Interesting stuff. Nice work Franklin. Thanks for sharing it with us.

Really interesting, especially the modified chamber! Nice work Franklin,

Interesting to see Briggs heads flowed

Great video, I was going to port my ride on lawnmower and Honda pressure washer this winter for the fun of it using what you and the great DV have taught me. Thanks Franklin.

I've done very similar chamber work on Harley heads. Blew my mind how differently the respond to short side work vs. a standard wedge head of a V8. Of course the hemispherical chamber design was pointed out as why to me after my first flow measurements. I eventually welded up some of the chamber for compression and more tumble. I was positively rewarded with dimpling in the chamber....to a point though. I found more making the runners wider in more of a "D" shape, but leaving the roof height and expanding the runner width. Good work! You're fortunate to have a test facility available to you. I hated testing in school, but out in the real world knowledge is power.

Looking forward to a follow up video on these Briggs cylinder heads. I have built a few and would love to see your final results. Thanks for sharing Charles have a good day!

Ahhh! How am I supposed to mention Mopar on this video??? Oh wait...

Ready to get a pair of these on and see how they do on the old stocker gtr.

Seems like a wedge and hemi had this head/chamber, what were the engineers thinking, it's not a performance engine . I get it. Like the old tractors had crazy looking piston domes and chamber designs, strange shapes. The WW1 erra cars had strangeness also, I'd like to weld in between 1/4 pound and 3/4 pound more material in the chamber and ports possibly, nearly fill in the chambers and possibly move the whole port slightly . Weld the inside wall on one side, and out side on the opposite side. Allowing the port center to be moved Possibly sink the spark plug into the chambers but, or just a longer plug, after the welding, close in the chamber, and use a dished piston, maybe cut the head nearly .100" afterwards, leaving the chamber nearly 1/3-1/2 the original size. With The dished piston getting the compression to the 12.5:1 range, maybe there is a easier way to accomplish alot of the same mods, without all the welding, maybe get a longer rod . Push the piston out the bore about .050" pushing the ring up near the deck, possibly only .030" below deck. Then cut the head .030"- .045" then machine the bore into head, allowing the piston dome to fit into the head, maybe .050". That should leave much larger quench pads, after unshrouding the valves, (if they are) maybe weld in the ports slightly, I don't think id trust epoxy, possibly still use a dished piston, And do the ceramic insulation coating, ceracoat I'm thinking, on the piston , chamber, and exhaust port, and possibly the head pipe inside and out, keep the heat inside the exhaust, just be sure there is clearance, yet tight, and probably get some nitrous nozzles and a high pressure pump, and build a water/methanol kit, use a pwm controller to ramp the methanol in, possibly with the throttle , and a on off, switch, possibly run upwards of 13:1 compression, 11.5:1 atleast, it would require a few engines to work the way up to all the crazy mods,

The pattern continues, the slower the roof the faster the SSR. Charlie's Law.

Interesting chamber pressures of 260, worked with that low of octane.

Maybe get crazy and mount a couple motorcycles heads to the block. Run a timing chain, behind the cover to the head. Filling/ Welding the gap with aluminum sheets, and the only possible spendy part would be a custom piston, with a hemi dome to fit the hemi head. The power should go up a fair amount, especially if a custom cams are ground! I guess that's spendy Aldo, a couple Suzuki drz450 heads may work or a older Dr650 head, it's difficult not seeing them , the displacement is close, after what I have seen these Asian and Indian guys do to motorcycle engines and heads, it's possible to get bike leads on these engines!

I, work on allot of floor buffers, with the FS-481V 18 h.p. Kawasaki engine. Those heads, have a hemi combustion chamber. It's, funny to me. I look at the ports and say, man they need some work!😄

Cliffhanger episode?!

Would dv speedbumps help the wet flow pattern

Hey, the video cut off before the flow # can you add it in?

What would David Vizard say?

Dimples are for Golf Balls ~

Imagine that, the exhaust flows on the bench awesome.......NOT REAL ENGINE!!.....reversion WILL take place with a back cut......flows on the bench nicely, on the motor, it will suck.....just sayin, ok, i need to stop talkin, hope ya get my point..... i bet ya do.......

I dont give a CRAP about application, fundamentals here: NO BACK CUT ON THE EXHAUST!!!....lets give reversion a nice street to dirive on.......i dont car about the application, a backcut on the exhaust promotes reversion....NO BACK CUT!!!.......Charles, help your boy out.......any way to remove the exhaust backcut, with out requiring a new valve?........again, regardless of application, ICE's DONT want reversion.....just my 2 cents......cool stuff......see, this is what i'm talkin about, DONT NOT make any new vids, gear heads like me, watch ALL the tech, and have annoying opinions as ya go........we gotta get rid of the exhaust backcut........bad idea.......sorry, and thank for lettin me rant......