steveyz250fpilot
Banned
- Location
- Huntsville, Alabama
A single carb on an engine that size can be more than sufficient.
5mil stroker jetting for a single 48 riva carb?
- Thread starter masterblaster
- Start date
A single carb on an engine that size can be more than sufficient.
masterblaster
X-H2
yea I had a 60 jet in it for a restric,didnt matter though even without it,I was running a clear return line to see what was going on and it wasnt sending back fuel at all.
was thinking maybe the fuel pump isnt keeping up,the filter isnt flowing enough,or the pulse fitting i installed was a little to small on the ID. it was 1/4 OD brass water line taped and threaded in? still waiting on the 175 main to try before i mess with any this other stuff
was thinking maybe the fuel pump isnt keeping up,the filter isnt flowing enough,or the pulse fitting i installed was a little to small on the ID. it was 1/4 OD brass water line taped and threaded in? still waiting on the 175 main to try before i mess with any this other stuff
masterblaster
X-H2
got the blackjack dialed,with huge jets,180,150. the riva is still boggin 90% of the time with the same jets posted above... the other 10% its hitting way harder than the BJ but is also running out of fuel in the top end 100% of the time when it does hit.
the only way I can get the riva to hit is to let the ski idle for 5 to 10 secs,once the carb loads up its ready for a SERIOUS blast for about 3 to 4 secs till its falls on its face and runs out of fuel again,this is one PITA carb to tune
the only way I can get the riva to hit is to let the ski idle for 5 to 10 secs,once the carb loads up its ready for a SERIOUS blast for about 3 to 4 secs till its falls on its face and runs out of fuel again,this is one PITA carb to tune
THRUST
ThrustInnovations.com
- Location
- royal palm beach florida
what needle and seat do you have in there . I would run a 2.5 with a 65 gram spring and retest if you are not there already . also double check the carb and parts for any overlooked problemns
waxhead
wannabe backflipper
- Location
- gold coast
Have you considered that the engine may be restricted by the intake so badly that the carb is not getting enough pressure drop across the jets to allow it to run correctly
Are you using the 650 kawi intake manifold with adaptor plate
Are you using the 650 kawi intake manifold with adaptor plate
masterblaster
X-H2
Virgin...its a 2.5 and ive tried 95 and 115 springs with these new jets,I tried the 65 with the 155,150 jets and got no results so was trying higher pop off to see if it would make a diff
wax.its a bcf intake ported out to 48 and gasket matched. I could try even bigger jets,but I would thing that 180,150 is bigger than anyone else runnin a riva carb already?
wax.its a bcf intake ported out to 48 and gasket matched. I could try even bigger jets,but I would thing that 180,150 is bigger than anyone else runnin a riva carb already?
no fuel is coming back through the return line?
sounds like a fuel pump issue.
(i didnt read the entire thread.... just skimmed)
sounds like a fuel pump issue.
(i didnt read the entire thread.... just skimmed)
- Location
- s florida
I think you got some other issue going on there!
- Location
- s florida
Have you checked your check valve on the tank????
masterblaster
X-H2
how would the check valve effect this?
went out today with some other junkers and we noticed that runnin the ski against the bulk head hood off no prok,looking down into the carb at WOT after letting it idle for 5 or more secs it would hit hard and fuel flow was very smooth,then again if you brapped the throttle more times,the fuel coming out of the bulls eye looked like it was fluttering when the ski is not hitting just feels like a half throttle blahhhh even at WOT,would the fuel pump be causing this?
went out today with some other junkers and we noticed that runnin the ski against the bulk head hood off no prok,looking down into the carb at WOT after letting it idle for 5 or more secs it would hit hard and fuel flow was very smooth,then again if you brapped the throttle more times,the fuel coming out of the bulls eye looked like it was fluttering when the ski is not hitting just feels like a half throttle blahhhh even at WOT,would the fuel pump be causing this?
masterblaster
X-H2
they are up next,would have like to have had the riva dialed first though,to see what each is capable of,the black was dialed,but not really that impressive compared to the few secs I was able to get the riva to hit.If I get the same diff between the hit of riva and dual 48s,it will be ridiculous nasty
There really should not be much of a difference between the two carbs. If one runs better is more than likely the jetting is better suited for that carb and your engine combination. What I ask is why are you having to run jetting that is not common and when you get it close it either hits and then runs out of fuel or it does not respond well but does not run out of fuel. Do you know what nozzle size you were running on the MRD. I think even after using the duals you will be back with the MRD. At least on this engine.
masterblaster
X-H2
there was a big diff between the BJ and the Riva,thats all I can say,the BJ did hit well and was still close to lean but never ran out of fuel completely. The jetting isnt abnormal for a big single on a stroker from what im told,its suckin a ton of air.
Im hoping the dual 48 full specs will do the trick,but I have the mrd being customized with a much higher intake for the proks and new pop offs with a group k air water separator coming as well. Will compare the fuel use between the 2 setups and run the best hit for the least fuel used,we have a long ride to our surf spot.
why would the fuel be pulsing in the riva,this is the issue?
Im hoping the dual 48 full specs will do the trick,but I have the mrd being customized with a much higher intake for the proks and new pop offs with a group k air water separator coming as well. Will compare the fuel use between the 2 setups and run the best hit for the least fuel used,we have a long ride to our surf spot.
why would the fuel be pulsing in the riva,this is the issue?
masterblaster
X-H2
anyone else have any idea on the pulsing fuel issue?
masterblaster
X-H2
?
masterblaster
X-H2
Got the 48 mil dual full specs on today with remote fuel pump r&d intake ported for 48s r&d angled intake spacer and v force 1 reeds,No more runnin out of fuel issue,no more bog,throttle response perfect every run. low mid and high.deff came on stronger faster than the single blackjack 46.
The only issue now is its taking a little longer to hit really hard than I like,its got a strong bottom but it really comes on HARD about a sec or 2 after I would like.mid range is sick. It felt and looked like the bottom was still lean though at 1 1/2 turns out on the bottom end jet so going to try jetting up the pilot a tad.gotta call ed and see what he recommends.... its currently at
1.8 needle and seat
135 high
125 low
22psi pop off
may be over proped for what i want,solas 15/18 with unknown pitch work.gonna try and run a 13/15 concord if the jet doesnt do it. and if that doesnt do it bite my lip and up the compression a tad.
The only issue now is its taking a little longer to hit really hard than I like,its got a strong bottom but it really comes on HARD about a sec or 2 after I would like.mid range is sick. It felt and looked like the bottom was still lean though at 1 1/2 turns out on the bottom end jet so going to try jetting up the pilot a tad.gotta call ed and see what he recommends.... its currently at
1.8 needle and seat
135 high
125 low
22psi pop off
may be over proped for what i want,solas 15/18 with unknown pitch work.gonna try and run a 13/15 concord if the jet doesnt do it. and if that doesnt do it bite my lip and up the compression a tad.
waxhead
wannabe backflipper
- Location
- gold coast
so duals got more hit than a single
Man who would have guessed that
Man who would have guessed that
masterblaster
X-H2
not really the point there sherlock,but late mid to top end hit felt sim
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