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somebody look at the air/fuel graph on this map and point me in the right direction. performance seems good over 3000 rpm.
 

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2005 Road King Classic
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jnbernstein said:
somebody look at the air/fuel graph on this map and point me in the right direction. performance seems good over 3000 rpm.
You would be better off having those as pdf file. I couldn't open them.
 

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The AFR Table is just used as a target value, it really does not affect AFR. Real AFR changes are made in the VE tables(front & rear). The only way to do that is with a realtime AFR gauge and you need to do each cylinder separately. Best done on a dyno.
 

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Discussion Starter · #5 ·
Totenkopf said:
The AFR Table is just used as a target value, it really does not affect AFR. Real AFR changes are made in the VE tables(front & rear). The only way to do that is with a realtime AFR gauge and you need to do each cylinder separately. Best done on a dyno.

lsr 2/1 blackhole can't be done on a dyno so rb racing says
 

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jnbernstein said:
lsr 2/1 blackhole can't be done on a dyno so rb racing says
jnbernstein and I discussed this offline and the answer is that it can be done through the O2 bungs. He's waiting for RB to send the rear primary tube with the bung welded in. Apparently the Black Hole has some baffling in the muffler that doesn't allow the normal "up the butt" AFR sniffer placement, that's okay, just sniff from the bungs.
 

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Totenkopf said:
The AFR Table is just used as a target value, it really does not affect AFR. Real AFR changes are made in the VE tables(front & rear). The only way to do that is with a realtime AFR gauge and you need to do each cylinder separately. Best done on a dyno.
Can you explain? So what is the purpose of this table?
 

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Doing time, behind bars!
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Got to think about that some more............

Totenkopf said:
The AFR Table is just used as a target value, it really does not affect AFR. Real AFR changes are made in the VE tables(front & rear). The only way to do that is with a realtime AFR gauge and you need to do each cylinder separately. Best done on a dyno.
OK, follow that line of reason, why are we able to change the target values in the AFR table?

I know that they will not represent the actually AFR, but the ECM uses these numbers as a target, therefore does it's calculation (how much fuel to squirt & when to spark) from that number (and others) and IF the numbers are different, then the calcution (how much fuel to squirt & when to spark) must be different, yes? So, it may squirt more or less fuel which would affect the AFR, no?

I'm no expert, only what I read and understand from the manual, and most of the time I'm like this ----> :huh:
 

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The_Snowman said:
OK, follow that line of reason, why are we able to change the target values in the AFR table?

I know that they will not represent the actually AFR, but the ECM uses these numbers as a target, therefore does it's calculation (how much fuel to squirt & when to spark) from that number (and others) and IF the numbers are different, then the calcution (how much fuel to squirt & when to spark) must be different, yes? So, it may squirt more or less fuel which would affect the AFR, no?

I'm no expert, only what I read and understand from the manual, and most of the time I'm like this ----> :huh:
From the experimenting I've done, I don't see any difference in measured AFR by changing the AFR table numbers. Now, make changes in the VE tables and that DOES directly affect measured AFR. When you Data Log record, you can see the Desired AFR displayed from the AFR table, you can rail its value and it does nothing that I've seen. Go figure?! Now, because we don't know exactly what's going on behind the curtain, I plug in AFR values that I would like to see into the table but during a real tune session, it's all done with VE tables and Spark Advance tables.
 

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NCR52 said:
Can you explain? So what is the purpose of this table?
From Steve Cole:

The Delphi EFI system is a speed density type system. You need to tell it what the VE is in each cylinder so it can calculate the predicted AFR. So if the VE is wrong so will the AFR. The way I tune is to start by setting all the AFR cells to 13:1. I then adjust the VE tables so I get 13:1. Now the system is properly calibrated. Now drop the orginal AFR table back in and were almost done. Just change the AFR table for best power while keeping an eye on the exhaust gas temperature. I do have a dyno and real time AFR equipment.

So what this means is the VE is the base used for the fuel calculations. Moving it causes all the fuel tables to move right with it. So by raiseing the VE numbers you are telling the ECM there is more air present in the cylinder. Hope this helps you understand it some.
The VE table tells the ecm how much air is entering the cylinder. It then uses this to calculate the amount of fuel needed to reach the desired AFR. So you can change either the AFR of the VE's to change fuel mixture. By making the VE's correct the desired AFR table will give you the correct mixture. With the VE's incorrect the Desired AFR will also be incorrect. An example would be if the VE's were off by 10% the desired AFR would also be off by 10%. so you might show a desired AFR of 13.8 : 1 in the RT but your really only getting 14.2 :1. Another way to change fuel mixture globally would be to change the fuel injector size or cylinder volume. I use this as a quick check only when tuning. If I think it needs to be richer everywhere I change injector size down and see if I get the desired results. If I do then it back to the original size and change the VE's by the same percentage as I did the injector size. The RT will let you do just about anything you could need to do on your bike.
:yes:
 

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my observations............

From what I'm seeing, you tell the race tuner the engine displacement, the injector size in gms/sec, which are then held as Constants(by the way, they are a great way to get more range out of the SERT, if you need it). Then volumetric efficiency percentages are input for different throttle positions and engine rpms, which is a way of combining cylinder size, cam, pipe flow and head flow, the software then has enough information to tell the injectors the pulse width in millisec's to get the right amount of fuel in for the available O2 at any given moment. I have not seen AFR table changes change the measured AFR, as far as I can tell, it only appears to be a "marker". But then again, I've not measured EGT, only AFR.

Anyone else know if the AFR table actually, DIRECTLY, does anything that is measureable?
 

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Thanks WVRDKING,
I must have missed this in the SERT manual. I will have to think this one through as to why my dealer made the changes to the AFR Table and VE tables to cure the Cold Start Issue vs adjusting the Warmup Enrichment and the IAC Warmup Steps.

How do these two tables interface with the AFR Table? Just when I thought I was starting to understand this...
 

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Fuel SYS ENG
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Steve is pretty much spot on with his analogy. Some of the things he's metioned are tricks we use in the car tuning world and work very well. If you have one of the newer bikes with a narrow O2 sensor (closed loop system) then your O2 sensor will keep the command AFR at 14.7 stoich.

The warm-up enrichment and IAC valve table work together to enable the ECU to add a little more air/fuel until the engine warms up (just like a manual choke on a carb). Adding a little more timing in this area will help the bike warm-up a little quicker too!

Cheers,
Frank{salute(
 

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Vetteman said:
The warm-up enrichment and IAC valve table work together to enable the ECU to add a little more air/fuel until the engine warms up (just like a manual choke on a carb). Adding a little more timing in this area will help the bike warm-up a little quicker too!

Cheers,
Frank{salute(
Frank,
Can provide suggestions on the settings or enrichment values and timing for this?

Oh yes, I found the section in the manual that makes reference in pages 113 thru 116. However, it talks about resetting he AFR table to the original settings (set reference) after you have optimized your settings in the VE tables.

Thanks
 

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Fuel SYS ENG
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All is well. Just signed a lease for the shop. Dyno's will be delivered on Monday. I have lots to do to get the building the way I want it. Are you in your shop yet?

Cheers,
Frank{salute(
 
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