Trying to build a 20+ hp predator 212

[butterbagz]

I wasn't sure if could get 20+ hp with this idea but, using ported and polished hemi head, stage 4 kit, 356 lift cam with 36 lb valve springs.

 

[BaconBitRacing]

It's certainly possible to do, with those things I do not know, but why not a 420cc predator?

 

[butterbagz]

It's certainly possible to do, with those things I do not know, but why not a 420cc predator?

I bought a used go kart for 150

 

[butterbagz]

It's certainly possible to do, with those things I do not know, but why not a 420cc predator?

Also I need something lightweight

 

[butterbagz]

Since I'm 15 and put my go kart into my grandpa's suv

 

[ezcome-ezgo]

If it was me, I would work up to a 10hp output first, then see if I was still greedy enough to proceed.

 

[butterbagz]

If it was me, I would work up to a 10hp output first, then see if I was still greedy enough to proceed.

I'm just put high performance parts in it and watch a tutorial

 

[Denny]

420 is not that much heavier but has gobs more torque than any 212 could ever dream of! Torque is what makes a cart move!

 

[ezcome-ezgo]

Watch a video, throw money at it. Hope it works out.

 

[Master Hack]

Watch a video, throw money at it. Hope it works out.

Come awnn! Mr. Negative! Everyone knows that youtube has only highly educational, accurate information! Fact Is who needs Skool? Wanna learn to do something the right way? Youtube! it always works out! Sadly there was no Youtube back when I was a kid. We saw dinosaurs roaming almost everyday tho!

 

[panchothedog]

Hey young fella. With a hemi head and a .356" lift cam your valves are going to hit the piston long before the cam reaches full lift. Getting 20 hp will be very expensive. Getting 15 to 16 is quite doable. If you already have a hemi engine, then buy a bare non hemi head to build. If you don't have the engine yet, then buy
the non hemi. The non hemi head will bolt on your engine. Port the head, also mill it .065" to raise compression. You need a flat top piston ( hemi comes with one, ) non hemi you need to buy an after market one. Any cam with more than .310" lift you need extra long valves to prevent coil bind. And with 36 lb valve springs you need stainless steel valves, otherwise you stand a good chance of ripping the heads right off the pot metal stock ones. 26lb springs and a lower lift cam will get the job done. You have been watching too many vroom vroom videos. Educate yourself a little by watching Red Beards Garage. He will show you close up how to build your engine. Then watch his series of videos titled the road to horsepower. He installs speed parts on a predator engine, and after each part runs the engine on a dyno. Letting you know how much power each modification is worth. Value to you is priceless.

 

[butterbagz]

I've been watching road to horse power red beard garage is kinda how I found out about the stage 4 kit

 

[butterbagz]

Thanks for the info I kinda needed the parts so your saying if I get a 356 I need stainless steel valves and extra long ones correct? I'm waiting for red beards ep 8 for road to horsepower. That one will specifically deal with a .356 cam

 

[bob58o]

I wouldn’t buy a kit. You can usually get better parts cheaper elsewhere. For instance, what carb does the kit use?

 

[butterbagz]

I wouldn’t buy a kit. You can usually get better parts cheaper elsewhere. For instance, what carb does the kit use?

I'm not going to get a kit I was just gonna get the parts separately

 

[butterbagz]

But I'm getting a 28mm carb

 

[butterbagz]

Hey young fella. With a hemi head and a .356" lift cam your valves are going to hit the piston long before the cam reaches full lift. Getting 20 hp will be very expensive. Getting 15 to 16 is quite doable. If you already have a hemi engine, then buy a bare non hemi head to build. If you don't have the engine yet, then buy
the non hemi. The non hemi head will bolt on your engine. Port the head, also mill it .065" to raise compression. You need a flat top piston ( hemi comes with one, ) non hemi you need to buy an after market one. Any cam with more than .310" lift you need extra long valves to prevent coil bind. And with 36 lb valve springs you need stainless steel valves, otherwise you stand a good chance of ripping the heads right off the pot metal stock ones. 26lb springs and a lower lift cam will get the job done. You have been watching too many vroom vroom videos. Educate yourself a little by watching Red Beards Garage. He will show you close up how to build your engine. Then watch his series of videos titled the road to horsepower. He installs speed parts on a predator engine, and after each part runs the engine on a dyno. Letting you know how much power each modification is worth. Value to you is priceless.

What If I get a 32/28 big block valve hemi?

 

[Denny]

Buy a 420! Only get a hemi if that’s all they have! Wedge head will make more power!

 

[panchothedog]

butterbagz. You have clearly fallen for the big numbers buz words without really understanding what's going on. I am not trying to be mean, or put you down. I want to try to educate you a little bit. In fact I am glad that at only 15 years old you want to build an engine. Hemi sounds cool and all that, but for the Predator engine that is not the one to modify. The reason is because the valves sit on a angle. So when the valve opens ( lifted by the cam ) the lower edge of the valve is
much closer to the piston. With the non hemi head, the valves sit straight up and down. The whole face of the valve comes down evenly. You can use a cam with much more lift SAFELY with the conventional or wedge head. Most ALL big valve heads or modified heads ( high compression ) are the non hemi style for the reason explained above. Valve to piston clearance. Heads with 32mm intake valves are very expensive, not to mention that the larger valves have a history of burning and melting the seat. A 28 mm carburetor could be used on a very heavily modified engine like in a jr. Dragster, but for a go kart ( even with a highly built engine ) it is way too much. A properly jetted 24mm Makuni flat slide will feed a very built engine. Tone it down a little and build your first one.

 

[BrownStainRacing]

@butterbagz
Pancho, speaks the truth. Listen and pay attention.
Start small and work your way up.

Mark, from EC Carbs put together some nice "builds for beginners" that won't break the bank.

Jus looking at the parts combo of each build, I'm sure they will have plenty of power, IF the compression ratio and ignition timing is right.

As his builds get into bigger cams, he gets away from the hemi head. There's a reason for that, jus like Pancho is saying.

Have a look for yourself.
Good luck with your build, .

EC's 2023 Small Engine Builders Guide