OK.

so in the injector setting on the commander the screen looks like this (or very clos... but you should get what I'm saying...)

FR-PR %100 +0.00
FR-SC---------+0.00
RR-PR %100 +0.00
RR-SC---------+0.00

PR 550cc
SC 850cc


So here is how I set mine up. Does it look correct? I have 850 primaries.

FR-PR %64.0 +0.04
FR-SC------- +0.00
RR-PR %100 +0.04
RR-SC------- +0.00

PR 850cc
SC 850cc


Did I do the lag correct? I assume since there are only two options for %, that the first is for the primary in which case they should be around %64. Then for the lag, you can adjust all four injectors? So I go over to the left column and choose the PR injectors and go all the way to the right.

Should I be leaving the "CC" settin on 550? Shouldn't the % be compenstating for the larger size? What is the purpose of the "cc" setting?

Hopefully I'm kind of clear on what I'm asking.



Also... any other settings I should be changing to run these 850's? I need to be able to limp the car around, but tip-in is terrible and it hesitates the minute I hit 0 vaccum.

 

Most need negative lag to lean out the idle so start with -.04.

Since when is 550/850 = .64? My math says .647.

 

I was just following the reccomendations in a long thread about 850s.

So should I try -.04 and I guess .647%?

 

what should my AFR's be at idle?

 

i couldn't get 64.7% on the commander so I did 64.5. It idles a bit better with the -.04 but it still runs like **** upwards of 2krpm.

 

I bet your rear spark plugs are wet. You should consider changing the rear primary injectors to match the front

FR-PR %64.0 +0.04
FR-SC------- +0.00
RR-PR %100 +0.04
RR-SC------- +0.00

 

thats the info I was looking for.

I was unsure if that was the % for the secondary injectors.

Thanks.

I will go do that right now and report back.

 

It is actually for Primary rear (RR-PR or ReaR-PRimary),
Primary front (FR-PR or FRont-PRimary)
but yes, change that value to match your front primary and you should be close enough.

 

ok... reporting back.

set both % to 64.5 and the car runs extremely better. Tip-in is still a bit laggy but it revs much more free and dosen't hesitate anymore. I re-learned the idle as well and it sound way more healthy.

steve, do you suggest -.04 or +.04. I've seen a few different recommendations. Also what would you recommend for INJ vs tps.

I ran -.04 for a few laps around the block and then switched to +.04 and it seemed to run better with +.04 but I would appreciate some professional input.

 

I use -.04 for the (side feed) 850cc but if you are running (top feed) 850cc, they are totally different and proabably need around .20 lag time

You will also need to adjust your (accelerated injector) for better tip in.

as for INJ vs. TPS, I wouldn't touch it and leave it at 100% since it would involve remapping everything in the basemap.

 

they are stock 850's. so I will try them out at -.04 and relearn it again.

I will do a bit of reading on the accelerated injector and see how it goes. is it available through the commander and under what menu or do I have to install my datalogit (just have it sitting in my room right now).

thanks for the advice I appreciate it.

 

You can change the value with the commander. I think it says (accel?). You will see a table similar to this

rpm amount decay
5000 7.500 1.000
4000 7.500 1.000
3000 7.500 1.000
2000 8.000 1.800
1000 6.500 2.000

 

ok.

is that the stock settings you posted? or what you recommend for 850's? My car's parked for the evening so I don't want to go down tot he parkade to check. I am going to do a bit more fiddling tomorrow.

 

those are stock settings. You will most likely change 1000 and 2000 rpm values.

 

ok thanks. I will see how it goes.

 

Interesting! My top feed 720 primaries didn't need negative lag at all, and I ran .03 on my previous setup and never had a problem leaning them out. I didn't realize that there was such a difference between the two types of injectors.

This is just my experience, but I have actually found that INJ vs TPS has the least effect on all the other AFR's in terms of making you dump in fuel when you don't want to. The trick is to rescale the lower % values so that you get a more linear application of fuel. INJ vs Accel TPS1 can really screws things up if you mess with "input" setting especially, which can help tip-in but does create a lot of extra work retuning the low load portions of the map.

Here is what I am running:

INJ vs TPS
TPS % - Setting

89.8 - 1.063
79.7 - 1.055
69.9 - 1.055
59.8 - 1.055
25.0 - 1.047
10.2 - 1.023

vs the defaults:

INJ vs TPS
TPS % - Setting

89.8 - 1.00
79.7 - 1.00
69.9 - 1.00
59.8 - 1.00
50.0 - 1.00
39.8- 1.00

I find this table can be very precise after you play with it for a while.

 

Can someone explain what these settings do?

 

Since u guys talking about laggin injectors, does anyone know what is the correct setting for 550 primary, 1300 secondary setup?
Thanks
Khris

 

Settings 5.

 

maybe this thread will interest you!
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/850ccm-primaries-how-do-right-900495/