I recently upgraded my fuel system from the stock rails and injectors to a stock 550cc primary, KG rail with 1600cc and an aeromotive fpr.
I did the change mainly because my stock system had a leaky fpr, and I thought the secondaries were stuck open. I ended up fixing the problem and it was an electrical problem.

ANYWAYS...I don't have the money to complete the single turbo setup, so I was hoping to change the 1600cc's back to 850's but wanted to keep the KG rail. My haltech is already tuned for the stock setup so would the tune run into any problems running a Seimens 850 top feed injector setup (rx7store injectors)? I would think it would be the same as the stock side feed but wanted to double check before purchasing them.
Thanks

 

The 850's will work.

 

Perfect. And to double check, I only need the O-rings and the LIM spacers for top feed injectors correct?

 

The 850's will work but the tune will most likely not match.

thewird

 

Can't you just use the 1600's in this setup? They just wouldn't be working very hard.. Unless the main focus here is MPG. I am planning on upgradeing my fuel system to a setup like this before I get my turbo and running it NON-Seq. I am curious now if I will have too much fuel for my current setup.

 

As soon as I installed them and I go WOT, it goes extremely rich, bogs n such. I did a data log and it said the secondary duty cycle was around 35% at 6 or 7psi.
I might have them installed wrong, but even if I kept them, a retune would be a must.

 

You could try taking some fuel out.

thewird

 

Find where it gets rich in the text map and then change em that way, or the 2d or 3d? I'm sure I could figure it out, just need someone to drive I suppose haha

 

You said your haltech is tuned for the stock setup?
now this may be a stupid question,
But did you change the tune to accommodate the 1600's?

 

That's why I want to go back to 850's in the secondary, I really have no idea when it comes to fuel and timing tuning. I can install and get it running n such, but have not attempted to tune yet.
I'm not even shooting for high hp right now, I just want to make some practice events.

 

ah, thats definiteley why its bogging down/running pig rich then.
The tune would need to be changed for the siemens 850cc injectors (aswell as the 1600's), which i assume are low impedance versus the stockers which are high impedance.

 

Yeah for sure, I just have no idea where to start to be honest and have no one around me to lend a hand.