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-   -   Stuttering? (https://www.rx7club.com/1st-generation-specific-1979-1985-18/stuttering-259455/)

Rotofire 01-11-04 12:15 PM

Stuttering?
 
I just bought a carb (weber45dcoe w/ RB intake) i got the fuel regulater but not the fuel pump....no i stutter at top end and can't get my rpms past like 5K in third gear the whole car shutters and slows down it's like the enigine is choking itself off. i also have to big of jets in there for the 12a engine. so i do need to get smaller ones

Jayroc~do you have those jet sizes i needed....and where can i get them? hopefully that and a new fuel pump will help. :confused:

1ltr8etr 01-11-04 12:24 PM

Could be the fuel pump, but I would first check the fuel return line setup. Do you have any kind of restrictor in the return line - like a fuel jet (or anything really) that will mostly block the return line but let some fuel through. If not, then that could cause your sputtering, as you are losing too much fuel pressure to the return line and don't have enought to keep the float bowls full after a prolonged run at higher rpms. This was the problem with my Mikuni when I first put it on (not sure if webers have the same type of fuel feed) and a 1 cent small screw worked into the return line fixed it - note, don't totally block the return line or you might have a flooding problem when you shut it down, as there is no relief for pressure in the line and fuel will seep into the carb throat. Anyway, check this out before you spend big bucks on a new fuel pump - the stock pump puts out in the range of 3.5-4 psi, which is fine for a stock ported engine, even with an after market carb.

Rotofire 01-11-04 12:45 PM

my fuel return line is completely closed/pinched off, would that be it? what would i have to do to fix it.....i just got my carb on yesterday so i haven't had time to finely tune it yet.

Rotofire 01-11-04 06:43 PM

anybody know?

mazdaverx713b 01-11-04 06:46 PM

if the return line is pinched it may feel like the carb is getting too much fuel or is flooded, possibly resulting in stuttering.

Rotofire 01-11-04 07:55 PM

alright, thanks


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