Trip
Well-Known Member
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- 2,682
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- Ypsilanti Michigan U.S.
I bought a Walbro 813 from the local hobby shop the other day for $49.99 and I decided to give it a review.
If this is your first time hearing about or seeing an 813 you may be asking hey, there's no choke arm on that carb. Well that's right, it doesn't have one because it doesn't need one. It has an accelerator pump inside the carb body that shoots fuel into the intake for an extra boost in performance. It's supposed to help with the low end bog that the stock 668 cab has. Now you may ask, well then how do you start it without a choke? Instead of choking the carb on start-up, you just hit the throttle on your controller and it squirts in some fuel for easy start-up. Dual function. Cool huh?
This carburetor is considered as an upgrade for more performance. Does it live up to the hype? Read on and find out.
I installed this on a HobbyPro Mutilator 6 with a CY (Chung Yeng) 23cc with an X-can twin stinger.
Here is a tutorial of the install procedure. https://www.largescaleforums.com/showthread.php?t=11080 The install is the same as any other carb.
A few days ago I plugged the choke hole up with clear marine-grade silicone. I forgot to show that in the tutorial, but I can explain it later if need be.
All installed and ready for the first start-up, here we go...
First impression.
Start-up is easier now. It starts on the first pull instead of the third like it did with the previous carb. You do have to pump the gas to squirt some fuel into the intake though.
Prime, pump and pull, Voila it's running.
Once it fired up it was a little sluggish, so I ran the car around to warm it up. After all it was 15 degrees F outside. Once it was warmed up I did my foolproof method of carb tuning:
I stuck my boot under the back-end to get the tires off the ground and rapped her up to full throttle, it was a little rich on the high end so I turned in the needle until it was just a screamin'. Once it hit maximum rpm and didn't increase, I backed out the H.S needle about an 1/8 and called it good. Mid was strong and very responsive. I turned in the L.S needle to get a nice snappy takeoff and adjusted the throttle stop screw for a nice smooth idle. That's all I did to tune it, it took about 20 seconds for a nice smooth tune. That's it, nothing special.
I don't know why it took me so long to decide to make the change, I guess I was worried about a tuning nightmare, but boy was I wrong! This 813 really woke up this 23.
Some people say these carbs are made for the larger 28-31cc motors and others say the 813 is for the 23-26cc motors, but I can tell you from this experience, this little 23 rips better than it ever did with the stock (668) carb. The low end was almost breathtaking considering what little I did to achieve the result. I've never seen this buggy pull the front wheels in the grass before, now it does it quite often as long as it isn't spinning and destroying my lawn.
I know there a lot of people out there that say the 813 carbs are impossible to tune. I can say, tuning this was simple. If you can tune the stock 668 you can tune the 813. If you find tuning the 668 is a pain, well you may not be ready for the 813. Though, if you follow the aforementioned tuning method, any carb is a breeze to tune. I don't tune by temperature or plug color, I tune by ear. So please don't ask me what my needles are set at because it doesn't matter. No two motors are the same and no two carbs are the same, so therefore my needle settings will not be the same for you, plus there is ambient temperature, humidity, barometric pressure, etc... These all make a difference in tuning.
In conclusion:
I give it a 9.5 out of a 10, why not a 10? Well nothing is ever perfect, but this was the about the best 50 bucks I have spent on this buggy.
What do you think?
Trip..
If this is your first time hearing about or seeing an 813 you may be asking hey, there's no choke arm on that carb. Well that's right, it doesn't have one because it doesn't need one. It has an accelerator pump inside the carb body that shoots fuel into the intake for an extra boost in performance. It's supposed to help with the low end bog that the stock 668 cab has. Now you may ask, well then how do you start it without a choke? Instead of choking the carb on start-up, you just hit the throttle on your controller and it squirts in some fuel for easy start-up. Dual function. Cool huh?
This carburetor is considered as an upgrade for more performance. Does it live up to the hype? Read on and find out.
I installed this on a HobbyPro Mutilator 6 with a CY (Chung Yeng) 23cc with an X-can twin stinger.
Here is a tutorial of the install procedure. https://www.largescaleforums.com/showthread.php?t=11080 The install is the same as any other carb.
A few days ago I plugged the choke hole up with clear marine-grade silicone. I forgot to show that in the tutorial, but I can explain it later if need be.
All installed and ready for the first start-up, here we go...
First impression.
Start-up is easier now. It starts on the first pull instead of the third like it did with the previous carb. You do have to pump the gas to squirt some fuel into the intake though.
Prime, pump and pull, Voila it's running.
Once it fired up it was a little sluggish, so I ran the car around to warm it up. After all it was 15 degrees F outside. Once it was warmed up I did my foolproof method of carb tuning:
I stuck my boot under the back-end to get the tires off the ground and rapped her up to full throttle, it was a little rich on the high end so I turned in the needle until it was just a screamin'. Once it hit maximum rpm and didn't increase, I backed out the H.S needle about an 1/8 and called it good. Mid was strong and very responsive. I turned in the L.S needle to get a nice snappy takeoff and adjusted the throttle stop screw for a nice smooth idle. That's all I did to tune it, it took about 20 seconds for a nice smooth tune. That's it, nothing special.
I don't know why it took me so long to decide to make the change, I guess I was worried about a tuning nightmare, but boy was I wrong! This 813 really woke up this 23.
Some people say these carbs are made for the larger 28-31cc motors and others say the 813 is for the 23-26cc motors, but I can tell you from this experience, this little 23 rips better than it ever did with the stock (668) carb. The low end was almost breathtaking considering what little I did to achieve the result. I've never seen this buggy pull the front wheels in the grass before, now it does it quite often as long as it isn't spinning and destroying my lawn.
I know there a lot of people out there that say the 813 carbs are impossible to tune. I can say, tuning this was simple. If you can tune the stock 668 you can tune the 813. If you find tuning the 668 is a pain, well you may not be ready for the 813. Though, if you follow the aforementioned tuning method, any carb is a breeze to tune. I don't tune by temperature or plug color, I tune by ear. So please don't ask me what my needles are set at because it doesn't matter. No two motors are the same and no two carbs are the same, so therefore my needle settings will not be the same for you, plus there is ambient temperature, humidity, barometric pressure, etc... These all make a difference in tuning.
In conclusion:
I give it a 9.5 out of a 10, why not a 10? Well nothing is ever perfect, but this was the about the best 50 bucks I have spent on this buggy.
What do you think?
Trip..
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