How Many RPM Can You Get Out Of 18lb Valve Springs On A Predator 212? How to change valve springs

Swapping from factory valve springs to 18lb valve springs on Harbor freight hemi Predator 212. How many rpms can be gained? Governor has been removed.

[@fatbuddycat]

The best part is how reassuring your accent is. You've obviously worked for or on at least 5, maybe 6 Nascar.....🙄. Great video, thanks!

[@morgz1055]

125 bucks for that frame?! What the hell

[@tonymayhew191]

You said to set the piston to top dead center, but you didn't tell your viewers that you are supposed to turn the engine 180 degrees out on the firing stroke to set the valve lashes and not the other side of the cam.

[@db3170]

Dog needs springs too

[@asphaltcowboy7868]

Speed equals gear ratio...if you would run a smaller rear sprocket, you will pick up more top end..

[@jwsbackyard6413]

Yeah as I mentioned in the video I had played around with multiple sprocket sizes and had found a good medium between no low end torque and too much torque but just needed a little more speed up top without changing the gear ratio. The extra rpms solved the problem.

[@bainmccartney685]

I run an 19 tooth 35 chain clutch and 60 tooth 35 chain rear and the fastest I've hit was 65mph.

[@prebaned]

Whe you get that header?

[@jwsbackyard6413]

eBay many years ago

[@rolandojuarez1641]

Very helpful.. thanks

[@witosarlaw]

Mantap bang

[@bigdaddywillerson6905]

😮 did he just take that spark plug out with a drill I'm really hoping you don't put it back in with a drill I'm going to continue watching😊

[@jwsbackyard6413]

Work smarter not harder ;)

[@chancewindham1718]

I highly recommend upgrading your carb if you want more speed.

[@jwsbackyard6413]

Upgrading the carb would definitely help with acceleration so it would get to its top speed faster but the top speed is limited by the gearing and the max engine rpm. To increase the top speed I would either have to adjust the gear ratio by either going with a smaller axle sprocket, increasing the number of teeth on the clutch or by increasing the engine rpm.

[@chancewindham1718]

@@jwsbackyard6413 You can certainly increase your top speed by upgrading the carb. The stock carb on these motors is not providing enough fuel for you to max out your gearing etc. Speaking from experience. Every build I've done with these motors, when I only replace the carb I gained top speed. I mean youre right about your speed being restricted by gear ratio etc, but not with this carb. Also have you though about installing a torque converter in place if the centri?

[@chancewindham1718]

@@jwsbackyard6413 I presume you are rockin the stock jets too? Those carbs are a major weak point in those motors right out of the box.

[@chancewindham1718]

@@jwsbackyard6413 you're also correct about the acceleration though. Massive difference in acceleration.

[@jwsbackyard6413]

I normally step up to a 32 jet with intake and exhaust. In this case the engine starts to float the valves which is what's limiting top speed so the gearing and rpm are the limiting factors not lack of power. This cart is one wheel drive so I've had to limit torque to keep it from continuously loosing traction and trying to bring the rear end around which is why I've stuck with the centrifugal as opposed to going with a torque converter. I'm using torque converters on two of my live axle setups though.

[@xxzeroxgamerxx-6735]

Noted

[@luskavarna]

Timing advance with #6 keway.

[@A.E.Lanman777]

2:21 that bolt right there snapped off on me. Is it a big deal?

[@jwsbackyard6413]

It will probably leak oil. Not the end of the world but it get the broken one out and put another bolt in

[@Gazanova85]

the funny thing is I get over 6000rpm with the 18lb springs on stock motor

[@PewPewGuy85]

How?

[@Gazanova85]

@PewPewGuy85 have it geared right and also remove the governor

[@alternatemusicaddict5226]

Need a cam and 40$ pvl flywheel

[@GabrielMiniBikR]

Is the governor removal all you did? do you need anything else before the springs for safety?

[@jwsbackyard6413]

Yes, just a governor removal. Most suggest a billet flywheel with the governor removal and upgraded springs. The factory flywheel usually holds up fine with factory springs because valve float limits rpm’s but with upgraded springs there is a higher chance of the factory cast flywheel coming apart.

