Image of Reverse Flow Chevy: http://67-72chevytrucks.com/vboard/showthread.php?t=188402
In this video we take a run of the mill Predator 212 and see if we can get it to run backwards! We’ve always wanted to experiment and see if it could be done. Not sure of the applications for such an engine but if anyone ends up getting one to work and uses it let us know! What we did to get it to run was flip the coil, bolt the exhaust to the intake, and modify an exhaust into an intake that accepts a Mikuni carburetor from Gopowersports. You can be the judge of how well it works, links to the parts we used in the description below!
Thank y’all for watching, stay safe, and be sure to stay tuned for the next video!
MERCH
MERCHANDISE CUSTOM DESIGNED BY YOURS TRULY
https://teespring.com/stores/build-break-repeat
TOOLS
RogueFab Tubing Notcher
https://www.roguefab.com/product/versanotcher-universal-tubing-notcher/
Pro-tools Tubing Bender
https://pro-tools.com/collections/tube-and-pipe-benders
Optrel Crystal 2.0 Welding Mask
https://usa.optrel.com/en/eye_protection_helmets/products/show/crystal20/
Optrel Grinding Mask
https://usa.optrel.com/en/products/augenschutz/helme-zum-schleifen-schneiden/products/show/clearmaxx/
MUSIC
Music - Background and Montage Music Is From Endemic Sounds
https://www.epidemicsound.com/
Intro Song - Jimmi by Andrew Applepie
https://www.youtube.com/watch?v=l1zHz8pYfyQ&ab_channel=AndrewApplepie
—————PARTS—————
RHB31 VZ21 Turbo – Amazon Affiliate link: https://amzn.to/3mMWAAu
F&B Header - https://www.gopowersports.com/header-pipe-f-b-small-block-low-center-exit/?utm_source=YOUTUBE&utm_campaign=Build_Break_Repeat&utm_medium=Video
Performance Header - https://www.gopowersports.com/header-pipe-predator-performance-staged/?utm_source=YOUTUBE&utm_campaign=Build_Break_Repeat&utm_medium=Video
22MM Mikuni Carb Performance Kit - https://www.gopowersports.com/22mm-mikuni-carburetor-performance-kit/?utm_source=YOUTUBE&utm_campaign=Build_Break_Repeat&utm_medium=Video
Predator 212 - https://www.gopowersports.com/6-5-hp-212cc-predator-engine/?utm_source=YOUTUBE&utm_campaign=Build_Break_Repeat&utm_medium=Video
Weld On Tabs - Amazon affiliate link: https://amzn.to/2XOoIIv
In this video we take a run of the mill Predator 212 and see if we can get it to run backwards! We’ve always wanted to experiment and see if it could be done. Not sure of the applications for such an engine but if anyone ends up getting one to work and uses it let us know! What we did to get it to run was flip the coil, bolt the exhaust to the intake, and modify an exhaust into an intake that accepts a Mikuni carburetor from Gopowersports. You can be the judge of how well it works, links to the parts we used in the description below!
Thank y’all for watching, stay safe, and be sure to stay tuned for the next video!
MERCH
MERCHANDISE CUSTOM DESIGNED BY YOURS TRULY
https://teespring.com/stores/build-break-repeat
TOOLS
RogueFab Tubing Notcher
https://www.roguefab.com/product/versanotcher-universal-tubing-notcher/
Pro-tools Tubing Bender
https://pro-tools.com/collections/tube-and-pipe-benders
Optrel Crystal 2.0 Welding Mask
https://usa.optrel.com/en/eye_protection_helmets/products/show/crystal20/
Optrel Grinding Mask
https://usa.optrel.com/en/products/augenschutz/helme-zum-schleifen-schneiden/products/show/clearmaxx/
MUSIC
Music - Background and Montage Music Is From Endemic Sounds
https://www.epidemicsound.com/
Intro Song - Jimmi by Andrew Applepie
https://www.youtube.com/watch?v=l1zHz8pYfyQ&ab_channel=AndrewApplepie
—————PARTS—————
RHB31 VZ21 Turbo – Amazon Affiliate link: https://amzn.to/3mMWAAu
F&B Header - https://www.gopowersports.com/header-pipe-f-b-small-block-low-center-exit/?utm_source=YOUTUBE&utm_campaign=Build_Break_Repeat&utm_medium=Video
Performance Header - https://www.gopowersports.com/header-pipe-predator-performance-staged/?utm_source=YOUTUBE&utm_campaign=Build_Break_Repeat&utm_medium=Video
22MM Mikuni Carb Performance Kit - https://www.gopowersports.com/22mm-mikuni-carburetor-performance-kit/?utm_source=YOUTUBE&utm_campaign=Build_Break_Repeat&utm_medium=Video
Predator 212 - https://www.gopowersports.com/6-5-hp-212cc-predator-engine/?utm_source=YOUTUBE&utm_campaign=Build_Break_Repeat&utm_medium=Video
Weld On Tabs - Amazon affiliate link: https://amzn.to/2XOoIIv
Oh all right so here we have a run-of-the-mill predator 212. she's, pretty basic right out of the box. It's actually been sitting in storage a little bit, but i remember seeing a picture on instagram of someone who took like a chevy 350 and put carburetors on every single exhaust runner and then made the intake, the exhaust, and ever since i saw that thing. We've been wanting to try to do that on a predator um, so i'm sure you're pretty intrigued by this thumbnail.
