Looking for the opinion of someone who may have built a couple motors.
Here are the pictures. I did not see these scratches until I got the block back from the machine shop.
You can see a couple small scratches, these are in cylinder 3 only. I can lightly catch a finger nail on 2 of them, they are not very long but would likely touch the top compression ring. The shop took measurements, cleaned and deglazed the cylinder. The guy is telling me that the scratches were present before they worked on it but in his opinion he did not think boring was required and if it was his own motor he would have done the same. Of course he’s telling me if I am concerned bring it back and they will bored it out. The other pia part is I already purchased piston’s to stock size when he told me the bore checked out okay. So should I spend the money to get it bored and deal with trying to return/exchange the pistons or leave it be?
in the first pic, it looks like you have scratches in the next cylinder wall too. that one scratch looks pretty deep. Don’t know how much it would affect compression, other than its not desirable. How far into that scratch will the ring sit if its tdc? Maybe throw the pic up on zilvia and see what comes back.
How easy is it to exchange parts and get it bored?
My concern is reducing the life of the ring more than anything else. I think the scratch in the other cylinder is likely just a machining mark that showed up with the camera flash, the large on is the only one I can feel by nail that concerns me. I will try to measure how far it will go to contact the ring. I guess it’s fairly easy it just will cost another 300 bucks or so.
That looks like poor machining work, and the honing job looks like they used rough stone… I’d recommend to take it back and have them fix it, they should stand by their work, and even if the scratches weren’t their fault, they should have notified you ahead of time to bore them out a touch (pretty sure it’s their fault though, looks like tool entry marks)
I would get them to fix it, although I don’t know if it would be possible without having to bore… Worst comes to worst, you can always re-sleeve the engine with performance sleeves, that way you can still use the pistons you bought, and on top of that would have a totally bullet-proof block.
Then again, I don’t think I would trust this shop to do any more work on my engine if they did something like this…
It is the ideal supply machine shop in barrie. I had someone come take a look at it who said they thought the cross hatching work was good. The scratches were long enough that they would have touched the upper comp ring so I’ve taken it back to get bored up half a mm. I’ll post some pic’s once I get it back.
On another note can anyone confirm that there is nothing that bolts to these two unused tap holes on the main griddle. I did not take a picture of this step when I disassembled the motor and I’m second guessing myself as to why there are two unused tapped holes, but it’s possible the griddle is common on the fwd sr20’s and maybe they used then.
I got 87mm pistons and dropped them off at the machine shop prior to them boring. All of the ring gaps were in spec and the same across all 4 cylinders. I also came to conclusion there is no baffle for those two unused taps.
