Hey guys. I was sponsored an unrestricted motor for my son to run purple plate with. But I never thought about the carb needing re jetted for his class. I’m wondering what the correct jet would be? Also are adult unrestricted motors built differently than a plated motor? The track we was just at the other karts motors sounded more up in the power than ours did and we were on the same gearing.
Purple plate question
- Thread starter Dj09racer
- Start date
Yes it was, it was his back up unrestricted motor, I haven’t checked to see if the jetting was correct or not, but I’m assuming it was never changed, just because the other karts were against just sound like they are working more, with the same gearing. I wanted to check and know what I was talking about before I asked him I guess.
Where can you find these jets at, I’ve looked but can’t seem to find anything
Colt sr
Member
Turk brothers has what you want. Look at the plates first to verify which jet you want( they have recommended jet for each plate) then go to the part where the jets are and put your jet/jets in your cart.
1fasttiller
Member
Its Waaay more than just a jet change to go from unrestricted to purple plate or vice versa... cam, timing, carb are just a few things that a reputable builder will change. Maybe OK if you just want seat time and to play on Saturday nights but don't expect to be competitive.
That’s what I’ve been hearing, I never knew there was that much of a difference in the until I called another engine builder. He is def getting killed on the power side it seems like
He’s a local guy in my home town, it’s a holy Moses carb, he assured me it was set up correctly though
Colt sr
Member
If it is a holy Moses carb you could contact dover and double check. He is the builder/distributor of the holy Moses carbs
Gotcha thank you I appreciate it!
Thank you, I appreciate All the help
Tucker 357
Member
why do you go with a smaller jet with a bigger plate?
I like the chart shown by flattop1 for the main jet. But I'm always searching for a starting chart for the pilot jet. Don't know if there is such a chart that shows size for each plate that includes starting points for main, pilot w or w/o o-ring, etube, air mixture screw and any other starting data. Example: Red plate, etube = 0.042", main jet = 0.040", pilot jet w/o-ring = 0.035", pilot jet w/o o-ring = 0.028, screw = 1.5 turns out. Maybe there's too many variables too consider. I'm afraid that experimenting without a basic start may lean out the fuel system which is not a healthy situation.
The thing to remember is that the pilot jet supplies the fuel necessary to allow the engine to transition to the main jet.
If the engine bogs when the throttle is quickly opened, the pilot jet is too small.
Too large may cause idle flooding issues.
Not the end of the world, but can be problematic.
Always set this first. Then work on main jetting.
So, if you can get off idle without bogging, you are good to go.
Tuning is about getting the basics first.
If the engine bogs when the throttle is quickly opened, the pilot jet is too small.
Too large may cause idle flooding issues.
Not the end of the world, but can be problematic.
Always set this first. Then work on main jetting.
So, if you can get off idle without bogging, you are good to go.
Tuning is about getting the basics first.
OVALTECH1
Site Supporter
The plate causes a disturbance in the intake messing with the carb signal which hinders the engines ability to draw the correct amount of fuel/air on its intake stroke. That causes a lean condition that hinders performance which you try and help counteract with a bigger jet. ( best hillbilly breakdown I got, I’m sure I missed something)