I don't know if this vid is going to get a lot of views, it's kind of just stupid but like it's something. I've wanted to do and we've just like been thinking about and we're kind of out of content for the time being waiting on some parts. So we're going to do it, but before we can start getting the carburetor just bolted onto the exhaust, i want to go over to the drawing board and figure out the things we need to prove before we waste a bunch of time. So we're going to apply a little bit of a scientific method.
To this thing, the first thing we need to check for is if this thing makes vacuum through the exhaust, when it's cranked over in the reverse direction. So that's kind of the first step. If it doesn't draw in anything because of the cam or, however, that works, then we're out of luck. The next thing we're going to check for is we're going to take off the spark plug crank it over see.
If we have spark, then, after that, before we start doing the fabrication with our carburetor and stuff, like that, we'll just use starter fluid. And then, after that, we'll do the fab to get the carb up, make a cool exhaust and see if it runs backwards. And then, when it's running backwards, it's actually quite interesting because, like the things like the cam gears and stuff are actually going to be going in the opposite direction than they were engineered to turn kind of like. If you were um towing, something in reverse.
I'm kind of how the differential gears don't quite line up the right way, so it might just blow up, but we're here for that that'd be pretty fun all right. So first thing we got ta do is just pull everything off. We do not need this top plate and we also don't need the carb over there. Obviously so good stuff, all right, that's actually pretty good.
Oh yep, it's got vacuum. It makes good vacuum good running backwards. I'm actually pretty curious, like i think it has a chance. I i don't know man.
This is so weird yeah all right wow, i don't think that's ever come out. Actually so check number one off the list. Now we ought to pull the spark plug and see if it's gon na work. I i guess maybe my only concern is if like when it's running over backwards, the magneto might not work in the same way.
There i mean it should be a pretty easy test right, all right, so there's a little spark there. Oh man, we might be out of luck right now, step one roll, the switcheroo flipping the coil. This is kind of dumb guys. It's gon na reach too yeah she's gon na rip for about 30 seconds. Maybe i actually don't know if this is gon na work. It kind of makes sense, though i don't know we're just doing this for fun. I really enjoy kind of troubleshooting randomly with this sort of stuff all right, kiddos moment of it truth bro. This is stupid.
Oh it just flipped over that's good there. Let's see is this gon na reach? Let's see, let's see, okay! Well, that's right where exhaust is coming out so for testing it'll be all right. So now we're gon na do is we're gon na shoot a dab of starter fluid in there and see what happens all right moment of truth, my dear friends, let's uh cross our fingers. I think it's gon na work like i'm actually pretty confident hold up.
We have a little stand thing that we can bolt it to it's, probably a good idea, because i only have so many hands, so it just has some bolts on there, so it slides on this should hopefully keep it from running away. All right go crank. It down and then we'll let it rip nothing. I'm actually kind of scared.
I think it'll be okay, though ready yep, okay, ready. It's gon na run, dude yeah, okay, okay, that wasn't smart. How is it on fire but still running? Well, the good news is: it ran a little bit the bad news. Is it detonated and caught on fire um.
So do you think we should put a carb on it or do you want to keep trying this? I mean, i think it. It seemed like we kind of like got one good ignition and then wasn't running right, and maybe that's why i think we should try again starter fluid. Like i don't know, it seemed like we got like one good fire and then, after that, everything was just like burning out the intake. Okay, so we can see maybe hold on the starter for the next time, if it uh dies, yeah or catches on fire, but face shields were a good idea.
