Mk1Daniel Posted June 22, 2015 Share Posted June 22, 2015 Hey guys have a 12abp starlet I want to get rid of. I'm having an issue where if I rev it up is misses and when it's driving I can't go full throttle until exactly 4000rpm or more otherwise it misses and pops. It's got a nikki 4 barrel with mechanical secondaries. I think it's a facet fuel pump. I have no fuel pressure reg so I'm thinking it's got too much fuel pressure. Compressions at 95psi. Any ideas Rotary guys or generally clever cunts? Quote Link to comment Share on other sites More sharing options...
kiwi808 Posted June 22, 2015 Share Posted June 22, 2015 At approx 4000rpm the secondaries open. Does it rev fine after 4000rpm? Quote Link to comment Share on other sites More sharing options...
shizzl Posted June 22, 2015 Share Posted June 22, 2015 mine was about the same and was over fuelling Quote Link to comment Share on other sites More sharing options...
Mk1Daniel Posted June 22, 2015 Author Share Posted June 22, 2015 Yeah can hit foot flat and it goes good after 4000. I also think overfueling. Cars not at home so just getting all the ideas I can before going out and working on it Quote Link to comment Share on other sites More sharing options...
Mk1Daniel Posted June 22, 2015 Author Share Posted June 22, 2015 Kiwi808 its mechanical secondaries Quote Link to comment Share on other sites More sharing options...
kiwi808 Posted June 22, 2015 Share Posted June 22, 2015 Over fuelling is probably the problem which is why it gets better once the secondaries open. Quote Link to comment Share on other sites More sharing options...
Mk1Daniel Posted June 22, 2015 Author Share Posted June 22, 2015 But the secondaries open whenever I put my foot down but I think I get what you mean Quote Link to comment Share on other sites More sharing options...
danger Posted June 22, 2015 Share Posted June 22, 2015 If its not an over fuelling issue maybe look at locking your dizzy? 1 Quote Link to comment Share on other sites More sharing options...
Mk1Daniel Posted June 22, 2015 Author Share Posted June 22, 2015 How would that help? Quote Link to comment Share on other sites More sharing options...
shizzl Posted June 22, 2015 Share Posted June 22, 2015 fixed advanced...doesnt the standard dizzy lag behind when you floor it with a ported motor, cant keep up... ignore my rusty rotor tech Quote Link to comment Share on other sites More sharing options...
Mk1Daniel Posted June 22, 2015 Author Share Posted June 22, 2015 Makes sense I guess. Quote Link to comment Share on other sites More sharing options...
ajg193 Posted June 23, 2015 Share Posted June 23, 2015 I'm just gonna jump in with some generic Starlet advice. Pull the motor, lower the car and drop a rotor in. /Lingpost Quote Link to comment Share on other sites More sharing options...
Corbie Posted June 23, 2015 Share Posted June 23, 2015 I'm just gonna jump in with some generic Starlet advice. Pull the motor, lower the car and drop a rotor in. /Lingpost It has a rotor... that's his problem. 3 Quote Link to comment Share on other sites More sharing options...
Mk1Daniel Posted June 23, 2015 Author Share Posted June 23, 2015 Hahaha. I got it super cheap because the guy thought it was blown up or something and a whole bunch of other issues. So he towed it to me. Got it driving in 5 mins. Compression tested mint. He was guttered Quote Link to comment Share on other sites More sharing options...
KKtrips Posted June 23, 2015 Share Posted June 23, 2015 Did you use a regular compression tester or a special rotary one. They are special because they have to read 3 compressions separately through one hole. 2 Quote Link to comment Share on other sites More sharing options...
oldrx Posted June 25, 2015 Share Posted June 25, 2015 As it is mech secondaries you prob need to mod the accel pump to get a bigger squirt as they open so much faster than vac sec its common to get a lean stumble. I've seen various combinations of; grinding the stops down, mod the linkage for a longer stroke, make a spacer between pump and carb body to increase the volume it can hold, drill out the passages in the ali two pronged squirter bit (cant remember correct name atm, will look it up), drill out the jet Have a look around rx7club.com May pay to check its operating at least to factory spec first; https://free-info-pages.com/rx7-carburetor-accelerating-issues.htm Quote Link to comment Share on other sites More sharing options...
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