Should this casting line in my engine concern me?

[bhays]

I am rebuilding my engine and trying to learn engine building as I go. A friend is doing his side by side with mine and a friend with years and years of engine building experience is teaching us.


Tonight we finished tearing down both our motors and pulling out the rotating assemblies. We did his while our 'teacher' was there, then pulled mine apart after he left.


In my block, under the cam journals there is a line of rough material from almost the front to the back of the block. It seems to be just leftover material from when the block was cast, but the other engine was totally smooth in that area.


Is this anything to be concerned about? Should I try to clean it up with a die grinder or does it really even matter?

 

[rsanter]

It's no big, just where the two halves if the casting core originally were put together.
How much horsepower are you going to make?
On the race engines or high HP engines I would build I would use a dies grinder to knock down all sharp edges ( so I don't scrape myself working on it) and knock down all casting lines as those were areas of potential stress risers. For a regular street build it'd not needed

Bob

 

[KLRCraig]

Nothing to worry about just grind it out of there.

 

[sberry]

I like to smooth up the casting on the outside if its something I am going to keep. When it isn't littered with burrs and sharp blind edges so much nicer to paint.

 

[BillK]

B,
I wouldn't worry about it. In order to do it correctly you need to take the cam bearings out so that you can clean up all of the metal dust you will make. I bet half of the engines we see are like that. Hasn't caused a problem to this point ... leave it alone.

 

[bhays]

That's good to hear. I was just a little concerned because the other engine we are doing was perfectly smooth. I am trying to learn as much as I can going through this rebuild process and had no frame of reference to know. Thanks for the info, guys, I really appreciate it.

 

[1SlowFormula]

Do both engines have the same casting number, it looks like yours is a run of the mill "207" 4 bolt main SBC built from 80-85 and normally used in trucks but were in some cars as well. But to answer your question, I wouldn't be concerned of the casting line there, as long as the same one on the top side is smooth for helping oil drainback in the valley. Only thing about those 207's is that they were OK stock, but if you try and bore it too big you might run into thin walls and if you're planning on going bigger than .030 over then you should have it sonic tested first.

 

[bhays]

I actually bought the motor as a Jasper Performance rebuilt motor. It was setup as 325hp and is already bored .040. I never even fired the engine as it sat in a neglected project car for over 12 years. II have a fully chromed tuned port setup and serpentine for it so I want to use this engine rather than just getting an LS. I am, however, going with a twin rear turbo setup, so I needed to replace the cast rotating assembly with forged. I really wanted to learn to rebuild an engine, so I am using it as a learning exercise. From what I've see .040 over is ok for boost as long as the compression ratio is kept down below 9:1.

 

[bhays]

Oh, and to answer the question you originally asked, the other engine is a 2 bolt main.

 

[gayler]

I wouldn't worry about it. If you were making 100hp then I would grind them down.