AMC/Jeep 258 Honing and Piston Fitting..... Be Careful With New Pistons !!!!

In this video I have Scott's AMC/Jeep 258 engine in the honing tank. I left .005" for honing when I bored this engine on the SIP Jig Bore. It took .060" oversize pistons to clean up the wear in each cylinder and our finished size should be 3.810" and that should give proper piston to wall clearance.
I took the first piston out of the box and the actual measurement was 3.810" so extra honing was required. I will show you the actual dimensions that I had to achieve to make each piston fit correctly.
Be careful with new pistons no matter who the manufacturer is, I have tried lots of different pistons over the years and most of them very widely in the same box.
Also remember that honing is one of the most critical steps in the rebuild of an engine. You are setting the proper piston clearance and that plays a huge roll in the longevity of the engine rebuild. Too loose and the piston will wear the bore quickly. Too tight and you will have scuffing and the cylinder will also wear very quickly. You will notice a hot running engine as well if the clearance is not correct. There are a lot of fancy honing machines out the costing hundreds of thousands of dollars, but with my manual machine I can still hold tenths and come up with the perfect piston to wall clearance every time.
Thanks for watching.

[@garyrobertson3645]

Hey Brian, your attention to detail and willing to go a little extra for every motor is what makes yours worth a little extra Really glad there’s still dinosaurs like you around 👍👍👍

[@ginacoronel6872]

Thats another engine well done! 👍 The difference in pistons was sure a surprise! I consider the 258 to be a pretty powerful engine as is, I can only imagine one modifed by you would be like! I hope the heat comes down soon, take care!

[@metalshaperJeep]

The 258 is a great engine with good torque. I like a bit more horsepower out of them so a lot of performance can be gained with cylinder head work. As you can see from the pistons it is crucial that every engine gets " hand built"

[@scottosborne9604]

Looking great, thanks for the update. Interisting about the pistons. Hopefully the heat breaks soon. Hot here too.

[@metalshaperJeep]

Engine is coming along great. pistons are terrible these days so as I tell everybody rebuilding an engine or having one rebuilt it is critical that each piston is " hand fit"

[@jimhoran5445]

👍🏻👍🏻🇺🇸🇺🇸🇺🇸🇺🇸 love what you did with the 258 head.

[@metalshaperJeep]

A lot of time is in that head, machine stumps, port intake and exhaust valves, bore for seats, 3 angle valve job, etc..... It will really wake up that 258 for sure

[@pietervanderwalt2388]

As always, a very good and informative video. Thanks

[@juanzayas7719]

Brian... The 258 CI hand fitted piston will make the rebuilt engine very durable with a very quick idle response. Juan

[@metalshaperJeep]

Lots of 258 stuff going on in the shop, assembly on a couple of them coming soon