I'm building my first slant and have been for some time now . My machinist just got done taking .100 of the head and .015 off the int/ex surface it was pitted real bad. He thought I did a great job for my first set of ports nothing fancy I just used a little sense and gave things a rolling surface to flow. But the bad thing is he thinks It's kind of silly to put this head on a slant thats .06 over but .200 in the hole actually he said it would be a shame and I have to agree with him. I'm not in a hurry to get it done as you can tell by my posts over the last six months. whats inportant to me is I learn how to build a engine and do it correctly. Hers some
more facts
Offy intake
4 Barrel don't know what size yet
Duel ex manifolds
1.7 int/1.44 ex valves
Cam P4286678 I also have a P 4286681 but Doc thought this might be alittle to much cam for a street strip mostly street car.
Erson sersons and retainers
It will go in a 74 Duster 3 spd rearspd rearendknown
So give me a little in put should I mill the block or go with domed pistons ? I f I go with domed pistons how much can I expect to pay and were can I get them. Thanks to all

What kind of fuel are you running this thing on?

On a 225, you can push the compression ratio higher than 11:1 by using flat topped pistons and zero deck height. Domed pistons often make for worse combustion, so I'd much rather have a flat topped piston than a domed piston if the compression ratio were equal.

I don't see any reason to run domed pistons in a pump gas slant six.

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"Mad Scientist" Matt Cramer
'66 Dart - turbocharged 225
My blog - Mad Scientist Matt's Lair

I will be running it on pump gas. So what your saying is keep the flat tops and deck the block. Who supplies shortened push rods for a slant I already took .100 off the head so I imagine I will need them.

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Official Cookie and Mater Tormentor.

Time to get some actual measurments.
What is the decked head chamber volume? (in CC's)
Is the piston really .200 down in the block? (not .195 or .205?)
What head gasket will you be running. (compresses thickness)
Make a cam choice and we can now estimate the best static compression ratio to run and deck the block to get the stactic compression ratio to support the combination of parts you have.
DD

Not necessarily deck the block - you can use 198 rods in a 225, or custom pistons, to move the pistons up in the bores as well. With that much off the head, you're likely already in the 9.5:1 or so compression range as it is.

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"Mad Scientist" Matt Cramer
'66 Dart - turbocharged 225
My blog - Mad Scientist Matt's Lair

Do you need custom push rods with .100 off the head? I took .090 off mine.

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'72 Duster 198 stock cam, 3:23's Hookers on jack stands for 8 years in the driveway
'79 Maxivan 360 Offy Qjet Comp RV cam/rusting in the driveway.
93 D350 160HP Cummins Auto Dually Clubcab needs a injector pump
2005 Golden Couch Buick

The head is still at the machinist hopefully I can pick it up in the next couple of days then I will cc it again. I will also check my deck height again over the weekend. I did it once but I can't find my note that I wrote it on.. For a head gasket I'm using a fel-pro.. When I get all my facts gathered up I will post.