Learning to read Data.

B

btucker_ss2

New member
I am am still learning to read the data and need a little help. I am trying to understand what is going on.

I have attached some data that I collected tonight. What am I not seeing?

I know the blm is 108 which is Rich. Is my iac correct when I did my intial startup procedures I got the iac unplugged to be about 38.

Fuel pressure is 13.5 psi. Could this lead to the being Rich.

Thank you for the help.
 

Attachments

  • 20070808_203600_LOG.txt
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  • 20070808_203527_BLM.txt
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  • 20070808_203534_INT.txt
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  • 20070808_203546_O2.txt
    8.9 KB · Views: 460
  • 20070808_204439_LOG.txt
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  • 20070808_205103_BLM.txt
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  • 20070808_205109_INT.txt
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Where did you get that chip?

What system and parts are you using?

You need to check the malf box on the data logger next time.
All boxes except the raw should be on.

Also you don't need to stop the blm data unless you make a change or are done.

Fuel is way Rich and could probably be helped by turning the fp down to about 11-12psi and then log more data.

Iac is fine for now. Fuel has to be trimmed to know for sure.
 
I pulled my system from 87 GM truck with the 7747 computer.

I am using computer controlled timing and wiring harness from the afi distributor. I am only using the map sensor, aic, and coolant. The TBI has 350 injectors (orange and black). I didn't go with the knock sensors or vss. (after I learn a little might go that direction on vss)

I will adjust the fuel presure tonight and rerun the data. I might change the new coolant sensor back to the old one. I have a robertshaw thermostat (180) in the truck it seems to run about 175. I have read in some post that the ideal temp is 185 to 190.

Thanks
 
Then you should not have to make any adjustments to your fuel pressure and just send the data to them and have them burn you another chip.

That's what I was trying to find out.

I thought I recognized the chip.
 
One other thing to keep in mind is the return line can affect the pressure line.
So hook your gauge to the pressure line and see what it is...
Then remove the return from the tb and just run a hose straight to a bucket or gas can.
Then check the pressure again.

If the pressure drops then there is a restriction in the return.

I would not call 13.5 outside of a factory setting. There is a +- to the factory pressure.
But it is on the high side of what I have measured.

If the chip was already on the Rich side and then you have more pressure..it just makes things worse.
 
I have a gauge on the return line. The return line is 5/16 line. I will check the pressure again but the last time I looked the pressure was 0-1 psi. I have been running the same lines with the old Holley projection and never had anything greater than 1 psi on the return.

I will look. I will be changing the fuel pressure spring this afternoon with another TBI spring. I will let you know what happens.
 
Do you have any idea why the pressure won't adjust down?
You should be turning the bottom clockwise like you are tightening it. That will cause the plunger to move down and reduce the spring pressure.

If the tab is at the top of the slot then that is max pressure.


Btw-I run 180° in all of mine.
 
Do you have any idea why the pressure won't adjust down?

I have taken the fuel pressure regulator apart and double checked that it was turned all the way down. The tab is on the bottom of the slot.

The fuel pressure for the return line is below 1 psi. I did the bucket trick requested and double checked that with the gauge hooked into return line to the tank. No change. This is also with a new gauge.
How hard will it be to change the fuel curves with a programmer? I am still trying to figure out the conversion of blm to bin. I downloaded the program off the binder but I must still be doing something wrong to make it work
 
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The only pressure you have mentioned is 13.5psi.
So I'm assuming that's what you are reading no matter where you adjust the tab to on the regulator.

If so then the only things I can think of that would affect it is the diaphram, the spring, something in one of the fuel passages in the injector pod.

But I would think that the pressure would vary as you reved it up if that was the problem.

Adjusting the fuel table is not difficult.

The idividual cells of the blm table go from 0-256.
So 128 is the middle. This is stoick or 14.7 afr.

If it reads lower then that..say 120, then the fuel is too Rich and you need to subtract from the number in the fuel table.
If it reads high like 140, then you are lean and you need to add to the number in the fuel table.

The program you use to adjust the fuel table will determine how you add or subtract from the table.
 
If I move the tab up the pressure goes up. The fuel pressure is not moving around. It is rock solid. When I put a load on the truck it May move from 13.5 to 13.1 but that is hard to see. I really don't trust myself trying to drive and hang onto the hood.:gringrin:

I have a chip burner and I am trying to learn how to use it. I have been looking at the cats and tunpro. To make these programs work dont need to convert blm to bin?

This is what I am having problems with.
 
So, you are saying the regulator will adjust the pressure, it just won't go down below the 13psi.

That's fine, just make the adjustments from there.

Tell me what program your going to use and what burner and chip you have and I can help you make the adjustments.
 
I like the cats tuner. Or this is the one I am looking at for now. If you think I should use another program please let me know.

I have a dual power willem universal eprom programmer dual and the software that came with it. I will be using a stock GM chip. 2732 chip (?)

overall I have been learning alot and would like to thank you for the help.

13.5 psi is as low as I can get it. I can raise it to 15 psi without a problem but that doesn't help.

Bt
 
You May be on your own for the willem.
I bought one and could not get it to program the 2732 properly.
So if you have one, make sure you read your current chip and save the file.
Then try to program a different chip with the same file and see if it works the same with no errors when running.
Have you tried to program a chip yet?

Cats is fairly easy and has nice graphs.

Let me know when your sure you can program a chip.
If you can read the current chip and post it up here with the blm data, I can show you how to ruff it in.
 
I have a modified willem (not overseas made). You need to have high voltage and current to program 2732s. My willem has been modifed with power relays and uses a separate power supply and can program all kinds of chips. The ones made overseas and sell for $20-30 won't work


also there is a difference in programing voltage for 2732 and 2732a. However they both work in the 7747 ECM.
 
2732b(12.7v vpp),
2732a(21v vpp),
2732(25v vpp),

there is also a 2732g at 12.5v

and the raised window 2732 I run at 25v
 
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