having my aq 151c block bored......30 or .60

[bigbad4cyl]

block has never been bored ,,,should i go .60 over for the performance increase i would get over the .30 over bore ,,,,i dont feel this block will realy need/take another rebuild after this one ,,,,,,so i kinda want to max it out the first time ,i always see new/used blocks on ebay for 50 bucks any way ....i wanted to have the whole bottom end ballenced ,,,but the machinest said it dosent realy need it because it has a 180 degree crank ???........also asked about having the crank jurnels line bored machinest said it dosent realy need it ...he plans on putting in new pistons and rings and some smaller parts.....any thing i can do to maximize my horsepower the first time around....up compresion ratio ,,,,,etc ....i know this head that i had rebuilt will never make it around again............also i am being charged 1000$ labor to dissasemble clean and reasemble motor ,,,,that was brought to him with head off ....in the back of a pick up....he had to pull the <br />intermediat housing and i think for that much he is going to be doing the intermideate housing rebuild as well ,,,,as i have all the parts for that ...

 

[f_inscreenname]

Re: having my aq 151c block bored......30 or .60

As for 30 or 60 over, you are not in the NHRA its a boat. You will never notice the difference. I would want to leave the most beef in the block as I could. Go with the .30 cut. <br />"wanted to have the whole bottom end balanced" Not sure about the 180 crank but I would have it done anyway.When you have the bottom end balanced they do more then just the crank. <br />If the crank is not scared up leave it alone, again keep the beef on it.<br />"also i am being charged 1000$ labor to disassemble clean and reassemble motor" If that includes the head work maybe but it still sound kind of steep but I do my own stuff. Will it come with a guarantee? If so that may be worth the extra money butt...<br /> You can take my advice with a grain of salt. I paid $800.00 for my boat and now have over 10 grand into it.

 

[Capt Ken]

Re: having my aq 151c block bored......30 or .60

The older 151 doesn't have as much meat on the cylinders walls as the later models. If the cylinders need boring, go the least you can go.

 

[bigbad4cyl]

Re: having my aq 151c block bored......30 or .60

the head work was done seperatly ......they are saying 1000 dollars labor to assemble the long block ,when i bring them the head already rebuilt ...they will set timing [easy] and bolt on head ,valve cover ,oil pan ......1000 dollars to assemble motor is what he says ,,,,,,i had a quote from another shop and they said the same thing about 1 grand ....i guess that includes the machining ,recond the rods...cleaning etc.....

 

[Peter J Fraser]

Re: having my aq 151c block bored......30 or .60

I agree with f n s.<br />Only take out what you need to clean the bore to the next std OS.<br />It is worthwhile to balance the engine. More so on big 4 cyl engines.<br />Makes em a lot smoother all the way through the rpm range.<br /><br />Peter

 

[Don S]

Re: having my aq 151c block bored......30 or .60

Also understand, that if the .30 and .60 numbers are from the Volvo marine service manual, that is is .30mm and .60mm (millimeters) and not .030 or .060 inches (Thousands of an inch)<br />I agree with going only the minimum to clean up, and purchace the pistons prior to getting the engine bored so they can fit the pistons exactly.