B_Swapped93

I pulled the engine to clean everything off, well there's rust and some scrapes that my nails DO catch , right when I pulled the engine this rust was not there. Seeing as up until then I was driving the car, so what caused this? the block was supposedly a JDM 98 spec R block but the back of the block read P72 the pistons and EVRYTHING else read P73 tho. my though is incorrect ring gaps gouging the wall as the piston was put in, seeing as it looks like someone took a jdm "gsr" block and threw P73's in .



Each cyl has this but this is the worst the the other one is almost the same and #2/3 are the best

Runnerdown

The blocks are shared between gsr and type r. P72 and P73 can be found as well as other codes like PR3 cyl head, don't get too wrapped up in it. We don't know how the rust got there, it happens quick when cylinders are exposed to moist air or water

B_Swapped93

ok found that out, after posting in the R section. So is that cylinder "ok" i'm worried about the scrapes it pushed just over 240psi in each one, with maybe 5 psi variance.

B_Swapped93

upon further inspection the scrapes were just dirt and rust...the rust came off as soon as I rubbed engine oil on the walls and spun the crank a few time.

Pro-SeriesFab

You got it . . . its a decent amount of rust.

Usually that stuff will clean up well with a fine scotch-brite pad or a 320grit hone depending on your ring material.

I'm actually tearing down an engine right now with the same deal, alcohol was left in the bores and with it being pretty hygroscopic it collected water and lightly rusted the bore where the water sat.

Unless its a max-effort N/A pro-stock style engine, cleaning it up some will be fine.