Ocelot

Ok so basically due to some complications, my stage II hybrid from BNR for my 89' TII will be arriving VERY close to when i'll be leaving for school. Its being overnighted tommorow, meaning I should have it sometime thursday, and i'm leaving friday night so hopefully i'll be able to get the turbo/injectors to be installed before I leave. I was originally going to have it dyno tuned as well, but the way things are looking now it seems as if i'll be lucky to even get my car done before I leave.

So now this is where i'm at, i'll have the following mods on my car:

- S-AFC (I)
- RB 3" Turboback
- A'pexi Intake
- FCD
- BNR Stage II Hybrid Turbo
- 4x720cc Injectors

Now with these mods I was wondering if there is a S-AFC setting that I could get by on for now until I could take it somewhere to get tuned. Originally i'd only have to drive it a short distance to the place to get it tuned, but my school is about 7-8 hours away, so basically i'm looking at driving it down there to get started with school and all, then driving it somewhere to get tuned. Is there any danger to run with these things without getting it properly tuned and going on some basic settings?

- Brian

DerangedHermit

I dunno about your time and school and things, but you might want to wait on installing those parts if your car is currently running good. If you need it for college, is it worth the risk?

gergrx7

youll be running really rich, with 4x 720s. youll foul out plugs quickly adn will go through alot of gas. you could try to adjust the SAFC to what you think would be close but you have to be extremly careful, because you are not a professional adn dont have a wideband or anythign to go off of to tune it correctly.

gsracer

I'm going to assume you have the safc tied into the pressure sensor. On the low map set the afm correctoin to -23 percent across the entire rpm range, set the cross over at the point when you cross over into positive manifold pressure. Set the high map to cross over at 5-6 pounds and set it retardedly rich; like - 8 percent across the entire rpm range.

When you tune it on a dyno or with a wideband, feel free to move around the cross over points to whatever works out the best.

Ocelot

Well besides spark plugs, what could go wrong running a bit rich? All I needed are some S-AFC values that should put me in "about" the right area for the time being. Unless someone can tell me of any other reasons why this would be a bad idea.

Ocelot

Could you or someone else explain the reasoning behind these values? I'm not exactly sure about how the whole system works besides modifying the AFM signal. I'm a bit confused about the high/low maps so any help would be appreciated.

gsracer

You are currently using 4 x 720cc injectors. This is 2880cc's of fuel. The stock ecu still thinks you are running 4 x 550cc's or 2200cc's of fuel.

2200/2880 ~ 76.4 percent

100 - 76.4 = 23.6 or ~ 23 percent.

This is where the negative 23 percent is coming from.

The safc has a high and low map. It switches between the different maps based on the user inputted throttle (or pressure depending on how you wired it) position. If the safc is in an area that is between the low and high maps it will interpolate an average.

For more in depth information about wiring the safc via the pressure sensor look at the very first posts in the safc section.

That's about it. I would estimate you'd be running between 7 and 8 pounds depening on weather conditions. We have very similar set ups.

Silverfc88

iTrader: (7)

Damn bro thats alot of fuel. Atleast leave it a little rich and try to stay of the gas until you get there. I'm sure someone there will be able to help you out. I wish I didn't hard wire the wideband into the car or else I would've done a couple of runs with ya.

Might be a good idea later on to get a wideband so that you can keep track of your AFR's.

Good Luck in VA! Watch out for the cops out there there just as bad as here and if you get pulled over remember to pull the radar detector..

Ocelot

Stay off the gas with a new turbo/exhaust after not driving my car for about a month and going on a 8 hour trip.....damn thats asking a lot, lol

How unsafe is it running at -23% and boosting? What can go wrong besides ruining my plugs? The car isn't like 100% required to go with me, but if I don't take it with me now, i'll have to pay for a bus/train back to NJ to get it all settled. If i'm lucky, and I mean REALLY lucky i'll have the stuff installed on thursday and i'll have friday to get it dyno tuned. Friday though is when i'm leaving and I have to pack and all so it will be REALLY hard to get that done.

gsracer

Only the low map should be set to -23 percent. Hell you could set the high map to 0 and just run absolutely pig rich if you are afraid about accidentally boosting that high. I think the best course of action is what i've already described. Set the afc to -23 percent on the low map and -8 percent on the high map.

Running rich = fouling plugs and losing some fuel economy.
Running lean = new motor.

So it's a smart idea to err on the side of caution. Hah, actually I went to a group dyno the morning of my senior prom...made it back with 30 minutes to take a shower and change before going to pick up my date.

Ocelot

How unsafe would I be running -23 and -8 though? If its safe to run with those settings and boosting then i'll do it, but i'd rather not bog it down by running SUPER rich if I can avoid it.

gsracer

Yes it should be safe at 8-9 pounds, (which is the max boost I'd venture to say you'd see without some sort of boost controller)
but I don't see the point in romping on it without it tuned. This is more of a base map that will let you start, drive, and run the car; ideally to a dyno. My guess is with those settings you'd probably run rich enough to almost bog down the motor, and you might become discouraged from the lack of power (even if there is plenty of potential power to be made)

Ocelot

w00h00! Looks like I MAY be able to get my car tuned the day I leave for school if I can get the turbo installed all on thursday. I REALLY could use some luck right now, and probably coffee friday morning when i'll have to wake up at 6:30 to be able to get this all done the day before I leave for school. Hopefully my next post in this thread will be my dyno graph

Silverfc88

iTrader: (7)

What shop are you taking it to?

Ocelot

Acosta, the guys with the 950hp rx8 that were at rotorfest.