[@hectorjimenez7115]

😊

[@PAiN46k]

Would you know the valve lash for 212cc non hemi with 18lb Springs?

[@jwsbackyard6413]

I usually just set intake and exhaust to .003. ARC has a pretty in depth video on setting valve lash where they suggest differently that you might want to check out.

[@jwsbackyard6413]

Here's their video. m.kzbin.info/www/bejne/f4S4XmZsYp6Ygtk

[@steveoh625]

.003 on intake .004 on exhaust.

[@rechargegamesstudio2803]

Neat x2

[@ulyssescontreras4360]

Put a torque converter

[@jwsbackyard6413]

It’s a one where drive kart and just spins or pulls to one side with the slightest bit of torque. I have torque converters on my other karts but it just wasn’t right for this kart until I swapped to a live axle.

[@exiled3503]

Sounds lean

[@steveoh625]

go smaller sprocket on the rear axel.

[@jwsbackyard6413]

At the time the kart was one wheel drive and I was having trouble finding affordable sprockets and a gear ratio that wasn’t either so aggressive that it pulled to one side from too much torque or so conservative that it would struggle to get moving. I’ve converted but to a live axle since then and have a quick change sprocket on the axle so I’ve been able to change up the gearing at the axle.

[@dullah5.0]

does it give top speed?

[@jwsbackyard6413]

It allowed for higher rpm before floating the valves so it did give me a little bit of extra speed. It did lug the engine down though and I could feel a noticeable decrease in power from the extra resistance inside the engine. So a decrease in power and acceleration but increase in top speed.

[@steveoh625]

im guessing 30mph

[@logancarpenter2910]

How fast can your dog go

[@jwsbackyard6413]

It’s the neighbors dog but I’ve got it wide open and it hangs with me for a while so I’d say at least 35mph. It’s a fast dog.

[@damnthiccassboye7138]

@@jwsbackyard6413probably drunk 10gallons of nitromethane when he was 2 weeks old

[@jwsbackyard6413]

Haha

[@daneulekowski929]

any idea what rpm can be safely turned with the stock flywheel. Wondering if I can pull the govenor and do 18 lb springs carb jet and a pipe, with the stock flywheel. Great video by the way, just picked up a 212 for $99 at Harbor Freight

[@jwsbackyard6413]

Honestly I don't know it's real limitation and if you look at forums most are hyperbolic and say you need a new fly wheel even with the governor removed. What I can tell you is that I have 5 predators all with factory flywheels and haven't had any problems for years. One has 22lb springs, intake, exhaust and cam and has held up fine. The cart in this video has the 18lb springs, intake and exhaust and head port and has held up fine. The others are using stock springs and have Intake and exhaust plus Nitrous on one.

[@daneulekowski929]

@@jwsbackyard6413 wow, great info. I'm only looking for around 5500 rpm tops for a cart I used to run a Animal on, don't want to drop a grand on another one.

[@jwsbackyard6413]

Yeah that's a lot for a go kart engine when you can get a pretty reliable one with aftermarket support for $99.

[@GibbSaw63]

@@jwsbackyard6413 Yeah the people posting on those forums are so worried about something I've never seen or heard of happening

[@Deucealive75]

Billet and other after market flywheels are better from a performance perspective. Takes more power to spin a 5 1/2 pound stock flywheel than it takes to spin a 3 1/2 pound flywheel. Who builds an engine and uses the stock flywheel? lol. Same thing with the 18 lb springs. If I'm floating valves at 5200 RPM I would replace the stock springs with stock springs to get 5500 if that was the target max RPM. If valve float at 5200 is normal for a Predator then that sucks. Valve float on my 196's is around the 5800-5900 range. I don't think I would use 18 lb springs for anything because the better big power cams use 22 lb+ springs. And there are cams that support 6500 plus RPM with stock springs. 18 lb springs rob power in the stock spring RPM range on mainly stock engines.