Everyone does things differently, it does in fact increase performance but is not absolutely neccessary. On a stock carb and engine it makes a noticeable difference, runs much smoother through the RPM range and idles far better. I have tried it with and without over and over because I was curious. A modded carb on a HP engine you'd probably never know the difference, but my kart racing buddy leaves his in and he has forgottten more about briggs 5hp engines than most folks could eber hope to learn. He made a helix spacer for his son's JR dragster's Blockzilla and was protested, the sanctioning body said it was an unfair advantage. IMO it helps but I'm no expert, i just know many of them!:thumbsup:
I did exactly that with this motor so the air filter would fit in the bike.. I friggin hate those damn carburetors but love briggs motors.... I usually run Tecumseh carbs on mine, but at the time I was not sure how well the Tecumseh (bowl) carb would like being on the angled rupp frame.. So at the time I figured I'd throw this pulsejet on the bike and it should work fine... :shrug:
But I ran into an air cleaner clearence problem.. So I removed the choke, and just screwed a big ole washer over the top where the air cleaner would have been.. Then rammed a copper tube into the end and 1/2 of a sawed in half Tecumseh carb, to hook my tecumseh air filter to from there..
I figured not having to flow through that goofy ass square holes tipped up at a 90 would HAVE to make it run better too... (win win) But MAN it made a HELL of a difference... I was surprised... :smile:
nice bike restore kid, i like the walbros from 12.5hp briggs flatty's flow well and are not hard to make a manifold for. how do you keep the tec carbs going lol? does anyone know what the max is i ream the venturi on the *3, 4hp carb? no sanctioned body just all out. i like to fool people lol:thumbsup: