fbt551 Posted August 12, 2014 Report Share Posted August 12, 2014 What is the difference between pump and gravity carbs? Is there visual diffrence? Can they be run either way? Whay are the tuning advantages of either one? Quote Link to comment Share on other sites More sharing options...
m671054 Posted August 12, 2014 Report Share Posted August 12, 2014 Float needle and float arm bend is different on lectrons. If you change the parts you can run either way. Pumps are used when gravity wont keep up. Quote Link to comment Share on other sites More sharing options...
RadarRacing Posted August 12, 2014 Report Share Posted August 12, 2014 Most can not be ran either way without modifications. Running a pump for alcohol is necessary with some thirsty motors, it doesnt have to be just a big motor but most running a pump are cubs running 400 feet or more or bigger CC builds. Running a pump can be a pain at times to get some carbs to not leak but usually isnt a huge deal. Quote Link to comment Share on other sites More sharing options...
fbt551 Posted August 12, 2014 Author Report Share Posted August 12, 2014 This is what im running 39mm was told theyre for pump but not sure how to check that does the nipple inlet have anything to do with it? I have others that face up Quote Link to comment Share on other sites More sharing options...
sprinklerman Posted August 12, 2014 Report Share Posted August 12, 2014 Look like pumpers to me. Usually pump carbs have the fuel inlet facing down 1 Quote Link to comment Share on other sites More sharing options...
fbt551 Posted August 12, 2014 Author Report Share Posted August 12, 2014 Look like pumpers to me. Usually pump carbs have the fuel inlet facing downThats what I was told can I just change float and needle to make them gravity? Quote Link to comment Share on other sites More sharing options...
SOUTHTHIRTY Posted August 13, 2014 Report Share Posted August 13, 2014 Nope.. Quote Link to comment Share on other sites More sharing options...
SOUTHTHIRTY Posted August 13, 2014 Report Share Posted August 13, 2014 Run a pump...much better. ..and makes purging super easy Quote Link to comment Share on other sites More sharing options...
n2otoofast4u Posted August 13, 2014 Report Share Posted August 13, 2014 Are you trying to run gas or alky? Quote Link to comment Share on other sites More sharing options...
special06shee Posted August 13, 2014 Report Share Posted August 13, 2014 Silly question, but how does a pump make purging easier? Quote Link to comment Share on other sites More sharing options...
trickedcarbine Posted August 13, 2014 Report Share Posted August 13, 2014 (edited) Between the A&S logo,downward nipple, and the drilled main I'd bet those are definitely alky pump style carbs. If you want regular carbs, sell or trade those. Edited August 13, 2014 by trickedcarbine Quote Link to comment Share on other sites More sharing options...
trickedcarbine Posted August 13, 2014 Report Share Posted August 13, 2014 Silly question, but how does a pump make purging easier?Quick connect from tank to pump line. Pull from tank put on purge can. Pulls it quicker. Quote Link to comment Share on other sites More sharing options...
SOUTHTHIRTY Posted August 13, 2014 Report Share Posted August 13, 2014 U purge to thr pump... 1. Hose...much easier than 2 hoses Quote Link to comment Share on other sites More sharing options...
fbt551 Posted August 13, 2014 Author Report Share Posted August 13, 2014 Are you trying to run gas or alky?Running alky on a 350 t5 pipes gotaset of 34pjs now but have this other set of 39s strictly drag bike Quote Link to comment Share on other sites More sharing options...
n2otoofast4u Posted August 13, 2014 Report Share Posted August 13, 2014 The 39s are going to be way big. I don't care what kind of porting you have, with T5's you aren't going to need 39s. What is the rest of the bikes setup? There's plenty of people here that can get you in the right direction. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.