1970 340 with x heads

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Bgdude1

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Just wondering, without tear down, is there a way to tell if the pistons are below the block deck, (low compression) or above the deck (higher compression).
 
it also helps if you know what the early vs later pistons vs aftermarket look like. The early have valve reliefs on one side the later 340 flat tops have them on both sides of piston The old TRW had a dimple for the spark plug etc. Then there is Sealed power and keith black etc. If it is an un molested 70 340 short block it should have the high comp pistons with valve reliefs on one side.
 
1970 340s:

20210325_095318.jpg
 

Das more like it! Although it's a TRW replacement, it's still about the same as the 68-71 piston.

That's always been one of my dream builds. To build up a blueprinted 71 340 dead stock but with the 68 4 speed cam with everything machined to perfect spec and stick it in something light.

Never happen. LOL
 
yeah....i have a 340 with those cut down trw pistons in it....has not run 15 yrs...still a standard bore...
my 340 TA motor has the TRW flattops in ...just reassembled it last weekend and the heads are not on it yet...so those are fresh in my mind...

i answered that post with my phone and i could not see the other post....
 
Das more like it! Although it's a TRW replacement, it's still about the same as the 68-71 piston.

That's always been one of my dream builds. To build up a blueprinted 71 340 dead stock but with the 68 4 speed cam with everything machined to perfect spec and stick it in something light.

Never happen. LOL
Not to hijack but is that 68 4 speed cam available? I run the Summit 276/288 duration 441/441 lift cam in mine. I seem to think that's "close" LOL! They are also very affordable. The 68 specs are to the best of my knowledge 276/284 duration .444/.453 lift but there is a caveat that duration isn't at .050 or something.
 
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I have an old set of TRW s that aren't that aggressive in the dome probably 1/2 that height I seem to think the number is 2332 or something like that.
 
I am sure yes. They are old stock I bought the car in 93 they came with it. I had those pistons and a crane ssh 320 nc cam. I still have everything the cam is rusted and has pits though its a shame it seemed like an aggressive setup when I had it together. i wish I could still run that cam. i suppose i could but I fear the cam would start coming apart in small metal shavings as it has pits in the lobe surfaces.
 
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