I'am getting ready to install my BNR stage 3 turbos in a week or so and wanted to know what injectors I should use. Primary and secondary? Brand and size?
Thanks,
Erik

 

Injector size is dependent on what boost levels you will be running. I would wager to say that with the BNR twins, the best setup would be the stock 550cc primaries with enlarged secondaries (850cc bored out to 1200-1300cc). That setup will still allow you to pass smog and will supply enough fuel for you to run any level of practical boost with the BNRs. I assume you have a Power FC or other programmable ecu to tune the car with?

 

Rynberg, if I'm not worried about emissions, shouldn't I upgrade the primaries as well? I'm thinkin supra (denso) fuel pump, 850 primaries (the stock secondaries relocated) and 1300 denso secondaries.

I'm lookin @ running 15 - 18 psi

 

I use 550/1600 and under ~18 psi My inj duty cycle is about 80%

 

850's + 1300's will give you 4300cc/min max, 550's + 1600's will give you the same cc/min.
The benefit of the latter being that you won't need to change your secondaries should you push bigger power and you won't need to mess with the primaries either (for now).
The supra pump is very good for your needs, even better when you add the rewire mod.

 

I'm with you on not needing to change the secondaries if you have 1600s...but do you ever really need to go larger than 1300s if you're still running twins (upgraded)? I thought that was really only an issue if you're going w/ a big *** single turbo hehe

Also, for larger applications, your primaries being only 550s doesn't limit you at all? My intuition would tell me that if they're just that - your *primary* injectors, you'd wanna make sure they weren't a limiting factor...

Or does that not really come into play, since the ECU (PFC in this case) can be mapped to adequetly control total fuel delivery via coordinating primaries and secondaries? (is 550s would never be a problem)

Last thing...what's the rewire mod? Got a link to it?

Thanks

 

550cc primaries are good for over 400rwhp....the ecu just switches in the secondaries whenever you reach a certain duty cycle on the primaries.

 

Plus, some people report a lumpy or bad idle when getting bigger primaries.

I don't have any firsthand info, I've always kept stock primaries. So don't hold me to it.

 

Thanks, I think I will go with stock primaries with 1300 secondaries. Also a bought a Walbro fuel pump, is that ok for my set up?

 

Be careful with the 1300's. There have been a few threads detailing people who's engines have blown because of these injectors.

Do a search for 'rc engineering' or 1300 if the forum will allow.

 

So w/ a PFC, can you program it so the ECU switches over to the secondaries at a set duty cycle? (if you don't wanna run the primaries at greater than say 85%) or is that not something that you control (the duty cycle @ which they switch over)?

 

Be careful with the 1300's. There have been a few threads detailing people who's engines have blown because of these injectors.

Do a search for 'rc engineering' or 1300 if the forum will allow.

But others have had no issues whatsoever with them.