JumboFett

They just got em in, but they want $100 for shipping 😕 I’ll keep trying eBay too. I’m starting to believe they get snatched up pretty quick.

They’re in Australia right?

Very cool detailed description. Re the valve seats, could they be removed before welding and replaced after?

Aha… I’d like to think any machinist/welder would be aware of this fact and prepared to deal with it, but it’s good to be armed with the knowledge to ask beforehand.

By “machined on both sides” what exactly do you mean? Like, the top and bottom? (the chamber side and the valve cover side?)

Was that the head with the round exhaust ports and the weird steel insert?

Yes, I believe the idea would be to turn a low-performance head into a high-performance variant; taking advantage of the large ports and valves while reducing the pre-ignition issues, so a flat top piston is part of the thought exercise. It’s an especially curious notion given how rare those SSS heads are, and the overall lack of aftermarket head options. Honestly, if it’s a viable solution it would’ve saved me the trouble of tracking down a 219 head, and it may help future Datsun engine enthusiasts. Nonetheless, it’s a fun thought.

Hey y’all, Just pondering an abstract thought… Has anyone ever tried TIG welding the chamber of an open head and machining it into a closed chamber? Like, someone has to have tried that… right?

Insane timing… like, I feel guilty.

For real! Maybe a broken valve or valve seat, unless the rod or piston broke sending it into the head. I’m really sorry this happened. Such a bummer!

Oh no!! Malice in the combustion palace! What do you think caused it??

I love that you just have your cam card ready to flash. That’s a nice street profile. I’m gonna shoot for a slightly longer duration with more LSA.

Thanks, I’ll shoot for that quench width, and good advice re opening up the chamber. Seems obvious, and it’s easy to get lost in the details. It will be a long rod L20B, using Z20E pistons (JE brand, SRP line). The block will be torque plate honed and lightly decked, and the piston will be flush. B86mm x S86mm The cam profile will be a regrind tailored to my needs and reasonably mannered by way of a 108 LSA, but with a .480 lift and enough duration to get me to 7200rpm. Intake will close at 66° when installed straight up. That’s great to hear your engine has held up well. Its very inspiring.

Cometic MLS would be great, but they only make L6 gaskets, no L4.

My concerns with the quench area are: if I’m widening the quench 2mm doesn’t that defeat the purpose of the closed chamber design? I plan on running flat-top pistons (forged 4032), possibly with small valve reliefs. Re the HG, these guys out in Arizona will make any size to spec. https://coppergaskets.us