ltd mod to open

spincycle

spincycle

Member
been running a ltd mod animal with stock valves with dual springs, stock lifters, good cam, flathead stroker crank, billet rod and .140 over piston on alcohol with a tillotson HL-304WX carb...got a head with good port work done to pit and big valves to put on the motor...question is, will that HL-304WX carb be enough to feed it and keep it happy? if not, what carb might be a better fit for that combo? Thx!
 
You already know the carb . The rule of thumb is same size as intake valve .
Any idea what the head flows in crm ? Big valves and port work should be an improvement with the current carb .
 
My first concern would be that big piston and that long rod. What have you done to the crankshaft as far as extra counter weighting?

I'd get with someone who is familiar with all that stuff you're adding and see what they say. You very definitely are throwing the engine way way out of balance.
 
The 304WX carb works great with a true "limited modified" animal. That is far from what you are running.
You are already under-carb'd in my opinion for your build.
You can't just go swapping parts out and hope for the best -- that's a good way to kill an engine.


-----
🏁Thanks and God bless,
Brian Carlson
Carlson Racing Engines
Vector Cutz
www.CarlsonMotorsports.com
Carlson Motorsports on Facebook
31 years of service to the karting industry
Linden, IN
765-339-4407
bcarlson@CarlsonMotorsports.com
 
CarlsonMotorsports said:
The 304WX carb works great with a true "limited modified" animal. That is far from what you are running.
You are already under-carb'd in my opinion for your build.
You can't just go swapping parts out and hope for the best -- that's a good way to kill an engine.


-----
🏁Thanks and God bless,
Brian Carlson
Carlson Racing Engines
Vector Cutz
www.CarlsonMotorsports.com
Carlson Motorsports on Facebook
31 years of service to the karting industry
Linden, IN
765-339-4407
bcarlson@CarlsonMotorsports.com
[/QUOTE
Throw me a bone here, what carb might you recommend? Disclaimer....I'm not a knowledgeable motor guy....🤭
Click to expand...
 
Last edited:
I don't know what you're head flows currently, or even what cam and lift you are using, but I would start with a 28 Mikuni slide is my thinking. If you really like Tilly's you could look at an HR carb - 181, or 191 (same carb w./ bigger bore.) You may be able to use something bigger, but there's no way to tell with out knowing what you've got to work with flow wise. For sure that 304 is choking it down tremendously.
 
CarlsonMotorsports said:
I don't know what you're head flows currently, or even what cam and lift you are using, but I would start with a 28 Mikuni slide is my thinking. If you really like Tilly's you could look at an HR carb - 181, or 191 (same carb w./ bigger bore.) You may be able to use something bigger, but there's no way to tell with out knowing what you've got to work with flow wise. For sure that 304 is choking it down tremendously.
Click to expand...
I build kart engines "in my garage" so to speak, with stuff I can't say I know the exact tech specs on every piece...it's nothing more than a true hobby to me, i just try to learn as much as I can along the way and maybe, just maybe, I'll hit a good combination... certainly not the best way to attack things, but only have xxxxx number of dollars to play with at any given time....thx for your help! 🙂
 
Not a stupid question, rather I'm seeking education/knowledge....when talking carb sizes, and a carb is described as 28mm, 33mm, 34mm...etc, where in the carb is that measurement being taken? Thx!
 
Thanks everyone for the input, I got the much needed education on how to best proceed with this engine package project...yes, beforehand, the combination was a ways off and most likely would have not performed very well or up to its potential...with the correct intake/carb and a little more head porting attention, it should make one powerful little piece...😉
 
Last edited:
You must log in or register to reply here.
Back
Top