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Connecting Rod Caps And Bearing Question - Urgent!

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No sense messing around here anymore. Your Dad, bless his heart, has all the answers. I build many 400-550 Horsepower LT1/LT4 engines for the guys on the Corvette forums and the Impala SS forums. It's what I enjoy. Plastigauge will at least let you know if your clearances are right or not. Most times the crankshaft grinder does a great job but I have seen new cranks and definitely reground cranks be out of spec. I'd just rather know for sure, but that's just me. Also the rod bolts are definitely torque to yield. In your dad's day and certainly in my day (I'm 68) bolts could be reused. TTY bolts have been stretched a specific amount. The metallurgy involved does not allow for reuse. Think about bending a piece of metal back and forth. It will eventually break along the bend line. Same basic theory with TTY bolts. They've been "bent" once. Let your dad reuse if he wants but if you intend to drive the car keep the RPM's low. At redline your pistons are going up and down almost 100 times a second. Think of all the strain as the piston rounds up at TDC and has to stop before it starts back down the bore. Now think of this 100 times a second. That's the main reason.

It's just cheap insurance. Ask your dad if he has life insurance or health insurance. He cerainly doesn't want to use his life insurance but he has it. Same with engines. Checking things out is just cheap insurance and making sure the machinist that turned your crank wasn't hungover that day. Good luck.
 
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That makes sense with the bolts - I had no idea that they made torque to yield bolts, I assume the old man didn't know either.

And it's actually my car and my money, but he is the one with the mechanical know how - and he is very stubborn. Unless you can prove him 100% wrong beyond a shadow of a doubt, he will not change the way he does things. That, along with the fact that I just want the knowledge, is why I have been asking so many questions.

I would attempt the rebuild myself, but I am worried about screwing something up, since this is the first engine I have taken apart (as you guys can probably tell). And I don't want to take it to a shop, because it would cost a few thousand in parts and labor.

I'm almost to the point where I want to buy an old junkyard engine, throw it in the car so it runs... And completely tear the current engine down and rebuild it. Port and polish the heads, more radical cam, oversized forged pistons, the whole kit and kaboodle, so I know that it is all done correctly.
 


Another thing I just thought of - one of the head bolt heads has been sheared off - the body of the bolt still in the threads. Should I replace that bolt ASAP, or should it not be a big deal, considering all the other bolts are in place?
 
I would buy a new head gaskets and new head bolts and just redo them, head gaskets are like $30ish a piece and the head bolts are $30 or so. And I wouldn't bother with oversized pistons, you won't really see any benefit of them being in there.
 
Head gasket you need 2 of these http://www.oreillyauto.com/site/c/d...=Search_02289_1374768_3224&pt=02289&ppt=C0026
Head bolts http://www.oreillyauto.com/site/c/d...=Search_02258_1374768_3224&pt=02258&ppt=C0026

Torque specs Cylinder head bolts: 37 ft/lbs + 130 degrees + 30 degrees up-to-10/98. 37 ft/lbs + 120 degrees 10/98 and later.

And you might as well replace the valve seals and put new retainers in while you have them off, it would also be a good time to upgrade your valve springs, also new valve cover gaskets, intake gaskets, and supercharger gasket.
 


Yup just copy and past the part numbers over to advanced, I always forget that they have those coupon codes, and some times you get a gift card too.
 
Since the bolts are TTY, is it alright to torque them down to plastigauge, take them out and torque them again?

Also, which bolts exactly should I replace, just connecting rod bolts and head bolts?
 


Do you know how to use plastigauge? Everything needs to be very clean and dry, no oil on the bearings or crank for the journal being checked. You can see the notches to line up on the rods in this picture:
IMG_1697 resized2.jpg

Did any of the rod or main bearings spin? If you don't know what that means, they call a bearing spun if the little notches that line up in the grooves I circled are no longer intact.

Did you mark any of the rod caps when you took them off? The rods are machined after a cap is bolted to it, so that same cap has to be put on the same rod, if they get mixed up the clearances will not be correct.

You said you are replacing the crankshaft and bearings. Did you have your crank machined, or get a replacement? You should have the rods re-sized, or replaced during any rebuild, but it is a MUST if a rod bearing spun.

Another common problem with the 3800 is the cam bearings. They wear or get washed out which causes a drop in oil pressure, which causes the lower end to fail. You need to have some experience when building any engine if you want it to last at all.
 
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