350 4 bolt main

I recently purchased a block and sent it to machine shop and had it worked bored,cam bearings, cleaned etc. When i got it back the #8 cylinder wall a spot of rust that was still on the wall this spot is about 7/16 from top of cylinder. You can feel this spot when you run the tip of your finger over it but when you drag you nail across it does not catch or grab on that spot. The machinist said it would be fine to run because the oil ring would not get to it but my question is do you think this cause problems with my compression because this is the exact spot were there the top compression ring stops. This spot runs around 3/8 of the cyclinder wall. Does it need a sleeve or junk it or Go with it. Looking to build a 383 425 to 450 hp and 460 tq street machine no racing. Thanks.  

with that kind of output.. most builders really don't want any spots in the cylinders...

be sure that when you take a block in....     that you write down the casting numbers.. write down the RPO and partial vin number on the right front deck surface...   and mark your block somehow...  then take a picture of the numbers also...

so you make sure you get the same block back..  there are usually piles of blocks that have to be bored to .060 to clean them up properly...      i used to get deals on them from the engine builder i worked at...   nobody really wanted them...  i did not care...   i also used 30/30 cranks...  oh.. they were forged... got a great deal on them..  i did not care.. they were for me.. street motors... not race...    i also run large radiators...  so cooling is usually not an issue..

it is not uncommon to have to go through 2 or 3 blocks to get a good one...

without a photo... the experts here are just guessing...   without a first hand inspection.. the answers are just educated guesses...  

what bore size did the bore and hone it to?????     +.020  or +.030"   or +.060??


when i worked there i tried to convince the owner... to bore all the small blocks to 4.023.     and then when we needed one.. all we had to do was to hone it to the proper piston clearance..  he just could not see the time saving in it...

i also through that building short blocks... less the cam and timing components would be a good idea.. we had at one point .. dozens of cranks finished...  but had to order cams and chain sets as we needed them..   that would have really saved time... as we always had pistons and rings in stock...  i don't know.. i guess i have always thought different ...  

Post a picture of that cylinder.  
Professional hi-performance engine builder

Horsepower sells Engines and torque wins races.

I am not good with pictures on the computer can you tell how to post one on here. thanks.  

bore .040 i tried to put a pic on here be could not figure how to get it to upload The machine shop i used is honest my brother has been doing business with them for years but i did mark the back of the block just in case it came back fine. When i bought thiso block is had been to machine shop but the person that owned it let it set uncovered with no oil wiped on it and the cyclinder walls got surface rust and the #8 had a spot but the machinist thought that it would clean up at .040 . If you know how to get pictures on here i will send one. Thanks  

You have to use a up load site like photobucket.  
Professional hi-performance engine builder

Horsepower sells Engines and torque wins races.

thanks  

No problem.  
Professional hi-performance engine builder

Horsepower sells Engines and torque wins races.

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well that didn't work i will try something else  

http://tinypic.com/r/2gt5bol/4  

http://tinypic.com/r/20sit5k/4

This should be a little clearer but not as close. Thanks for the help. Look at that spot right at the top of the deck i am not sure what is going there. It is off color to the rest of the block.  

I would be worried about that rear cylinder If a customer brought that block to me for assembly and wanted to use it as is I would refuse it.
I would not use that block like that I would have a sleeve installed or fined another block and machinist because he should of never let that block go with a bad cylinder like that.  
Professional hi-performance engine builder

Horsepower sells Engines and torque wins races.

Thanks alot for viewing that picture i will get back to drawing board and take my loss i have been looking and blocks in summit so we will see. Thanks again.  

No problem you should be fine with a sleeve.  
Professional hi-performance engine builder

Horsepower sells Engines and torque wins races.