340 piston to head clearance????

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swinger340

swinger340

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I have a 340 w some TRW 2316s that stick .015 above the deck. Found some edelbrock 65cc heads that have been planed .040. Now 63cc, but w a .039-.045 headgasket will i have plenty of piston to head clearance? Im thinking id be fine because the gaskets will be .024 - .030 higher than the pistons to start with. Any thoughts? Work fine? Or should i keep looking for some untouched heads?
 
I think some will say it be fine but it seems too close for me, pistons rock, forged pistons even more so. If you do run it be sure to let the engine warm up before getting up on the rpm's.

Why can't you grind the head for more clearance ? Use a head gasket as a template
 
dodge freak said:
I think some will say it be fine but it seems too close for me, pistons rock, forged pistons even more so. If you do run it be sure to let the engine warm up before getting up on the rpm's.

Why can't you grind the head for more clearance ? Use a head gasket as a template
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Im back and forth. Probably be fine but why chance it when for a few hundred more dollars i can get new heads and not worry about it @ all :)
 
It should be plenty of space, but what about the valves? The piston to valve clearance is determined by cam timing and to a lesser degree, valve lift.

Having the pistons out of the hole that much would make me nervous unless I was building it specifically for that much compression and that little clearance.
 
rnaz said:
It should be plenty of space, but what about the valves? The piston to valve clearance is determined by cam timing and to a lesser degree, valve lift.

Having the pistons out of the hole that much would make me nervous unless I was building it specifically for that much compression and that little clearance.
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Stock 68-71 340s have the pistons like this. He has a short block already together and is looking for a set of heads that will allow the use of the pistons. I agree that the valve clearance is a concern. Cutting the heads that much not only moves the chamber closer to the pistons, but the valves, as well.

And of course, there is always the issues with intake fitment, like you already mentioned.
 
Ok, that makes a little more sense, but still a concern.
 
damnimcooltom said:
Stock 68-71 340s have the pistons like this. He has a short block already together and is looking for a set of heads that will allow the use of the pistons. I agree that the valve clearance is a concern. Cutting the heads that much not only moves the chamber closer to the pistons, but the valves, as well.

And of course, there is always the issues with intake fitment, like you already mentioned.
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An uncut set of heads would make for no issues. Lets make a deal.
 
You could use the fel pro 8553 head gasket....those are .053 compressed...

some insurance for clearance.
 
If that head has the open chamber on it, then, IMO, you don't have much to worry about. Make sure the chamber is larger than the bore. It's not going to be close even with .040 cut from the deck or an .039 gasket. If the remaining recess is more than .015... MILES of clearance. :)

I've taken a set of those 65cc heads and surfaced the entire open chamber part out of them. It took a lot of cutting!
 
You have plenty of clearence. The pistons are tall, and you should not see more than .005" rock at operating temperature. I routinely run shorter pistons at .030 wit no problem. Valve to piston clearance will need to be checked when you have you cam in that block. But again, I see no reason to think you won't have a ton of room but until the cam's degreed and in, you won't know.
 
65cc are the open chamber 60179 ede's last i knew...

I'm out.
 
Open chamber. Go for it. Use felpro 1008 head gaskets.
 
I think im going for it. After talking w the seller his 340 the pistons were .018 above the deck. He had no problems w the 1008 head gaskets. These heads only have 6 passes on them and he decided to go w w5s. They are stage 1 ported and can be had for $1100. Does that seem like a fair frice? He was also running a .625 cam w 1.6 rockers. im only running a .555 w 1.5 harland sharps. My compression will be around 11:1 is that to high for pump gas?
 
Aluminum heads should be ok with 11 to 1

There should be a little of the open chamber left i would guess. I know i had my mopar 576 heads milled .030 and there was lots of the open chamber left, i believe around .030 the ridge was
 
Off the Edelbrock site:
"Designed for non-emission 1968-73 340 c.i.d. Chryslers, RPM Chrysler 340 heads have chambers machined .060" for clearance with early high-compression engines"

So cutting .040 off still leaves .020" of open. That's plenty.
 
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