staging problem
 

Well, i have a little problem, i have map tuned with 7psi on the primary injector with a rev cut limiter set up to 5k and the car running great like no prob.

When i`m changing the map, i put my stage at 3k rpm and 5hg. While running, and the staging is coming up, my engine start to lose power and bug a little..

While the engine is bugging, i succed to tune at 13/1, but i still don`t have more power.. It feel like i got only one rotor running! What could be the trouble?

what injectors are you using?

ok , my setup is a Rx7 T2 1987 with 13b-re stock port rebuilt with a t61 turbo . injector is 550 stock on primary and 1600cc (turbo Precision From JRP) and my standalone is microtech ltx-8s.

did you take your percent stage up to 95%

Ok, here we go…

He’s one of my friends, and English is not is first language so don’t be too hard ;)
So, yeah, we’ve been playing around with this staging issue on his car.
The problem is that we can’t get a good staging. The last time we went out to try and get this right, we almost succeeded but not. We’re running 550 primaries with 1600 secondaries. Staging point was set at 2500 rpm and 5”hg and set to 98%. Right before the staging point I had a lean spot (around 14.5) and right after, on the 0” screen, AFR went back to 13.

What stumbles me is that as soon as the staging kicks in, the car gives a totally different response. It looses a lot of power and doesn’t sound right. Almost like an engine running only on one rotor. We verified the secondaries using a LED, but we only verified the front one and it does open. Next thing to do will be to verify both of them. Could it be that only one secondary is opening? Thus sending fuel only for one the rotors?

Another question. Let say I set the sating point to 3000 RPM and 0”hg.
When in matrix mode, should I cut my inj. opening time on the 0”hg OR on the 2psi box?
I’m having a hard time with this, I taught that the staged values should be entered AT the set staging point, in this case @ 3000 & 0 but now I’m not sure. Should it be @ 3500 & 2 psi right after the set point or directly on the said set point?



Any help is appreciated.

nobody have idea???

Ok, I have some updates on this.

It was nice and warm this week-end so we went out playing with the beast.

Here's what we've found:
Only one of the secondaries is opening. The rear sencondary never comes on. We verified the wirering, all, good. It's seems to be the ECU inj driver which is faulty. What could be the cause of this weird issue ??

Anyway, we wired both secondaries to the front secondary driver and now it goes. I'm wondering tho, are the secondaries pulsing together or are they phased 180° apart?

ideas
 

I have a Microtech LT8S (similar to your ECU i think but with no igniters) on my FD (with GT35R turbo). I also used to run 1600cc secondaries too, these were made by Bosch and had an impedance of around 4-5ohms. If you connect up 2 of these 1600 inj's to one of the secondary inj outputs from the LTX-8S, the impedance will then be half of 4-5ohms which is 2-2.5ohms. This very low impedance COULD DAMAGE the secondary inj 'output' you are now using! Also the injector firing order would be 180degrees out of phase, I think. Can you check your 1600 injectors impedance with a meter?

Also try the setting the staging vac/boost value to a point in between 10" and 5", as on my FD it stages a lot more smoothly. I'm not sure if this is due to bad interpolation of mapping points on the ECU, or some other reason.

When you first start tuning the engine, I found it much easier to map in NORMAL mode (not MATRIX). See the ECU manual for details. Set up your RPMwot and RPMcrs values, then on WOT you can adjust the fuelling at the various rpm's until you get the AFR's you want (eg. 11:1) . Just be very careful NOT to underfuel your engine when on boost, otherwise bad things might happen!

A useful way to check if your injectors are all working is to set the 'Config' value to ZERO. This then runs the ECU in diagnostic mode. All the injectors will then open and close quickly (ie. as if the engine is running at approx. 4000rpm). You can use a length of hose right next to each injector (as a stephescope) to 'hear' the inj's switching on/off. Just remember to set the 'Config' value back to the original value ie. 4CYL.

BTW when is a T61 supposed to come on boost? Isn't a T51 big enough for you?

Hope this helps,

Adrian