Looking at your log are you really only running 9* of total advance at 20psi? On pump gas I run 18* over 5500rpm and 14* ish throughout the midrange, while running a tapering boost curve from 17-20 psi as rpms increase. Your timing especially for running ethanol is really low, not sure if that contributed to this issue but high egt from severe lack of timing could cause a valve to melt. Fwiw I run OEM valves all the way up to 26 psi with no issues no super tech I'm disappointed.... Plus you said it's not even SS that's shady.

 

Yeah this is my first ever ignition table that I've really tried to put together honestly impressed on how long this head lasted, at least I didn't go the other way and melt my bottom end. I got no pre exsisting knowledge of roughly where the ignition values should be. Given the research on high boost tables I did on the internet, I tried do what was safe but I guess I was too "safe". Is the shape of the curve from 3-7k at mid to 20psi look right? Maybe its time I fold and pay for an Hp academy course or something lol. Or just raise the timing numbers if the curve seems alright. All ignition values at 10psi of boost or below were ripped straight from my friends stock motor nb so that probably also needs a fine tooth comb.

 

Well, very high heat can lead to certain blends of stainless becoming magnetic. Inconel for exhaust isn't a bad idea for a turbo car, but not always necessary. Inconel intake valves seems like a waste of money IMO. Also, it is entirely possible that the lash was in spec (maybe at the tighter end) but given the discussion of your ignition timing, your EGTs were likely through the roof and the valves may have just gotten way hotter than intended and expanded to the point that a few of them got to negative lash and were unable to contact the seats. But once cold and shrunken back to normal size, the lash may be within reason. If it was purely heat expansion causing the issue, its a vicious cycle, because once they stop contacting the valve seat, they lose what little heat rejection ability they had and the edges of the valve start to erode rapidly, as you saw.

TLDR: This was likely user error and not a bad set of valves (sorry to be blunt, don't mean anything by it)

 

In my opinion for 20psi and e85 you should be running over 20*. When I say 20* that's after tq peak, although with e85 you can get away with a lot more timing. On my car at say 22psi with 100 octane (still not as good as e85) I'm running 14-15* of timing through to tq peak which is usually around 5000-5500rpm after that I ramp it in and end up with 21* at 7200rpm. I can try to take a picture of my timing map if I can get this old XP laptop to turn on lol. I have an ancient Hydra ECU so I have to use this old *** laptop.

Tq peak is probably where the engines VE is highest and then drops after that so the added timing helps prop up the power to redline.

 

No, thank you I appreciate the honesty. I didn't know about the heat turning the SS ferrous (if im understanding that right) which would absolutely make sense and also point to the intake valves being overheated as well. I am still curious about only the intake valves on 2&3 being tuliped and not having holes burned directly though the face unlike the 1 exhaust valve on cylinder 2 , was that just because of too much heat and more or less "forging" the valves as they slam up against the seat and deforming them? I thought that could only appear when dealing with valve float. I got the Inconel intakes just to be safe, as I'm going to continue tuning it myself as I try again this time around and give myself some more leeway. Also kinda just wanted to ball out on them tbh.

 

If you could get a screenshot of the table I would greatly appreciate it. Even though the software is old a table is a table . Also out of curiosity is this at 9:1 compression or higher? Im sitting at 9:1 on my motor

 

My pistons are 8.8:1 but I've had the head decked twice so it's probably hovering around 9:1. I'll fire up the laptop tomorrow after work. Also, I remember when I was building my head I wanted to go +1 valves but it was around COVID and they were all sold out. But I wanted to go with Manley valves people have had issues with the supertech in the past. Heck I'm using OEM valves and they are solid.

Found this on my phone. This is like 4 years old but the tune hasn't really changed much if at all. The Hydra has a lot of resolution for the timing map. Keep in mind this is with me running 93 octane with a VP octane booster that brings octane to 99-100 octane. You could get away with more on e85.