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Discussion Starter #1 (Edited)
When I bought the car, I noticed it has 2 external 440cc's on the hardpipes. Also there's a unit (MF2, which supposedly controls the injectors) in the ECU area on the passenger's footrest.

It never bothered me before that the injectors aren't on because the MF2 was disconnected (there's a harness that runs from the injectors to the MF2). So I figured that the injectors aren't on because the MF2 isn't connected.

So anyways, I connected the MF2 today thinking that the injectors would come on. Nothing happened. I checked by unscrewing the injectors out and seeing if any fuel is coming out. There's no fuel coming out.

Any ideas? I believe SoAngel can ring in on this?

You can see the injectors right here:
 

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Discussion Starter #3
rwsupra.com said:
I believe they only come on at a certain boost or RPM....

Yea I'm talking to Dave H and he says they only come on under boost. I guess I'll wait till my pop gets home or someone and have them rev the car and I'll see if fuel comes out. I have a 2-step so that should help build boost in idle.

So let's say I have 460cc's in the main rails, and the (2) 440cc's externally. When the (2) 440cc's come online, it should be the equivalent of ~600cc's.

So... when I tune it, should I assume that it's still 460cc's and only ~600cc's under boost? So if I run a tt MAF (550cc's) I should richen up when the external injectors are not online and lean out when they are?

-------

Yea this external injectors shit is stupid. I know the easier way is to just get 6 bigger railed ones. But right now, since I have the 2 external ones, might as well get them to work, which is cheaper.
 

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Discussion Starter #4
Anyways, I was thinking of deleting this thread, but it might help anyone out in the future so I won't.

Anyways, since I have a 2-step it can build boost in neutral. I took off the injector and rubberbanded a piece if paper to the tip (if fuel comes out the paper will be wet). I then revved the engine without the 2-step on, no fuel came out. Then I turned on the 2-step and built about 8psi of boost, fuel came out. The paper only got minorly soaked, but I guess at least fuel came out.

So anyways, I guess it only comes out on boost. I guess this means it'll be a bitch to tune since it doesn't flow the same fuel all the time. It'll also be a bitch to tune since I won't wot the car all the time so the SAFC settings will be diff and fun to play with.
 

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TT This
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Whats your hp goal? Will the 460's in the rail be good enough for your hp/fuel needs?, and say screw the 2 440's for now(disconnect em)? :dunno:
easier on the tuning perhaps
 

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Discussion Starter #6
NinetyFiveNA said:
Whats your hp goal? Will the 460's in the rail be good enough for your hp/fuel needs?, and say screw the 2 440's for now(disconnect em)? :dunno:
easier on the tuning perhaps
I don't really know what injectors are on the rail. I can only assume they are ~440-460cc's since they are prob not 550's and 440/460 seem to be the only other choices.

I tuned the injectors (with the external ones off) and only got [email protected] So I'm not sure what's up.

Here's my settings on stock MAF if anyone can make an educated guess as to what injectors I have: Between 1500-4000 we just BSed the setting. It wasn't tuned until it reaches above 4000rpm.
1500 = -10
2000 = -23
2500 = -23
3000 = -23
3500 = -23
4000 = -33
4500 = -40
5000 = -38
5500 = -40
6000 = -32
6500 = -35

 

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michaelvanle said:
So anyways, I guess it only comes out on boost. I guess this means it'll be a bitch to tune since it doesn't flow the same fuel all the time. It'll also be a bitch to tune since I won't wot the car all the time so the SAFC settings will be diff and fun to play with.
Ouch, yeah sounds like it will be tough to tune.
what about selling the 2 440's and MF2, and pluggin the injector holes
and getting 525's
I'm sure when you sell the two 440's, the MF2, and the 6 460's. You'll be pretty even in terms of spending.....
just an idea :dunno:
 

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Discussion Starter #8
kmn5 said:
Ouch, yeah sounds like it will be tough to tune.
what about selling the 2 440's and MF2, and pluggin the injector holes
and getting 525's
I'm sure when you sell the two 440's, the MF2, and the 6 460's. You'll be pretty even in terms of spending.....
just an idea :dunno:
Haven't ever changed injectors before, and removing the Y manifold looks like a bitch. But that might be an option soon. I'm just still trying to squeeze out the 2 external injectors to see if it works :/
 

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Actually when I had that setup with my small 60 trim turbo it was pretty easy to tune. I just ran out of fuel around 411rwhp with the 8 440cc, so I had to get an fpr. After that I just sold that setup because I didn’t like the fact that fuel was in my intercooler piping.
 

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Discussion Starter #10
neostreamsupra said:
Actually when I had that setup with my small 60 trim turbo it was pretty easy to tune. I just ran out of fuel around 411rwhp with the 8 440cc, so I had to get an fpr. After that I just sold that setup because I didn’t like the fact that fuel was in my intercooler piping.

Oh was it? Well I guess the (2) injectors only come on under wot, so I'll have to tune it for wot. But then if I'm not under wot, the settings might make the car run rich.

We'll see I guess. Thanks for the comment.
 
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