Fred's 2375 Rebuild Thread Options

[friethmiller]

[A softball question for the Ninja and/or others]

This is the cam card that came with my 2357 engine, which was originally built by Rimco/Fat (long block) a few years ago. Can someone explain why with an intake/exhaust of 448, the lift was only set to 327 degrees? I'm about to rebuild my motor and a lot of focus will be directed at piston "deck clearance" and the valve train geometry that wasn't set correctly. Thanks.

[technicalninja]

Those ARE Keith Black "silverlines".
That is a hyper-eutectic cast piston.

I was planning on using those on my build for various reasons, weight and cost being the big factors.

Those pistons can be had here
https://www.europeanmotorworks.com/pvw/034-...e+-+Keith+Black

And I might know why those didn't work...

That pin through control ring groove requires a roll pin, very small, installed through the skirt to block ONLY the lower scraper ring in the oil control ring "pack".

If you don't have roll pins in the pistons it was doomed from the start.

Those are CHEAP, LIGHT, and REMARKABLY strong for what they do. They were part of my recipe as hyper cast doesn't expand nearly as much as forged, you can run tighter bore clearances which limits how much the piston can rock allowing you to tighten up quench. I was going to ceramic coat those pistons.
I even E-mailed him to get weights on the set up. They were stupid light compared to stock and one of the lightest pistons available anywhere.

I WOULD NOT machine valve eyebrows in a cast piston!!!!!!!

The use of those would limit the available travel I had for the valve.

But they are NOT JEs...

Edit: You can have different ways of supporting the control ring pack.
383 stroker long rod pistons have a gapless extra support ring below the standard control ring pack. You have to full support the lowest ring in some manner.
Pinning it was new to me. Only time I've seen it pinned was VW stuff.
The pin locked should work fine.

[friethmiller]

Those ARE Keith Black "silverlines".
That is a hyper-eutectic cast piston.

I was planning on using those on my build for various reasons, weight and cost being the big factors.

Those pistons can be had here
https://www.europeanmotorworks.com/pvw/034-...e+-+Keith+Black

And I might know why those didn't work...

That pin through control ring groove requires a roll pin, very small, installed through the skirt to block ONLY the lower scraper ring in the oil control ring "pack".

If you don't have roll pins in the pistons it was doomed from the start.

Those are CHEAP, LIGHT, and REMARKABLY strong for what they do. They were part of my recipe as hyper cast doesn't expand nearly as much as forged, you can run tighter bore clearances which limits how much the piston can rock allowing you to tighten up quench. I was going to ceramic coat those pistons.
I even E-mailed him to get weights on the set up. They were stupid light compared to stock and one of the lightest pistons available anywhere.

I WOULD NOT machine valve eyebrows in a cast piston!!!!!!!

The use of those would limit the available travel I had for the valve.

But they are NOT JEs...

Edit: You can have different ways of supporting the control ring pack.
383 stroker long rod pistons have a gapless extra support ring below the standard control ring pack. You have to full support the lowest ring in some manner.
Pinning it was new to me. Only time I've seen it pinned was VW stuff.
The pin locked should work fine.

Ninja,

I had it backwards. It was listed as a 2375cc. These are certainly KB pistons, not JEs. My dyslexia is in full force here today! Wow! I had no idea about pinning the oil ring pack. Both support rings top/bottom of the oil scrapper are the same. I certainly clocked them away from the wrist pin opening but nothing was pinned. Still not sure what pinning involves. Some of the pics are hard to tell. I assume this would need to be ordered special with the ring set or get the rings with the solid lower ring.