V-12 Engine into 308 Build, over on Grassroots

I follow this thread every day. Excited to see what is next. This is not what I like to see. So sorry to see the problems. However however whatever you take to keep such a positive attitude... please share!!!! I'd be balled up in a corner. I'm impressed with the skill, knowledge and tenacity you have in doing this build. Its the kind of stuff I'd love to do, but I know I don't have the knowledge, skill, or temperament to even contemplate. All the best going forward.

 

The valves and all the valve train are Kibble White and mostly all NLA. Ferrea has similar valves so likely that is what I'll use.

The why does a head fall off at 1500ish rpm? Did the screwy timing damage the plug and the ceramic fell off and help the valve open? I had just cleaned them so maybe? Or something else got in there? I don't know.....but now I can weld the port and return oil leaks.

 

+1

 

Well that sucks (NLA)..
KW is good stuff, so that's wild.
I like superformance, since they specialize in Euro vehicles they've got an extensive catalog of "little" valves. Many a custom used a longer then needed stem and we just had the machine shop cut to length and add new keeper grooves. You could give them a shout, talk to Willy.
Teardown will be more informative... Man that's a bummer.

 

Yeah, these were blanks that I cut to grooved. KW used to have an amazing selection for custom builds but it looks like they've dropped it all. Ferrea has a close replacement, a bit pricier but the right sizes, very similar profiles so should be fine. I used their exhaust valves when I damaged a couple on assembly last year (?).

Why though........as you say, maybe I'll see something on the tear-down.

 

Oh, as weird as it sounds when I started grilling the mfg on the rpm ranges our engines were going to spin to, they couldn't guarantee that the valves would survive long term. Odd i thought, but then again running the numbers for the forces involved it gets interesting above 8k, esp when going for 11k+ . Superformance though has a decent selection of race valves for motorcycle that will see those speeds so that's why I went in that direction. Valve stem was smaller but that's not a deal breaker for all the custom work on those builds.
Valve train harmonics with spring rates, spring design, ramp rate etc.. I built many a spread sheet to track all that. It's what drove the 11k+ valve train to a custom beehive spring and lots of Ti.

I gotta say, winding that engine out on the Dyno to 10k was beyond pucker factor 11.. God what a stressful week that testing was!

 

Supertech... No idea what it kept getting auto corrected to superformance...

 

Well here's a set forward, I have a piston. I don't recall exactly why I have it, the skirts scuffed a but so it probably measure undersize so I replaced it before I realized the3 bores were going to be oversize and I needed to coat the pistons and this one will certainly coat to fit just fine.
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So bloody close..