Milling a predator 212 head.

[DieselTech]

Well since @rusty.western.flyer posted sprocket fab with a router. Figured I would show this! I milled .050" off of this head with a router.
It was not even a high dollar router bit, $18 American Vermont carbide bit.
If i was to do it over i would have used my ½shank router & 1/2" thick router base plate. It milled super nice, & was within .001" or less across head gasket surface.
If you have never used router tape, get some it works good for routing, milling, all kinds of stuff.
Anyhow here is a couple pics.

 

[rusty.western.flyer]

Yeah, 25 thou would be a bit of time on the belt sander lol.

 

[michael whiteman]

Ya might want to put a piece of clay on the piston and check the valve clearance. I'm sure there is more than enough. Nice job on that head.

 

[Cannonball3]

I used to run a pretty hot Briggs Intek 6hp. Summit racing did a lot with them in the early 2000s. One thing they did that got large gains was to reverse flow the head. Never tried it, I got the power I wanted (nearly 20hp on methanol) in the normal flow. The Preddy is very similar to the Intek, I imagine thats where it was derived from. We also removed all the intake guide from the port with no issues.

 

[DieselTech]

I used to run a pretty hot Briggs Intek 6hp. Summit racing did a lot with them in the early 2000s. One thing they did that got large gains was to reverse flow the head. Never tried it, I got the power I wanted (nearly 20hp on methanol) in the normal flow. The Preddy is very similar to the Intek, I imagine thats where it was derived from. We also removed all the intake guide from the port with no issues.

I never got into the OHV engines, this is my 1st one, that's why I've been doing alot of reading. This head ended up with .049" removed/decked with a 15.4cc combustion chamber. I might of got greedy with the router. With a .020" longer connecting rod, flattop piston & 15.4cc head it's going to have compression. Lmao it should make the power.
Wonder if the reverse flow is like a bias intake port design. I love my flathead briggs, but these engines opened up alot of fun/empty wallet syndrome for me. Soo much you can do with them. Got bored & added some cooling surface area.

 

[Cannonball3]

Nice work! The ohv engines are fun to mod! They were just showing up when I was into kart racing. It amazed us at the time just how easy(if you have $$) power was to get. Still the most formidable thing we faced were the open class
Blockzillas, especially ones running modded blocks using 4” Chevy pistons. When they showed up you either ran and hoped some one took em out or put you kart on the trailer and waited til next week when they likely weren't there. Saved wear and tear on your kart for no reason. We ran any way, no need to get all hyped up for nothing!

 

[DieselTech]

Nice work! The ohv engines are fun to mod! They were just showing up when I was into kart racing. It amazed us at the time just how easy(if you have $$) power was to get. Still the most formidable thing we faced were the open class
Blockzillas, especially ones running modded blocks using 4” Chevy pistons. When they showed up you either ran and hoped some one took em out or put you kart on the trailer and waited til next week when they likely weren't there. Saved wear and tear on your kart for no reason. We ran any way, no need to get all hyped up for nothing!

I got lazy by the time I was done, it looks ok! These predator heads are kinda goofy in their metallurgy, they are harder than all get out in spots & soft in others. Must be in the heat treatment.

 

[Nickt919]

Sometimes the work and fabrication can be as satisfying as riding them….at least for a true gear head.
I sure do like putting an engine together..especially when it’s not just plug n play.

 

[DieselTech]

Sometimes the work and fabrication can be as satisfying as riding them….at least for a true gear head.
I sure do like putting an engine together..especially when it’s not just plug n play.

Yeah I'm unsure how I'm even going to build it. Hp spec wise. Its definitely going to be a mutt of different engine parts.

 

[Chainlube]

Yeah I'm unsure how I'm even going to build it. Hp spec wise. Its definitely going to be a mutt of different engine parts.

As a cart engine, you can go nuts, everything is in the back. If she blows, it's all behind you and just a wee bit embarrassing, nothin' hurt.
On a bike you have to be a little more conservative.