So after my rebuild, i put my stock injectors back in when installing the motor again. But I ordered a pair of bosch 1600cc low-imp monsters to replace my secondaries, haven't put them in yet though. I'd like to install them before i go in for a tune.

What I'm asking is for someone to confirm that i do have stock high-imp injectors in my 90' Turbo II. The stock ones are Denso 550cc reds.

...And is it possible to use high-imp primaries but low-imp secondaries in the same car?

If anyone knows where i can find a write up of how to solder in the resistors, that would be awesome. Thanks.

 

In short yes

You can get a stock resistor pack and wire that in to just the secondaries

I don't remember the link to the "resistor" thread

Pulled this directly from the faq

What size injectors does my RX-7 use? What colour are they?
Year Engine Plug Size Colour Part #
84-85 13B NA, low square center, 680cc, orange, 195500-0900
86-87 13B NA, low square center, 460cc, red, 195500-1350
86-87 13B Turbo, low square center, 550cc, tan, 195500-1370
88 13B NA, high square offset, 460cc, purple, 195500-1350
88 13B Turbo, high square offset, 550cc, purple, 195500-1370
89-91 13B NA, high oval center, 460cc, red, 195500-2010
89-91 13B Turbo, high oval center, 550cc, purple, 195500-2020

 

okay, if i understand this correctly,
... you mean i can find a stock resistor pack from an earlier car that runs low-imp injectors and just splice those into the wires which normally run to the secondaries?

 

you can wire in separate resistors. I would not recommend the radioshack ones. They are usually 10 ohm and that's not going to help injector staging hesitations. The factory resistor pack is 6 ohm. You can also order 6 ohm resistors.

But what are you using to tune these injectors? 1680s are too big for anything but a standalone (Haltech, Microtech, Megasquirt, Power FC, etc).

 

Well i was eventually gonna go with a power-fc.
Stock ecu for right now.
So basically i should wait to put them in anyway? Stock system won't support these?

 

The stock system is tuned for the stock injector flow rate. With the stock system, the 1600cc injectors will cause the engine to run extremely rich during acceleration past 3600-3800rpm, causing bogging and/or bucking, bad gas mileage, and carbon fouling on the spark plugs and engine internals.

Also, you will need an upgraded fuel pump to run those injectors to their potential, and a nice Aeromotive or SX fuel pressure regulator and gauge is a good idea.

 

Do yourself a favor.

Wait until you get a Power FC. Then you can solder the resistors into the adapter harness and not even to hack up your factory harness at all.

you will never get the injector staging right on the stock ECU

 

listen to the man above me ^, he speaks the truth.
Also, do more research, you cant just slap an injectors thats 3 times the size of the stock one and pretend it to run good.

 

I just did this.Sort of In reverse
..Lo 550 Primaries with the resistor Pack on a N/a Harness(TII engine) .I bypassed the Secondary resistors in the pack to Run the HI Impedance secondary Injectors.(900's on an RTEK 1.8)
Look back at One of My threads,I asked the same thing,I had replies from Hailers.He posted some Schematics,and wire Coding for the Resistor pack.
This is a Do at your Own risk thing..
Arghx and Evil Aviator Know their Stuff,so anything they suggest is Pretty well Sound advice.
Cheers STYX.

 

I guess I'll wait. Even though i did put a walbro pump in (forgot to mention that), i still need an FPR for it so i guess it would be running really rich as it is.

At least i have a game plan now, thanks everybody.

 

do it right and get an injector driver