Okay, so, instead of like spraying the starter fluid. Oh, you know what i bet. What happened is the starter. Fluid was probably in the same range as the exhaust, so what happened is i bet it sparked from over here.
Oh right, maybe that's that's very likely so anyways to avoid that we're just gon na put this go powersports, fmv header, pipe on there link in the description and we'll be able to inject starter fluid into here. Good, okay, okay, it's not that sketch yeah! It sounds like it exhausted, like it sounded like a normal go-kart exhaust like it shot flying back. Oh really, let's try. It again go ready, okay, ready, yep dude! I could have sworn yeah it exhausted out of here like that, did not sound like it was going through there.
It sounded like a go-kart. How does it run like that? Then? Do you think our cam's off? Well, we can't really change it like it's okay, so it sounded like it. It pulls it in for like once and then it explodes it and then runs right, hey, let's we're going to review the footage and see if we have exhaust coming out of the intake. Okay, i'll do i don't know, that's kind of good. I feel a little bit better about this thing. Now, that's on the ground too. All right ready all right. Three three did it right.
Oh i mean it fired, ready what wow dude yeah. This looks. Super cool right now i mean i've, never seen a predator like this, but our new plan is so we're thinking that um, the the uh starter, fluid kind of showed us that, like having the carb all the way out here is not gon na, be a good Idea, because, when it backfires we're gon na have like all of this full, basically just a pipe bomb of gas, so we're gon na. Just we have this other header and we're gon na cut it like, as short as we can, to get it level and we'll have our carb like sitting up here pretty nice.
It looks cool though feast, your eyes, friends, it's about as good as it gets. I'm gon na bolt it up carbs gon na go under here. I actually don't know if this is clocked right, but yeah yeah, we're sorry about this whole video, okay, yeah, it's gon na work, dude. I think it's gon na work, yeah fired well out of there.
Yeah all right guys, cherry on top. That's beautiful right! Thank you! Go power, sports! All right! You ever seen a prettier predator. I don't think so all right fuel on yep she's, looking good guys. This is actually gon na be hilarious if it works, i'm i'm i've been wanting to like i've.
I've literally been talking about this for so long um, i'm probably annoying them, but we are about to do it we'll see yeah actually, um. I give it a 50 chance of working, i don't think it'd just blow up, like i mean that'd, be cool kind of it can it'll handle like backfires like it's not going to explode. Okay here goes nothing you ready yeah. Is it immediately stops them huh? That is weird, oh it's! So close, it's really weird! It's almost like! It's not meant to do this, damn we're so close though i mean we could try to macony.
That was a failure, so we're going to try to throw him akuni on it. At least all right, we're kind of low on the uh on the morale and stuff right now, but we're oh yeah, we're also just using the mikuni off the little rascal and we're literally using this throttle. It's really stupid. This is high effort.
It's kind of fun like we're just enjoying ourselves like it. I don't know you got to do something like not as legit every once in a while just to like kind of let some steam off. Maybe you guys don't have to do that, but i kind of have this sort of creative energy that i need to get rid of, or it kind of carry over to this stuff. Okay, all right! All right, let's go! Oh, we did it ready kind of all right.
Oh it's so close. All right, you're gon na sit over there. Can i just we're gon na see if we can run longer ready, oh dude, that was like no. Is that not trying to turn the choke off or it was off right? It's on right now: oh okay, ready, yep! Well also this car. This is shooting so many flames. Well yeah. This mikuni is meant for the little rascal, which has a 225 toilets and that's true. So it's definitely right all right ready all right yep, i mean she's, not happy, but she runs.
I know dude, it sounds it sounds. I don't know. I just wanted to do this. If you all know i i don't know how this video is gon na.
Do the comments will probably be atrocious um, but i've always wanted to try it so sorry ready yeah. Ah we got ta be very careful um, maybe i'll. Try and rev it up a bit and then turn up turn choke off all right. I say no choke and try to like get it to climb yeah all right started.
Well, we're done we're done we're done. That was horrifying. Oh, my god, dude that explodes oh wow, okay, yeah, we're calling it this is it's over. Let me do that.
Well, that's where we're gon na call it for a video we're calling it a day, um yeah. This started out as an idea, and here it is in front of me kind of just something that probably shouldn't have been done to begin with. But it was interesting to say the least, and it was really fun to just kind of try it and it did run um jason. We kind of pulled it off in a panic because it was just climbing and climbing and rpms and around like kind of like a runway diesel or something like that um.
