hi chev guys.. Need some more info on a motor I just bought

Bought a 69 327 for $400 totally rebuilt.. looked and ran like it did.. he said it was a "stock" rebuild... WELL !!! I pill the heads off.. 1.94
valves.. kinda a pisser but then see flat top pistons and 0.60 on em.. I think damn....can't rebore it.. so I think positive.. it is like new inside and clean as hell.. What size motor is this now that it is 0.60 and what is the compression gonna be with the flat top 4 v relief pistons... I am not teh greatest at this.. I just buy the stuff to stok for other projects(like this motor is going in a 84 4x4 :) ) hanx for any advise
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You have a 331 cubic inch engine, usually those blocks are thin at .060. You are probably at 9.5:1 compresion , but the casting number on the head would let me give a closer guess.

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I was thinking it was 336.. As for the casting on the piston, ..sorry.. :( no casting on the piston just 060. I want to bring the compression down as I am planning to run a turbo setup on this. My friend (as you did) said he assumed it was 9:5:1 so by stcking heavy cast heads 72 cc heads on it will drop the compression BUT he doesn't know the engine is 0.60 over either.. I just found that out.. Have an idea what the oversize (other than make it thin as hell :( ) will do to the compression if it is a 9:5:1 piston I thought it would bring compression up being over bored. ???.. thanx for your advice..

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On Sun, 1 Jul 2007 22:46:20 -0400, "Chevrolet"

Depending on what casting number head you have they could have different capacities in chamber in them and therefore different CR's. 1.94 heads are good heads and 2.02 heads are very rare and do not really do much more unless you get well above 6000 RPM a lot. A few words of caution here. First if those are pre 73 1.94 heads they have soft valves and seats and will not last long in a engine being run hard on today unleaded fuel. (they were designed for leaded fuel) Second and most importantly if you plan to turbo or supercharge it even 9.5 is too much. You really want 8 to 8.5 (even less if planning 10 PSI or more) if you plan to runs some boost with pump gas in that motor because of detenation concerns. Under boost when you hear serious knock it is ususally too late when you hear it and damage is done as you can melt a piston in a heart beat under boost if you get fuel knock. I would suggest that you look for some late model 1.94 heads with lower compression (bigger chamber) and with hardened valves and seat that were designed for unleaded fuel. ----------------- TheSnoMan.com
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The heads I have (1.94 1.50 ) are old but valves have been redone that is why I am using them instead of the heads that came on it.., I was wondering if the piston is 060 over does that increase compression ?.. or
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On Sun, 1 Jul 2007 23:53:34 -0400, "Chevrolet"

Has it just had a valve job or have hardened valves AND seats been installed? Yes a overbore will increase CR and in your case about maybe .5. ALso it is not generally a good idea to bore .060 over on a 4 inch bore SB as it weakens cylinders and can have heating issues and also now that I think of it, I defenately would NOT turbo or super charge it with than amount of overbore as block/cylder walls could crack or fail under boost. Boring .030 is safe limit to over bore on that block if you plan to boost it. ----------------- TheSnoMan.com
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thanx for the info. I bought some magic rad fluid... he says 10,000f :) Some guy jack sold it to me so it should handle turbo now... I'll use this in my truck minus turbo setup... Maybe I'll do the 302 sbc up for tuurbo.. it isn'r over sized yet.
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On Mon, 2 Jul 2007 11:47:47 -0400, "Chevrolet"

A turbo charged old 283 would be sweet. You cold use 307 heads on it to lower CR for boost. (you could even do a 307 too as they both have 3.875 bores and lots of meat in block and head for boost. ----------------- TheSnoMan.com
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never thunk that one... hell I have access to 2 283 engines.. Your like personal advisor :) thanx again..
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Older 283's have forged steel cranks. Most without a drilled and tapped hole to retain the harmonic balancer. Easy to add.
Al
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Good point, I remembered the forged crank but forgot about the pressed on only damper on earlier ones. I had a 67 283 I put in a 72 4x4 truck for a while (so I could keep using truck) about 30 years ago while I was rebulding and warming up the 350 for it and it had a tapped and drilled snout from factory. Not sure what year they started tapping them as I have seen them both ways. ----------------- TheSnoMan.com
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