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i have been told by a performance place that when putting in rx7 550cc injectors i still require a resistor pack however i thaught that was only for low impedence injectors as rb20 is high, the rx7 ones are also high so will these fit in without to much hassle????

Secondly what is the correct part number?

Last if i install them myself can i drive to a dyno(its pretty far though) i dont have a luxuary of a powerfc but i do have a remap ecu i just need to et tunned once are in?

thankyou :(

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yes. if they have a bosch(square plug) there s4 low impedance

if they have a denso (oval plug) there s5, both are reddy pink.

i thought 20s had a droping resister. factory ones are low impedance any way arnt they?

I would talk to your ROM tuner first, cause I bet they wouldn't recommend the 550cc. And if they do they obviously havn't tuned on them before. Both my boss and I have had trouble with those injectors when tuning factory ECU and I also know that Martin Donnan had the same problems down south, very shite low pulse width control. Rotories dont care because they just drink fuel.

I would talk to your ROM tuner first, cause I bet they wouldn't recommend the 550cc.  And if they do they obviously havn't tuned on them before.  Both my boss and I have had trouble with those injectors when tuning factory ECU and I also know that Martin Donnan had the same problems down south, very shite low pulse width control.  Rotories dont care because they just drink fuel.

I also agree with rob82 comments as Matt Spry tried tuning them for my last R32 with factory ECU remap and had the same problems. Took them out.

Cheers

I'm running these red tops on my r32 with a remap and they work fine other than a rough idle.

This could be rectified with a bit of messing around with the ecu idle control values but I havent really had much time to do it yet.

wat kind of power can you make before these injectors start to run out of flow?

I think they flow to about 560cc each From memory so about 560HP@flywheel?

As long as the fuel pump is up to the task of course.

well my tuner is not recommeending these as too much mucking around, well a question for u all i have asked red drifter thanks for ur help but, my prob is at the moment car is so shitty off the line after remap i got a fmic,14psi( can xtract ne more with out fuel), hiflowed t3, xhaust,malpassi rising fuel reg, big fuel pump and all the other usualls, would i be better off getting a proper engine management or these injectors to cranck up the boost

well my tuner is not recommeending these as too much mucking around, well a question for u all i have asked red drifter thanks for ur help but, my prob is at the moment car is so shitty off the line after remap i got a fmic,14psi( can xtract ne more with out fuel), hiflowed t3, xhaust,malpassi rising fuel reg, big fuel pump and all the other usualls, would i be better off getting a proper engine management or these injectors to cranck up the boost

GTR injectors (444cc's) are the most common upgrade, you just need to get a GTR ballast resistor pack to go with them. They flow enough to reach the limit of standard RB20DET internals. The Standard ECU (remapped) won't have any problem running them.

:) cheers ;)

Edited by Sydneykid
after a tough choice i thuaght i have heard too many bad stories with the rx7 injectors so i got hks550cc ones(alot more pricey) instead lets hope all goes well. pppft i doubt it

Are they HKS 550cc's injectors for an RB26 or for an RB20?

:) cheers ;)

S5 inj + PFC work fine.

However @ idle even tho it doesnt sound to bad except for the ocassional pop they need to be tune quite rich AFR.

The spray pattern on Rx7 inj is more like a squirt rather than a mist compared to a piston injector so tunnig for them to spray small amounts of fuel(@ idle) its kinda tricky. And hence requires the AFR to be slightly rich. My AFR @ idle was ~ 12.0 when they are usually around 14.0.

Rotaries have a deflector which splits the spray in half for a more even distribution, obviously piston motors dont have these.

Best bet is to go for GTR inj. or if budget allows go for SARD, HKS...

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