Well I just sent payment for the S5 V1.7 with the 550cc/720cc combo.

Question I originally had 550/680cc with the 680cc resistor pack mod wired into the ecu. Can I use the greddy 720cc drop in or do I have to change the resistor pack.

Second question. Why can't there be an upgrade featuring these 680cc?

Third question.
What boost levels will I be safe at with the 550/720cc Retek.

Fourth question is the timing and fuel maps completely untouched under stageing?

I also have a Safc connected but will have 0% correction applied once I get the remapped retek.

thanks,

 

Ian...If you have the 'good 680's"they flow way better than just 680cc.
so Honestly they are as good as the 720's.
(case and point,look at Hai Tek 7's For Sale thrad where he had 680cc injectors with a Flowsheet Up For Sale.I bought them).
If the 720s are Lo and you have the resistors in place to act as HI at the Ecu then YES they will work.(that is if the s5 Ecu is supposed to see HI.)

 

Just to make it clearer: S5 ecu runs HI impedence injectors w/o resistor packs

S4 ecu runs LO impedence injectors with resistor packs.

As I understand it you can run HI imp. injectors on s4 if you just bypass the resistor packs. (this could burn up the injector driver in the ECU???)

With low imp injectors you must run a resistor pack on s4 or s5 ecu

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/injector-impendence-858567/

http://www.kpsec.freeuk.com/imped.htm

(2)

(3) As a general guide, http://www.rx7.com/cgi-local/2ndgencalc.cgi, no way are they exact. Figure about how much boost will get you to that hp or a certain hp. Stay on the conservative side or push the limits if you have the funds.

(4) I belive the fueling only allows for running stock turbo at or below 12psi, timing is stock, but above 9psi it retards timing 1 degree per psi above 9psi.

What turbo are you running? What mods do you have?

Good luck and have fun, I started with V1.5 and had a lot of fun with it!

 

I will send my 680's to get cleaned and flow checked. I don't want to risk lean spots because the 1.7 requires 720cc and is mapped such.

 

Engine is completely stock with stock turbo. Planning this as a daily driver with some track days. I have another RX7 with a huge turbo and ems etc etc that I can take when I need the nasty loud and complicated gizmo's

Since I am paying for the Rtek I thought I would just go with the 550/720cc upgrade so I can at least run some decent boost for those days stock boost levels just don't cut it I may just run 10psi daily and leave it at that. Just want to make sure I am not getting close on duty cycle. I think I was able to run on my s4 back in the day when it was stock 10psi with no issues on a remapped ecu.

 

Sent you a Pm of the 680 flowsheet.

 

hey guys i gota question also i dont want to thread jack here... i have a 87 stock turbo car and i just eamiled a guy that seals injectors he wants to know if there high or low impendece could you guys tell me how to fig it out. i plan on buying the setup for the 1.7 setup .... thanks

 

It depends on if you have an early 87 or late 87. The ECU needs to see high impedance either way.

Look in your engine bay near the passenger headlight and you should see a box that has a big yellow plug going to it.

 

OK y does it need to see high can u explain it a little bit do we have to use high impedance so that we don't hurt the fuel injector driver in the ecu ?

 

Yes, the injector drivers in the ECU are made for high impedance. Putting low impedance injectors on without the resistors draws too much current through the drivers and will blow them.

 

so no matter if i have high or low on the car right now the best thing to do if i were to upgrade the injectors would be to put high impendence 550 and 720s on it with the 1.7 chip ?

 

my car was built in 08/87 so the dealship says i would need dark pink injectors if i were to go stock if i could find remans