A quick question- in rebuilding a 305, do the cylinder bores usually need to be rebored as part of the process? This is assuming, of course that the block is in good shape to begin with. I was wondering if this normally has to be done on a 305 or only if there's been damage or abnormally excessive wear to the block.

Thanks!

 

305's wear out just like every other engine, when rebuilt they should be checked with a bore gauge for taper and wear to see if they need reboring, anymore than .001-.002 bore wear and it needs reboring, I've never seen any engine that didn't need reboring after it's had 100,000+ miles on it, a lot of people if they want to get by cheaply will just rehone and rering an engine that shows very little wear but then you have more piston clearance and it won't last as long as it would if the engine is bored oversize using new pistons.

 

ok, so 305s don't have a tendancy to exhibit more wear than other blocks. So chances are I'll probably have to redo the cylinder bores - I'm guessing .010 is the next standard size? What's the max you can go on a 305 rebore?

 

i was told by one of the car shops around my house that the mid 80's engine blocks are crap because the nickel content is too low. something about hardness

 

You might want to go .030 over, that's what I am doing to my 305

 

.030 is the next common oversize.

 

Not true. Lots of 305s--the vast majority I'd say--run for 200,000 miles before needing serious attention.

What do you want out of a motor anyway? None of them last forever.

 

208,000 miles on my baby and she runs great. No engine problems.----knock on wood. But if you are going to do a rebuild bore the SOB out to .30 over. Its worth it.

 

.60 over yeaaaaa 315 cubes baby. lol id say go .30 seems like that what most people do anyways. how much would a rebuild cost anyways? you can get a brand new lo5 350 with heads, damperer, oil pan, pump and all that good stuff for 1500$

 

A rebuild if done by you or a friend could be done for less than $500 easily with some intelligent shopping.

 

the actual wear of the engine depends solely on how well it was maintained.

i've seen engines with 60,000 miles on them that need a .60 bore to clean them up . and i've seen engines with 150,000 that just need a little honing and they're good to go.

just depends if the owners changed the oil, changed the coolent, didnt beat on it...etc...

the 305 is a pretty good block as far as wear goes. some of the 70s ford engines be completly shot after 60,000 miles, a .60 cleanup wouldnt even help them out. guess gm didnt tell them everything they knew about thin wall casting when they made that hei exchange...

 

how much would tyhe average shop charge to do say a .30 overbore?

 

A .60 overbore would result in 411 cu.in. and you wouldn't have any cylinder bores left, y'all left out a 0, it should be .060