm ready for the final assembly.) You need to determine the combustion chamber volume and the volume of the cylinder above the piston when it's at TDC. Adding those numbers gives you a plugin for one of the charts that are floating around out there. I recommend (and always use) head gaskets, others don't. If you choose to use them, they'll need to be figured into the calculation. The process is important, and not very simple.

Good luck!

The Cap'n
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Mark Henry
post Nov 16 2013, 04:32 PM
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For me it's up to 3 shims can be used between the case and each jug (everything must be equal/same) . I don't use the head gaskets.
You must do the CR math to know how much shim to use, no guessing on this step.

On doing this right it seems that most cases now need to be decked...the bores machined flat
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OU8AVW
post Dec 10 2013, 07:42 PM
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Ok, I measured/CCed my heads. 62.5cc across the board. Looking at the calculators I should see a CR of around 9.1:1 with a deck height of .045.
Thoughts?

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Java2570
post Dec 10 2013, 08:59 PM
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Did you double check the CC'ing? That seems higher than normal....I'm thinking 58cc is stockish?
Unless some machining was done to make the chamber larger?
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OU8AVW
post Dec 11 2013, 04:27 AM
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Well, they were all the same. and I did do one twice.
I think I need some serious shimmage. Sounds like closer to 8.5:1 CR would be better....
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OU8AVW
post Dec 11 2013, 09:36 AM
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Correction to my CR. Looks like 8.26:1 will be attainable with .045" DH....

My next step is to get the custom spacers to finally set my deck, then I can install the heads. I think the thing to do will be to make an adjustable pushrod and use it to set the geometry. I have machinist friends who can help make this. I have Cro-mo pushrods so I can set the lifters to zero lash. I'm not used to this as I've usually dealt with Type 1 motors and stock Hydraulic lifter Type 4s.

I'm finding that .045" is around the minimal deck height. Correct? (IMG:style_emoticons/default/confused24.gif)

If I can achieve this then my CR will be 8.26:1. Kind of low but then again I might be a little off on my measurements. I made a tool that helps measure this. One issue I had was that my pistons went .01" prod of the cylinder when I fist installed it. This means that I will need the custom shims or use a head gasket. Not sure what I'll do next. It usually takes about a week to sort all the info/opinions before I make a decision. That clock started last night (IMG:style_emoticons/default/blink.gif)

So, Crusty says use the gaskets, Jake and Mark are on the no gasket side.
Gaskets or no gaskets?
Should I do a poll?
Should I buy a poll and install it in my bedroom? (IMG:style_emoticons/default/blink.gif)
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stugray
post Dec 11 2013, 09:47 AM
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My latest build I went with a .035 deck, ho head gaskets and my Comb Chamber measurements gave me ~58-59CCs.

I also took material from the heads when I had them cleaned up for a final Comb chamber closer to ~54 CCs (exact numbers are at home I can check later).
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OU8AVW
post Dec 12 2013, 11:58 AM
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QUOTE(stugray @ Dec 11 2013, 07:47 AM) *

My latest build I went with a .035 deck, ho head gaskets and my Comb Chamber measurements gave me ~58-59CCs.

I also took material from the heads when I had them cleaned up for a final Comb chamber closer to ~54 CCs (exact numbers are at home I can check later).


I'm pretty sure I was getting 62.5. I used a bosh plug and a 30cc syringe. I filled it twice then added another 2.5cc to fill the bubble. I may be off .5 cc but not 4cc. Am I doing something wrong? These are late model 2.0 heads I'm using....
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stugray
post Dec 12 2013, 12:02 PM
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I had a syringe that was exactly 60cc from a veteranarian supply.

I always stopped just short of using all of it.
You can also seal the acrylic disk down with some wheel bearing grease. That might help.
I put koolaid in the water so I could see it better.
Some use power steering or AT fluid.

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OU8AVW
post Dec 12 2013, 12:08 PM
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Here's the numbers I'm plugging in giving me a 8.26:1 CR. Look right?

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OU8AVW
post Dec 12 2013, 12:10 PM
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I'm using power steering fluid and chasing the bubbles....
I'll do it again this weekend with cool aide. That sounds more fun. I should be able to get a 60cc syringe too.
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stugray
post Dec 12 2013, 12:22 PM
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That deck height is incorrect. Mine was.035
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OU8AVW
post Dec 12 2013, 12:49 PM
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QUOTE(stugray @ Dec 12 2013, 10:22 AM) *

That deck height is incorrect. Mine was.035


Inches, this is mm (IMG:style_emoticons/default/biggrin.gif)
Your numbers give a 9.5:1 CR. Rather high?
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stugray
post Dec 12 2013, 01:41 PM
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Ahhh yes.

And yes I want the CR high. Carbs, race car, High altitude.
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gothspeed
post Dec 12 2013, 02:39 PM
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QUOTE(OU8AVW @ Dec 12 2013, 10:08 AM) *

Here's the numbers I'm plugging in giving me a 8.26:1 CR. Look right?

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Is this calculator web based? what is the link? (IMG:style_emoticons/default/smile.gif)
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OU8AVW
post Dec 12 2013, 05:47 PM
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CR Calculator
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OU8AVW
post Dec 12 2013, 05:56 PM
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Anyone wish to chime in on the minimum deck height on these motors?
I'm seeing .030-.045 as the minimum.
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stugray
post Dec 12 2013, 06:00 PM
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I read once where Jake said that less than .030-.027 (depending on parts) and you are rolling the dice, but I cant find the thread.

I had mine at .025-.027 at the end of the last build & got nervous and spaced it to .035
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MrHyde
post Dec 12 2013, 06:24 PM
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I used a 60cc syringe from a nurse friend and got 61.5cc's on all four chambers. The only real work done on the heads was oversized exhaust value, new seats and some exhaust port tweaking. I used water and ATF to measure with a bosch plug as well.. measured many times and got the same numbers..
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