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Finish out last night with 9 ready for finish hone....tonight should be the last night with the roughing stones and the finish just needs to look good so that should be quick.

After getting to 9 last night I figured for sure I'd be done done tonight...yeah, no, but all 12 are ready for finish and probably safe to use just as they are for finish just means a nice smooth cross hatch which SHOULD be another 10-15 minutes each.

I put the other stones in hit all 12 but I I wasn't loving the finish and realized the stones I have are 80 and 180 grit so I ordered a 280 grit set that amazon says I'll have tomorrow....so the honing stretches another day.

So....as I was wrapping up "all" the wiring, whos job was it to remind me about the nitrous button? I can't count on you guys for anything!

Is it in the shift knob with the label "Go, Baby, Go!"

Will, what alloy are your pistons? 4032 or 2618?

There is more to the honing story.  I've been only about 1/2 joking about adding nitrous for 10+ years now...but that wants the pistons setup looser and that tends to make them rattle a bit at start up.  It also wants the rings gapped looser so leak down suffers and cranking compression and idle vacuum with it....so .....

.....this build is getting gapless rings which takes the compression/vacuum issue off the table leaving rattling pistons.  My piston spec sheet says .0035" min clearance which is right on the rattle line but if the pistons were 4032 alloy it would be loose enough for mild spray....and for some reason I thought they were, but they aren't they are 2618 which is stronger but expands more than 4032 so at 0035 spray would be (mostly) right out.

As I was busy honing I was doing my normal check with a feeler gauge until its close then confirm with an inside mic because those are the tools I have.  I wasn't loving the feeler gauge feel and the mic was telling me things I was sure I believed so I bought a low to almost mid range bore gauge and took off their indicator and fitting the really nice 10th indicator I have...and yeah, the hone job was coming out terrible.




the tops were the biggest and already a bit oversize, and inch down the lowest and 2-3 thou under the top, a little out of round too just to make it more fun.

Well that s**ks.......





So I took the rough stones and cut them down to about an inch and a half in length and more rpm with a lot less pressure I got the 1st cylinder pretty good...but its now 1.2ish over my target size with a little more more left to do, so 1.5 over say.

Another buddy (aka Wade) is lending me an actual sunnen hone head.  He basically says the one I have is a POS and what did I expect using it......he makes a very strong case that felt wipers pure evil,  so they should be right when they are done just bigger than I planned.

hmmmmm...that led to a full day of internet reading.  First thing, the piston spec sheet doesn't say set the pistons at 3.5 clearance, it says 3.5 min, and that is at the very high side of there specs based on bore size, probably because of my rpm which make heat.  I set them up at 3.5 last time but all my cylinders came out scuffed.  A 308 buddy also did his pistons at 3.5 and sent me this pic





He says he things it happened when he over heated a little....but overheating is a pretty common thing...and min mean minimum, they says another 1-3 may be needed in more extreme applications.  The turbo guys set them up at 6 typically for example.



The piston makers have all started supplying pistons like these with the skirts coated with a compressible/abradable coating and saying its basically god's gift to pistons because it lets you set the actually metal to metal clearance safe then to coating prevents rock and the rattle that comes with it.  The rattle wears things out a bit faster but the big issue now seems to be it triggers the knock sensors all the newer cars have.  The coating fixes that.



All this is me getting to trying to justify using the cylinders which are going to finish at least 1.5, may 2 over my original size target.....which it turns out is a fine number and much safer than what I was planning.  and It helps me justify sending the pistons out https://www.line2linecoatings.com/ for coating.......



.......and it makes it nitrous safe. 

The lower expanding streetable alloy, so probably 4032.

I had thought about that, but decided against it... now you have me thinking about that again. Grrrr...

sorry...but if you have the lower expansion pistons and they are fit snug I'm not sure how much the coating helps much? the coating people say it does but at least the JE website was talking exclusively about the higher expansion alloys to make the case for it.

...and remember, I'm doing everything I can to be able to say "I meant to do that" about the bore size so.....