So yeah this isn't feasible. I guess we were thinking that hey, maybe for some reason it might actually work if you run it backwards and kind of flip everything around, and then we can put it on a cart or something, and you know what maybe, if we kind of got the jetting Right and spent like a couple more days on this thing, then that could be the case, but that would require spending a couple more days on this and we just don't think that's really worth it. But if you're intrigued, you can try yourself and send us a video on instagram or something like that. We'd love to see it, but thank you guys for watching.
Thank you. Go powersports um, while we kind of deface some of their parts in this video they are from go powersports, so check them out. We'll put the links in the description. So thank you all for watching.
We'll see you next time. You.
your timing is probably way past top dead center and thats why it barely runs
This is perfect for a motorized bike. It would eliminate the need for a dangerous jack shaft. It will allow you to use the stock cog an derailleur. Just add a positron flywheel on the crank. A centrifugal clutch, A belt and a belt pulley to the positron flywheel.
1. I am concerned about the cam lobes. If the lobes are not symmetrical then the cam lobes and valves will wear out quick.
2. Reversing the magneto should not be necessary.
You didn't need to flip the coil over, it would have worked as it was.
i am thinking of doing that to a lifan 2v78f-3 cause the crankshaft's are on the flipped side.
rotate the magnet too. i will flip heads and pistons and adjust timing gear by 180°
The compression release is on the wrong valve now. So on the power stroke its opening the old exhaust valve a smidge when trying to start. So its blowing backward through the carb
Good try but valve timing is off its still trying to fire at the wrong time if it was a 2 stroke yeah it would work. Upen it up and move advance the valves with the timing cam
I learn how to fix my 2-stroke engine from running in reverse more on these comments than I do on googling it
My two stroke on my dirt bike runs very well in reverse I wish I knew how to fix it
Switch the intake and exhaust valve lash tolerances. I can’t remember off the top of my head what they are but you’d probably have better luck that way.
Noticed you're wrapping the string differently between starts. That means it is turning engine the wrong way sometimes..
I say 100 % success the intake was too long and the tilt of the carb was not letting the float work properly you could probly modify the pitch of your cam to close the valves at the right timing thats why you were getting a little backfire through the carb its supposed to be a gradual open then drops closed just smooth the drop side and drop the smooth side you can even add weld on top to make the valves open more all kinds of stuff i see small engine racers do it all the time how hard could it be lol good show dont let anyone tell you are stupid for doing the things you enjoy F the haters do your own thing youve already got this far who knows where it could take you.👍
Great vid but I have this problem with my predator 212 I put a mikuni on it and welded an exhaust for it but it only starts on choke and when it starts on choke the thing runs away like The engine revs itself out
This is just wrong. I feel like the Earth is rotating backwards now. 🙁
You guys are going to get 1 million views because I like you running it and hearing the your intro I can’t help it what song is that 1 million views from Disney rewinding video
Did you try reversing the adjustments on the valves. Swap intake lash with exhaust lash?
Tbh i didnt think that would actually work but damn u guys did it good job
Can you please tell me why are you scared of every think you do what can happen to you is a engine not fucking bomb i dont understand worst thing that could happend is socket flying but i is like 1 in a 1000 chance to hit you. Like engine started you run away like a fucking headles chiken
it would work no problem you just didnt adjust any timing and it was firing before tdc, hence the carb flames
I WANT TO SEE IT ON A GO KART
AND MAKE IT RUN AND ADJUSTING THE PORTS OR AIR AND EXHUAST
I don't remember seeing you guys time it so if you did ignore me. But the timing running in one direction won't be right to run it in the opposite direction
I had an old dirt bike where the stater had shifter the timing so far that when you would start it it would fire one then run in reverse. Very sketchy when your in the woods.
I think the Mikuni only works because it had more fuel the exhaust valve smaller then the intake valve so less gas is getting sucked in from the smaller exhaust valve instead of the intake valve like it should be I think that is the problem
It is firing the sparkplug after tdc instead of a few degrees before. Wont have good power
you will just have to reverse the valves lashes 0.004 intake. 0.006 exhaust. And don't have your throttle being stretched out i could see the 1/2 inch of bare cable.
That was awesome being you changed the distance from carb and the valves would be wrong size etc worked better then expected
You know its a good video when someone says "The face sheilds where a good idea!".
If I remember correctly, those engines do have a compression release built into the cam, on the exhaust side. Just a idea to help
This was an awesome idea!!!! I LOVE seeing engine experiments!!! I'm now subscribed!!!