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Here's some engine porn....I recut the 3 new seats.

One head still needs me to deck it .010" to match the repaired head. Then cut the exhaust seats but I cleverly didn't give myself any real reference to shat depth to cut them to exactly. What I probably need to do is rough cut 1 then check its lash to see how much deeper to go, a little slow but it should make it come out right. Of course I also cleverly send away the valves so.....I will deck the head then set the mill up for the exhausts and bore all the seats to size, then I can move on the blending the seats into the ports which will all take quite a bit of time. After that I still have a little cutting to do on the new liners before they can be installed in the block so it can go for finish hone. After that I still have lots of stuff to clean up so its not like I would actually be holding on the valve for some time even if I was allowed full time in the shop...which I'm not

Setup and decked the 2nd head tonight with no problem


But having just cut the intake seats they were still on my mind which made me notice that the edge of actual sealing angle of the seat is literally right at the deck, I looked at everyone on both heads and they are all still fine but any more off the deck means recutting the seats deeper...I'd forgotten or perhaps never realized how close I set that up originally. To be fair to me these are 34mm intake valves stuffed into a head designed for 29mm valves so things were bound to be a bit tight....I have no idea what ferrari was thinking taking a perfect exhaust valve size and calling it an intake

Here's something I'm pondering. The spark plug hole in cylinder 8 (the damaged one) isn't very good. The plug had gotten smash and stupid me screwed it out taking out most of the threads. I welded as deep as I could when I was repairing the chamber and it would PROBABLY hold....but this is supposed to be the no excuse built so that is probably not good enough. The simple answer is a helicoil but that has me wondering about heat transfer from the plug to the head probably being different in #8 compared to the rest.....try it and if needed colder plug in #8? helicoil all 12? Just try it as is? not really sure what I want to do with this.....

Helicoil and make sure you let the tuner know , although I wouldn't expect the difference would be detectable at 10:1 compression.

It's like 10.7, but remember that doesn't tell the whole story. The bmep should be pretty high at 17-18 bar which is similar to many boosted engines and that is what has me concerned.

Yeah, you're moving a lot of air through it, but you're also not going to be running it down the Mulsanne straight at 9,200 RPM.

Fair. I woke up stupid early this morning so I wandered out to the shop.  There isn't a ton of space left between the valves....probably a coil would be ok.  I also put a plug in the hole and torque it to 18N-m with no problem, spec is 16...so it is probably ok as is, the bottom at least 5-10 mm of thread I made from weld is good, its the top 5mm or so that is more than sketchy.  I don't know.....so I swung the head to 21deg to get ready to cut the exhaust seats while I think.

Just build a welding robot that can reach down through the plug well to get the top few threads. It'll be a fun father/son project.

With something like a WP-25 straight torch (which I don't have) I cold probably get in there....really hard to see and the rod tends to overheat and melt off dropping in the puddle. I'm leaning toward bottom taping a hole that stops 3-4mm from the chamber and putting in a helicoil. Stock there are about 2mm of threads cleared and just a little more gains space between the seat ODs as well as ensuring the coil is trapped and could really could never end up in the chamber.

As I ponder the idea that the engine may run again there are a lot of little things to take care o, one of which is an ignition timing question that has been in my mind. Dynomation says it doesn't need much timing, like 24 degrees and while that seemed quite low that is what I put into the ECU. A stock QV is like 32 iirc and Wade just send me the TR timing which is...32. I'm a bit higher compression and a bit higher cylinder pressure but 30 feels like the right place to start. The only way to know for sure is the dyno but I'm pretty sure 30 is way closer to right than 24 so I'll make that change and honestly try to remember what else I wanted to fix in the ECU to get ready to run....maybe shot for Jan2, which is the 3rd anniversary of the first run.... and fire

This graph is state of the art 1980s 8 bit processor and emissions weirdness....other than step 9, that confuses me as its clearly more than 8.  The QV map only had 8 which is much easier for an 8 bit processor.  

So it turns out I was either smoking crack or lying or both when I said DM told me 24 degrees timing. DM actually says 33 and that is what I had set in the ECU last time the engine ran. I probably have a bit much in for cranking and idle but it looks 3/4 decent. I have no idea how it got into my head there was any confusion about timing.