I searched and found only one inconclusive thread on these 440 pistons. Apparently it is an old, superceded TRW part number? Anybody got an old TRW parts list that might be able to confirm that? I'd like to know the specs on these...

Thanks

googled it & only found "flat tops w no valve reliefs" EDIT old TRW forgings are very heavy combined with the nearly 2"CH

Are you sure that it is 440 piston? What I found suggests that it is not.

I think they are 2388 pistons not 83....83 is a chevy piston. 2388 is a low compression 440 piston with 1.92 comp height

All eight pistons are clearly marked 2383P 030. The 3s have flat tops, so no mistaking 3s for 8s. They are in a Chysler marine 440 that was in a boat and appear to be forged. I found the same references to Chevy pistons, but they are not...

2383P is an old Sealed Power number that was replaced by L2388F. Attached is what I copied from the later Sealed Power catalog on the L2388F.

TOOMANTY6 2 Could you post a page from you source forthe 340 piston L2316f ? Looking for min. piston to wall clearance ...Thanks

I have pages from two different books regarding the 2316 request. Here's one:

Here's the second one for 2316 request:

thanks for the info!

Thanks !!What year is the catologue would this be for the new coated skirts{unsure when they switched although Federal SP uses the same part number for the old non coated skirts vs the new coated . This excert states .001@bottom of shirt ?????? this clearance is more like cast clearance range even if it were taken at the usual top of skirt . {mine are NOT coated }Can this be a typo?? Others plus my machinist } tell me I need .004 to .006 clearance to run the old style TRW heavy slugs L2316 what gives ??

The catalogs are from the mid-nineties which was before they began coating pistons. Most of the forged pistons in the catalog show similar clearance. I've never used the catalog to get that number before. Like your engine builder I've always used .004 - .005. Notice at the top of the page the header does say "Minimum Clearance".

.004-.005" rings a bell from when I had a set (TRW's) decades ago. deinititely not .001", that's a floating pin to rod spec

Going from memory, I thought that my old forged SP/TRW replacements were spec for .002 to .003. Also, IIRC, guys were scuffing them up pretty bad at the lower end of the tolerance. I had mine put in at .0035. They will slap at .005 but was a commonly used. this was back in the 1980s, early 90s

I believe they are made of a lower expansion alloy than 2618 racing pistons, I believe it is called MS-75 or 4032. 0.001 is too tight but 0.035 at the measuring point called out by the manufacturer sounds about right. It also depends on what your use is. If you are racing them or trying for max hp on a dyno then 0.005 is better. But for longer life on the street the slightly tighter setting will work better.

R.