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Discussion Starter · #1 ·
Alright, I ordered Weisco Pistons .039" over bore and 8.5:1 compression (Twin Turbo pistons) for my N/A Block. I had a machine shop here in town build the block for me, Polish crank, new bearing set, install pistons/rings/pins. Now its been 2 weeks that I actually got the block back but i was putting it on my engine stand today, when I noticed that the top of the piston was sticking out of the block a little bit. Is this Normal? I thought that the piston was to be a little below the top of the block or even flush with the block? did the guys at the machine shop install wrong size bearings? or Is everything ok?

You guys have to help me out on this!!! I really don't want to put it to gether and have the piston slap my heads and eventually break shit.

Thanks,
Kunal
 

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The Blank Man
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out of curiosity, are you turbo'ing your car? why would you lower your compression otherwise?

sorry, i don't know the answer to your question... although my guess would be someone screwed up
 

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Discussion Starter · #3 ·
Yep I'm turboing the car, I was hoping to have the long block built and in the engine by Monday and start the car on Wednesday but I don't want to do anything till I get some positive or even negative feedback from you guys. also I plan on having a second opinion from a few other machine shops, cause I'm am convineced that the guy is going to tell me that, thats how it is suppose to be.


Its not sticking out by much but none the less the piston is sticking out of the block.
 

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Head of Society of Bob
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well, I can't really answer that either. While we're on a tangent though, is it possible to run tubos on the n/a with 10:1 compression? Does it limit the amount of boost you can safely run or anything?

Good luck with your project. :)
 

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Discussion Starter · #5 ·
Hey Thanks! Well JB's car has a stock 10:1 compression block and he's running like 15 psi on 15g turbos. Just get an awesome fuel system so you can safely run that high boost.
 

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I don't know for sure but from all my experiences none of the pistons ever came out of the block even by a little bit. I would be a little worried if I were you and I would see if any of the remaining pistons came out as well. That could be a great indicator. Good Luck
 

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Discussion Starter · #7 ·
yea almost all of them come out of the block by a little bit. I am definitly worried now. This sucks. I wonder if they put in wrong size bearings.
 

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i would see if they are all sticking out by the same degree. What kind do you have what is the depth of your heads and how much clearence do you have between the bottom of the head and the top of the chamber. I would ask another machine shop for the answer before asking the ones who built it b/c you don't want them jerking you around. But then again you paid a lot of money for that engine and it should be built to your likeness. Good Luck!
 

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Discussion Starter · #9 ·
*UPDATE*

Whewww.... there is nothing wrong! Geez I was scared shitless. The way the Pistons were designed for Race engineering is that they would stick out an AVERAGE 10 thousandths of an inch. This is well below the industry standard of having the head to piston clearence of 30 thousandths.
Our stock gaskets are .050" thick and the pistons sticking out .010" on average that leaves me .040". Thats quiet a bit according to Weisco, JE, and ROSS.

I called everyone I could think of to find out what the problem was. :)

I also found at that the pistons I got are a .010" shorter in compression height. So just just imagine how much the stock pistons stick out :)

Well, everything is as planned now, the car should be running on friday w/ my TT conversion :) Thanks guys for the help.
 
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