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do I need a tune if...

Old 09-21-2018, 09:27 PM
  #41  
clove86
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Ok I got the 24lbs injectors installed and the car runs great. Working on data logs for a tune.

My question is, what do I do with the old multecs?
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Old 09-21-2018, 11:13 PM
  #42  
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Originally Posted by clove86 View Post
Ok I got the 24lbs injectors installed and the car runs great. Working on data logs for a tune.

My question is, what do I do with the old multecs?
Do you feel it is morally wrong to sell someone a set of injectors you don't think (assuming you don't) is good for much besides target practice? I suppose if you want to keep it looking 100% stock and I have a set, well....
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Old 09-22-2018, 09:21 PM
  #43  
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I wanted to know what the general consensus was.
I don't know what to do.
They ran great for being so old.
I've seen where some were rebuilt. But whatever I can throw them out
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Old 09-22-2018, 09:39 PM
  #44  
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Originally Posted by clove86 View Post
I wanted to know what the general consensus was.
I don't know what to do.
They ran great for being so old.
I've seen where some were rebuilt. But whatever I can throw them out
You can clean the injector and whatever but if ethanol runs into it the coils could be damaged. If you can always use pure gas, sure. OTOH, I don't like be tied to a few gas stations only so why would I want that injector? Now if someone has to be as close to original as possible, I suppose.
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Old 09-25-2018, 05:47 PM
  #45  
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Originally Posted by aklim View Post
Probably wouldn't run perfect. I'd wait till I have headers and just do a dyno tune. Depends on how finicky you are. If you are like me, I'd do it all at once, get the tune and go with it. I'd find the facility to dyno tune instead of "guess a tune" unless they do fine tune with datalogs.
I did 24lb injectors and the car was not as fast , after the guy who made the tune adjusted the injection to spray like 22lb injectors , the car picked up power again! 24 is too rich
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Old 09-25-2018, 09:58 PM
  #46  
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The dual fire was thought to work well at low rpms by putting a "fresh" shot of fuel into more of the cylinders. By this I mean having the injectors spray on an open valve. About 10 years ago I began playing with the older MegaSquirt 1 system. It was good for batch fire and a distributor or coil pack. With it I experimented with changing injector timing and even doing the dual pulse, none of which changed the power output or fuel usage on my firebird. The reason for this is your valve is open for roughly 25% of the engine cycle(2 crank rotations) when your duty cycle is over 25% you are spraying on a closed valve.

Injector timing has the biggest impact on sequential cars up to cruising speed. Past that it's kinda a waist. I have experimented with the 60* v6 and the LT1 on the megasquirt platform and unfortunately there are only 2 ways to get more fuel, bigger injectors and higher pressure. And a fun fact flow does not increase linearly with pressure, the rate if pressure increase is inversely proportional to the flow rate.
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Old 09-25-2018, 10:48 PM
  #47  
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Originally Posted by aguilar92c4 View Post
I did 24lb injectors and the car was not as fast , after the guy who made the tune adjusted the injection to spray like 22lb injectors , the car picked up power again! 24 is too rich
How do you figure? To make a 24 spray like a 22, doesn't that mean he has to reprogram the ECM to 22pph specs? IOW, it should have more pulse width to spray the same volume. If you make 5 passes with a 5 gallon bucket, you have more water than 5 passes with a 1 gallon bucket.
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Old 09-27-2018, 07:36 PM
  #48  
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I have 1991 speed density tpi.
I'm trying to data log with tunerpro. I continuously get da error and corrupted data results.
This seems to be common with 90-91 cars.
Does anyone have a fix. I can't find it.
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Old 09-27-2018, 08:30 PM
  #49  
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Use this ADX.
90 corvette adx

I use that, I had my 90 out today data logging and it works perfect
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Old 09-27-2018, 09:28 PM
  #50  
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Thx I'll give it a try
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Old 09-28-2018, 10:50 PM
  #51  
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OMG 49 emails on a no nothing change...a swap nevertheless. Which is an all ok change.

NO YOU DO NOT NEED TUNE AS YOU'VE ACCOMPLISHED 2HP GAIN.

MIC DROP
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Old 10-10-2018, 08:32 PM
  #52  
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so I have a moates usb aldl cable and I am trying to use tunerpro.
I am recording data logs and now a major problem I am having is the loop status fluctuates between open and closed while driving.
I now this is not normal. what I don't know is if the car is actually sending an accurate signal, or, a problem within tunerpro.
has anyone ever had experience with this issue?
what can I do?

O2 sensor is new.

Can someone look the attached datalog and give some insight to the o2 readings?
Attached Files
File Type: zip
test.zip (52.5 KB, 3 views)

Last edited by clove86; 10-12-2018 at 02:34 PM.
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Old 10-14-2018, 12:43 PM
  #53  
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Bump...

Why won't the car go into closed loop?
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Old Yesterday, 02:13 PM
  #54  
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Have you tried a 3 wire heated o2 ?
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Old Yesterday, 07:48 PM
  #55  
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I've looked into it
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