rod bearings

[cmegga]

rod beardings

What exactly are the rod bearing and what is entailed in change them over. Aside from pulling the engine what else is should be replaced when this is done?? My shop is claiming I will need a re-boar pistons and most likley a crankshaft. It this true ??

 

[chockey]

Hey JB

I'm not a mechanic but did they do some sort of an inspection to determine that the lower half was shot. I don't believe that the cylinder walls are visible unless the heads are pulled or the rod bearings condition known unless the connecting rods are unbolted from the crank shaft. Question? Are there any other shops or mechanics that you can discuss this with before you let them do the work.

I know just enough to be dangerous but when it comes to my money I ask a lot of questions. I have walked out of some shops when I felt I was be BSed. Questions, Questions and more Questions.

Lots of luck

Chuck

 

[Bob Chadwick]

Take a look at this thread. A similiar discussion.

http://www.corvetteactioncenter.com/forums/showthread.php?s=&threadid=12418

Bob

 

[Jack]

cmegga:
Have you determined WHY it spun rod bearing(s)? Was it your foot or the builder’s hand at fault ... or a shared responsibility? As for a 383/388 upgrade being an extension of a 350 overhaul ... it seems rather simple on paper ... BUT there’s a bit more (parts-time-$) involved in even a MILD 383/388 upgrade than swapping out the crank ... got that T-shirt. My mild 383/388 grew out a situation much like you’re in today. I’d be happy to discuss particulars involved but it’s too tiresome to type it. If you’d like, private e-mail me qaferret@aol.com and we can set up schedule a telecon ... I’ll be more than happy to share what I learned.

BTW, I sourced a new SCAT cast sbc stroker crank in NOV 01 from Adney Brown awbrown@tir.com ... delivered to my door for under $175.

You can see the bores from the bottom with oil pan off. Spun bearings do not necessarily mean you also need pistons/boring.

It may be more useful to maintain continuity for this by sticking with your original thread http://www.corvetteactioncenter.com/forums/showthread.php?s=&threadid=12418&perpage=15&pagenumber=1

JACK:gap

 

[Big Fish]

Rod bearings are made .010 undersize. You need to get your crank to a machine shop where they can turn the bearing sufaces to match the undersized bearings. They can do the same thing with the crank bearings. If the crank is scored beyond .010 you may want to consider replacement. There are tons of good used ones out there for almost free. You might want to mike the cylinders to see what shape they are in after doing all the lower end (or before) and see if oversized pistons might be required. Just went through this whole program with my 75 L-48. I put in pistons that will bring the compression up to 10.5 to 1, and also had the heads re-worked with 2.02 intake valves and bigger exhaust valves, cam, yada yada yada. I think a crate motor would have cost a little more, but I'm having fun building this engine.