right got the block back from the engineers.
was just going in for a hone but they noticed a score so i had to go oversize to 84.5mm

few questions before i start messing about with ring gaps and doing all those.
does this hone they did on the wall look ok to you guys?

also in regards to fitting a crank girdle from a b18c4, do i use both the girdle and the bottom caps? or do i re-use my B20 bottom caps as they do not have the dowel holes in them for the brace (also they are not as tall as the b18c4 ones, you can see they are 5mm or so shorter)

 

Where did you take that block? The cross hatching looks like it is all over the place. Looks like there are some 60° some 45° and even strait cuts. I believe they are all supposed to be 60° angles with the use of a fine grit stone (400). That looks kind of rough but that could be the pictures/flash reflection. You can also see were it looks like something was skipping along the surface of the cylinder wall. It kind of looks as though they used a hand drill with a ball hone on it.



If you run your fingers around the cylinder walls can you catch your fingernail on those vertical scratches?

 

if your talking about the vertical scratches going from the top of the bore to the bottom, it looks to me like the scratches that a bore gauge would leave. i work in a machine shop and those marks looks very familiar i wouldnt worry. the ones ghost highlighted are a little more suspicious (good eye)

 

EPIC FAIL.

had a really good look in the sun just now really carefully.
most are 60 degree but i can see 180 degree hone marks in there (level across the cylinder)
also on cylinder 4 there is what looks to be missing material in the wall!

now i am ****ed. forked out **** loads on this block, another £160 quid to get it bored and honed to find the block wall has something missing from it. looks like there might have been a air pocket in the casing

gonna get a pic now

 

right the vertical lines are just from being measured, i cant get a nail in them.

the black bit below (where my finger is in the pic) i can get my finger in, its quite deep to.

so pissed off. what are my options now? re-hone else where and pray to god i get no issues due to that nick in the cylinder wall? re-sleeve?

 

That is ****ed up my friend ;(.

 

taking back to the engineers to get this sorted.

im not loosing a block which so far owns me near $1000 for their error.

anyone ever seen anything like this before?

 

its called porosity and any cast material can get this flaw. best to remove it at the shops cost

 

damn..im guessing the only way to remove it is to bore/hone the block further right??

 

you can do 85 mil on those. there is a guy on here d-rob, who built one for his dad and they had no issues.

some of those crosshatch look almost 90 degrees which would leave me to believe they plunged the hone too fast.

 

Also, bore and hone without pistons=FAIL Any shop that will do that is trash IMO.

Don't install the gsr girdle either unless you want to pay for an align hone too.

 

who wants to bet a dollar they didnt use a torque plate or dummy transmission either...

 

no...they did not.

and they did the hone with a tripod on a drill.....

*sigh* well they had a look. and said that the nip due to its location and size should not give me any problems, nor will their hone...

now. i can either trust them and if the engine turns **** up, risk broke rings and oil use and make them replace the block/head gasket/rings or any damaged pistons etc.

or try to find someone else near to me that has decent stuff that can do the block. i really dont want to go out to 85mm. i am planning to use this engine in a race series and and i need it to be reasonably reliable.

i hate living here in the uk. i bet you guys have proper machine shops round the corner from you, nearest one to me was this guy at 22miles, next place is 44 miles and so on.

 

quick note for the align hone i am assuming that the journals the crank turns in will distort or oval with a brace on them correct? or is that only likely with a gsr brace? (would i get the same issue with a full 5 points girdle?)

thanks