Purple People Eater Sh*t itself today

You can see it, but you can't feel it at all. Should I get it bored?

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RDPsmoker said:
I would run it. And not think anything about it.
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You are talking about the cylinders right? Lol

How safe would it be if I decked it and ran a stock head gasket with the stock cam, so I could bump compression a tad? I don't see it being any different than running a higher lift cam on a stock head gasket.
 
Any idea yet what caused it to grenade? Drop a valve? Or was there something else that caused the cam to shear off like that?
Hope you get it back together soon, and I totally agree with the stock valvetrain. especially for a DD truck. Ive had to do some unusual mods to get my low end power back for driving in town.
 
Snedge said:
I'd run it Mike. I can see the picture posted here better than on my phone.
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Thats the plan. I need to see if there's a stock piston setup to bump compression a little since I've got it apart. 18:1 would be a nice goal. If not, then you can send out the one's you're holding for me in the morning.

biggy238 said:
That will depend on how much material had to be removed to true the deck
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Yeah, if it's <.010, I'd like to try it.
With the stock, uncut head, as long as the piston doesn't protrude any, I should be good right? If it sticks out of the block at all, I'll get a thicker gasket.

kawi600 said:
Any idea yet what caused it to grenade? Drop a valve? Or was there something else that caused the cam to shear off like that?
Hope you get it back together soon, and I totally agree with the stock valvetrain. especially for a DD truck. Ive had to do some unusual mods to get my low end power back for driving in town.
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No I idea yet. I figure stock cam with 18* timing and stock valve lash to play it safe. Get most of my low end back.

Brandon also reminded me that with the wider non-ic bowls, my 143* injectors will probably run like ****. So I need to get those swapped out. Or stick with ppump pistons.

What are all the benefits of a non-ic piston, besides being a little stronger?
 
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Mike, you will have some piston protrusion. They all do OEM, you just need to measure all 6 so you know what HG is safe to run.


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madmikeismad said:
How do they not hit the head at all?
Maybe I'll just get the right gasket then.
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The HG has enough thickness to keep piston to head clearance ok.

For reference on my stock 95 I had around .020" give or take on piston protrusion. I used stock HG and 188/220/109.5 cam. Tight, but it all clears.


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madmikeismad said:
You are talking about the cylinders right? Lol

How safe would it be if I decked it and ran a stock head gasket with the stock cam, so I could bump compression a tad? I don't see it being any different than running a higher lift cam on a stock head gasket.
Click to expand...

If you're decking the block, take off a bit extra and then cut the tops of the pistons. It'll reduce the bowl volume and increase compression.
 
The top ring is probably a little lower to help shield it from the heat.
does that piston have a higher squish volume than standard?
I ran 18* for awhile on mine but 14* timing and 155* cone injectors are a good combo for low end performance .
on the top end? not so much. Its a slug like youd expect.
 
Tate said:
If you're decking the block, take off a bit extra and then cut the tops of the pistons. It'll reduce the bowl volume and increase compression.
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Is there any concern then with top ring land height from crown?


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Depends on the piston. Some vary from 8mm from the crown to 14mm. The ones I bought with this intention is 14mm.
 
How much would I want to take off the piston? As much as was removed from the block? And then run stock thickness head gasket?
I would also be losing some displacement this way right?
And be able to run a little more timing without spraying outside of the bowl?
 
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So lets say I'm running .020 over non-ic pistons, block decked .010, stock head gasket, and pistons shaved .010. What would that put my CR at?
 
From the numbers I can crunch, you're only looking at .1-.2 increase in CR with .010 off the piston and block. You'd have a higher increase by running tighter head to piston clearance, like decking the block and running the piston unmolested. Going from a .038" clearance to .028" bumps it up by 0.6.

Anyone have the volume from the valves being recessed in the 12v head? Or valve diameters and typical recession? Could make my numbers a bit more accurate. I'm just guessing right now at that figure.
 
madmikeismad said:
How much would I want to take off the piston? As much as was removed from the block? And then run stock thickness head gasket?
I would also be losing some displacement this way right?
And be able to run a little more timing without spraying outside of the bowl?
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If taking any off the piston. I would just take enough off to get it within spec of piston protrusion.
 
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