Sorry this topic probably has been done to death, but I can't think of the right words to enter into search function.
I current have a block,getting bored, and it will be fitted with crankshaft, pistons and rods from another engine. The block appears, when comparing it to a virgin block to have already been shaved 60 thou.
I've heard from lots of people that the pistons have a reputation of been down the bore a long way at tdc.
I know the right way would be to assembly it, measure and then surface grind, but what I'm after is whether I would be safe to ask to have it surface ground another 20 thou, so it would now be 80 thou off.
It's a five welsh plug motor, around 1970 vintage, would guess.

Please let me know if you think I would be taking a risk to go to 80 thou without measurement.( I have heads that have never been shaved )

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1967 VC Valiant

Nzpete,

The stock blocks can handle a lot of milling/decking. Some people have taken 0.200" off the deck surface and raced them. I would not worry about 0.080" total. Assuming all other components are stock, you should end up with somewhere around 8.5 or 9:1 static compression ratio with an unmilled head.

Where are you located in En Zed? I spent 6 mo in Wellington back in 2005 and travelled around quite a bit. Loved every minute of it.

Happy building,

Lou

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Home of Slant6-powered fun machines since 1988

I know it's more work, but here is what I did.
After boring I brought it home installed one piston and measured deck height.
Then back to machine shop, .091 deck and I got 10.0 to 1 compr head ession with my shaved head.
Stock TRW .060 pistons.
My had been shaved .090.

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Hyper_pak

What lift cam are You planning on running? The only issue You may run
into is the pushrod getting too long, which is more likely the more lift
you have, the cup will get close to/contact the rocker arm. Otherwise,
You're good to go, maybe a little alt. bracket modding/shimming.

yes, I’m lucky to live in the en zed. Cool little country. Lots of corners, and something amazing around each one.
Thanks for your help everyone. I was keen to go to 80 but my machinist was not too keen, so he is just going to clean it up, maybe 5 thou. Once I chose cam, and measure up, I may have to send it back in for some more maybe. Just a road car for cruising. Trying to decide on RV10, or maybe RV15. Will be running 2 barrel, auto with standard stall, 3:23 :1 diff, and will see most of its running between 50 and 120km/h.

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1967 VC Valiant