[gtobird]

On my last 400 engine, I blew my allowance and went full tilt on the rebuild. I was biting my tongue in anticipation of doing it again, but had something interesting happen on my current project.

I tore down a stock 68 400 YT engine yesterday to send it in for machining. I bought this engine a long time ago and it just sat in my garage with oil that I had squirted into the cylinders through the spark plug holes.

I don't have much info on the engine, but the guy I bought it from said it ran good and he thought it wasn't ever cracked open. To my surprise, when I removed the heads, the oil I squirted into the cylinders was still there. All of the cylinder walls looked very nice and of course were were smooth. I checked the pistons and they had no size indication on them, so I then did a quick check on two of the cylinders. Indeed, the block was never bored. I have yet to do a full check on how much wear there is on both the pistons and cylinders, but this got me to wondering. How much wear is acceptable to just do a hone and ring job and then reuse the stock factory pistons? Mind you, the car is only for summer shows and crusing. I just want it to run good.

It might sound silly to do a rebuild without replacing everything, but back in the day I did it several times and it worked just fine. Bye the way, the crank looks excellent and bearings were still the stock GM bearings. Still need to check it for wear as well.

Old Joe