Fitting pistons

[Stevie G]

Finally getting around to this long rod engine assembly.
What should I have for piston clearance on Hypereutectic pistons?
The forged slugs measure larger and fit a lot better.
I have a 4.155 Bore, what size should the pistons be?
Just wondering if I need New pistons (I bought a set from a guy who was changing his combination. Stupid place to save a few bucks maybe).

Apologies for such a basic question but I don't want to mess up a bunch of expensive parts.  If it was a 350 with $99 pistons I'd slap it together and go.

[SKR8PN]

What IS the engine you are assembling? Who is the manufacturer of your pistons?  Did you bore and hone the block with a plate installed on it?

[Stevie G]

What IS the engine you are assembling? Who is the manufacturer of your pistons?  Did you bore and hone the block with a plate installed on it?

Knew  I forgot something.
It's a 400 SBC bored .030 over.
Silvolite / Kieth Black Hypereutectics (Slightly used).
Yes, a plate was used.
I'm putting in a 3.25" crank and 6.25 Rods.
The block was already bored but I had the shop here install splayed mains.
They also had the rotating assembly for balance work.
It's been two years since they had it (I was in Hospital for a while)and I don't know if they ever checked the fit of the pistons.
I've moved since then and as soon as I find their number again I'm calling them.
In the meen time I just wanted to check the clearances so I can get this thing together.
The crank has the balance job number on it so If I got screwed on the pistons I can at least buy a new set and have them balanced to match.
Hope that didn't wander too much.
Thanks,
Steve

[Bib_Overalls]

KB pistons go in tight.  .0015 minimum I think.  They also require wider ring gaps.  Any good machine shop can measure your pistons and bores and give you a readout.  Once I had the numbers I would e-mail KB http://kb-silvolite.com/index2.php and see what they say.  Where did you get the rods?  Are you building "The Engine Chevrolet Should Have Built" described in the June 97 Hot Rod Magazine?

Glad to hear you are doing better!

[Stevie G]

Thanks!
That is the engine I'm building.
I've got Mic's and a bore gage (Ebay is good for something) I just needed to know what I was looking for as far as numbers.
I got CAT rods from a shop in NV.

Thanks for the sight link.