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How's it? I have myself an RB20DET, It has FMIC, T04/T3 turbo, LTx12 microtech, Bosch 040, Malpassi rising rate fuel reg. Now the dillema I am facing is that I have Rx7 non turbo injectors fitted (460cc). The tuner had to run the car rich at idle due to dropping the cycle 1msec caused the car to hesitate and hunt. This is what he told me. This is causing problems, shitty fuel consumption as 90% of my driving is fairly local and the excess fuel seems to be washing the bores. The RB has been rebuilt and I think the overfueling is causing more damage than good. The tuner recommends that I drop injector size, so I have got my hands on a set of CA injectors to fit as they about halfway between stock (RB20DET) and what I have now. I am afetr opinions should I 1/Get him to try again with the 460cc's? or 2/Get the CA injectors cleaned and flow tested and fitted/tuned? What do you think? The tuner is fairly well respected as he has the Ford (hahaha) performance contract doing the new turbo falcons and v8's. Thanks for your opinions Pete

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hi OMP,

don't know if u saw my reply in the other thread where u posted, so here goes -

i'm running 550cc injectors on my RB20, ECU is AP Engineering PFC. Injectors have gone up just over 100%, but my tuner has done an awesome job with the staging, idle, etc - tuning work. Running a HKS GT2530 turbo, and I only run around 1 bar of boost so we're probably talking about a similar power range, tho I'm probably making less power heheh. I don't think the injector size is too big - my 550cc injectors are bigger than yours and with careful tuning, I even have excellent fuel economy on highway (230kms on just half a tank) and acceptable town consumption - 250-350kms. perhaps there is some issue with the specific injector itself? lag time or something? I don't know much about injectors :)

How's it? I have myself an RB20DET, It has FMIC, T04/T3 turbo, LTx12 microtech, Bosch 040, Malpassi rising rate fuel reg. Now the dillema I am facing is that I have Rx7 non turbo injectors fitted (460cc). The tuner had to run the car rich at idle due to dropping the cycle 1msec caused the car to hesitate and hunt. This is what he told me. This is causing problems, shitty fuel consumption as 90% of my driving is fairly local and the excess fuel seems to be washing the bores. The RB has been rebuilt and I think the overfueling is causing more damage than good. The tuner recommends that I drop injector size, so I have got my hands on a set of CA injectors to fit as they about halfway between stock (RB20DET) and what I have now. I am afetr opinions should I 1/Get him to try again with the 460cc's? or 2/Get the CA injectors cleaned and flow tested and fitted/tuned? What do you think? The tuner is fairly well respected as he has the Ford (hahaha) performance contract doing the new turbo falcons and v8's. Thanks for your opinions Pete

Whats the Microtech like? I am saving for one of these at the moment, and will be running a similar setup, but with GTR cams, exhaust manifold and GTR injectors

I am going to get the LT-12S though, but interested to hear what your experiences are

Chris

P.S - from every big injector/programmable computer setup I have ever seen with Idle/low speed problems, it always comes back to the tuner. Was it tuned via hand controller or via Laptop? Freebaggin has a LT-12 in his R33, running 280rwkw, and has just recently had a retune utilising the Matrix mode tune, and from all reports it drives really well now, maybe PM him

ill tell you what wont help.... i was going to use some rotary injectors in my rb20 untill i realised a major factor.... rotors love fuel... the more u give em they just keep going .... any rotor injector had basically no or just a really crappy spray pattern.....therefore they arent really suited to a piston engine.... so i went for gtr injectors myself and the 4g63 are another good option.....im not saying u made a bad decision but what i am saying is that it makes it harder to tune idle/low revs and also i use about 35 psu fuel pressure thats about all u need...... get everything else sorted dude then maybe try amd gtr or similar injectors....this is just the opinion i have formed after listening to several ppl in the know and trial and error im not saying im 100% correct...9but i hope i am :D )

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