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are all piston manuf. base there numbers on a 9.000 deck height? I was looking at srp/je pistons and thats all I saw for a sbc. The shp blockcomes with 9.025. I thought they would have to be checked but do they have to be machined brand new? I dont want to wait untill monday to ask my machine shop. They are out of town. Thanks guys.
 

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Most all blocks come a little taller. If the piston your looking at is 9.000, then you could machine your block .015 and leave the piston .010 down in the hole. Or whatever you are trying to accomplish.
We generally zero deck everything and start from there.
 

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are all piston manuf. base there numbers on a 9.000 deck height? I was looking at srp/je pistons and thats all I saw for a sbc. The shp blockcomes with 9.025. I thought they would have to be checked but do they have to be machined brand new? I dont want to wait untill monday to ask my machine shop. They are out of town. Thanks guys.
The SHP blocks a with in .003 on there decks but look at the finish and see if that what you want for a finish as some gaskets require a smoother finish.
 

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Carl,is the finish on those blocks smooth enough for a Cometic gasket as it comes from Dart ?
 

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Discussion Starter #5
Carl,is the finish on those blocks smooth enough for a Cometic gasket as it comes from Dart ?
X2 as that what i was planning on using. Carl I just want you to know Dart should commend you for the way handle questions on thier blocks. I'm getting mine from my local shop because i try to support him. When i need a crank polished or valve job its nice to have a local shop. If I did not have a local I would have bought mine from you in a heart beat. Thanks again.
 

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Carl,is the finish on those blocks smooth enough for a Cometic gasket as it comes from Dart ?
If your using a Cometic or FePro MLS gasket I would get the decks machined just to be safe and you can dial them right in as well to your desired deck height.
 

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X2 as that what i was planning on using. Carl I just want you to know Dart should commend you for the way handle questions on thier blocks. I'm getting mine from my local shop because i try to support him. When i need a crank polished or valve job its nice to have a local shop. If I did not have a local I would have bought mine from you in a heart beat. Thanks again.

I have to say I support you for using your local machine shop as there are a lot good shops out there.

Thanks for the positive comments
Carl
 

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Discussion Starter #8
Well thanks for the replies. I got to take my lifters there monday so we can make sure the bores don't need honed. I'm going to get it decked once I figure where we are at in the hole. Unfortunately I dont think we are supposed to see my crank from callies untill mid of feb.:-damnit
 

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Well thanks for the replies. I got to take my lifters there monday so we can make sure the bores don't need honed. I'm going to get it decked once I figure where we are at in the hole. Unfortunately I dont think we are supposed to see my crank from callies untill mid of feb.:-damnit
If you know your stroke, Devide your stroke by 2, add your rod lenth and the compression height of your piston and that should give you .000 deck height and you can go from their.

Good luck with your build.
Carl
 
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are all piston manuf. base there numbers on a 9.000 deck height?

I use 9.008....for the same reason that Roman chariot dictate the distance between railroad tracks.....I just always have.
 

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Carl is a great guy, and knows his stuff also. I have talked to him on the phone a couple of times and he's helped me out greatly.
Now Carl get busy and get your website finished!:p
 

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this is all a part of the final "FITTING" PROCESS...

and it should be determined by the engine machine shop.

as said by carl / CNC...the block is "tall" by a little, but if employing a MLS or commensurate gasket as compared to a composition gasket or a compressed fiber grapite gasket... the final surface finish MUST BE TAYLORED TO MATCH...
 

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Discussion Starter #14
Ok. Dont know where you got people it was saying it's easy. My machinist/builder actaully talked me into assembling this motor my self. On my back up motor I just freshened It took me 2 days just to get the oil clearances right and now I have bearings out the ass. Finally split a set to get were I wanted. He charges 350 to assembly the shortblock but he told me you do it. He said I'm one of the few that asks questions BEFORE I screw it up. I would never tell anyone that does this everday that it is easy. Hell it takes me 8 hrs plus to file rings because I dont want to go to far.
 

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Butch
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are all piston manuf. base there numbers on a 9.000 deck height? I was looking at srp/je pistons and thats all I saw for a sbc. The shp blockcomes with 9.025. I thought they would have to be checked but do they have to be machined brand new? I dont want to wait untill monday to ask my machine shop. They are out of town. Thanks guys.
It depends on the CH etc

Stroke/2 = X + rod length + compression height = deck location height @ piston

For example,
3.48" stroke/2 = 1.74" + 6" rod + 1.26" compression height = 9" deck

This means for the piston to be flat with the deck, the deck height needs to be 9"

Now I will give you my opinion, If your using an off the shelf piston I would like to see the piston @ least .005" out of the hole. On 400 GM blocks I like to see .010"+ as I have seen better ring seal and IMO its because the 1/16" ring clearance is .0018" to .002" as this allows gas pressure to apply the ring and with the piston out of the hole its a little easier to get has pressure heading down that way than say if the piston was .025" in the hole

Just my opinion and what works for me
 

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Butch
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Same here, filing rings for me takes forever cause I don't wanna go too far.
Don't worry about it

On the top rings on say a SBC, .020" to .022" depending on how far down the top ring land is

As to the second ring I just gap them, Everytime I go bigger I get better results

On 400 SBC GM blocks I go over .040" on the second ring, Hone patterns look like the day they were honed between 500-550hp with Hardblok and no dark shadows

It shouldnt take you over a 20-30min to check and fit all the rings and you should be concerned about side clearance and back clearance too
 

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Butch
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If your using a Cometic or FePro MLS gasket I would get the decks machined just to be safe and you can dial them right in as well to your desired deck height.
^^ and Cometic is a good gasket thick or thin. Dont be scared to run .065" Cometics

I really like off the shelf stuff .020" to .025" out the hole with Cometic .065" if it doesnt have vertical gas ports
 
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