http://www.angelfire.com/art2/tkd91rs/DSCF0003.JPG

theres my dyno graph

im gettign lean after 3800rpm then my power drops off. how can i make it richer up there. with winaldl it shows that most of my cells are rich. some are even in the 90's. ive tried to lower the numbers in the main fuel table #1. but it doesn' t seem to be working very well. should i lower the bpw/injector constant, its at 136 right now, and i have 65lb injectors at like 14-15psi. or do i now look at the main table #2. i think i read that people would change all their numbers to 0 in the first table and just use the second one.

 

Link to the graph didn't work.

 

I would turn the fuel pressure up 4-5 psi and make another pass on the dyno to see where things are.

If you lower the BPW that will just lean it out at WOT which you don't want. I'd leave the BPW alone for now. Increasing the BPW may result in the injectors running too high a Duty Cycle which will probably cause WOT fueling trouble.

The WOT A/F Ratio is limited by the injector size and fuel pressure. If you don't have enough pressure, nothing you do in the prom will make things richer.

As far as part throttle and BLMs go, a ten percent cut in the light load areas of the fuel map should be noticable in the INT and BLM.


Do you have a WINALDL recording of the Dyno runs? Would you post it?

 

its working. i just clicked on it.

no i didn't have winaldl on during the dyno.

but i increased my fuel pressure for the last run liek 4 psi more, and it ran like ****. started jumping on the dyno and my numbers were way less and sparatic.

 

here it is

 

my numbers are really rich when im using Winaldl. some are in the 90's. but at WOT the graph shows the fuel. so do i need to lean out all my cruising speeds, and richen up in WOT after 3800rpms

 

My thoughts...

I am going to talk about dyno run #1 ... the RED curve.

1) You need more acceleration enrichment. You are lean up to about 2200-2300rpms ... at which point it appears to cross the 13:1 barrier.
2) Starting somewhere around 2800rpms you are too rich. The AFR appears to be around 12:1 in this area which, IMHO, is too rich for maximum power on a NA motor with a setup like yours.
3) You're running rich from 2800 all the way till about 4100rpms. I don't know why you want to richen it up everywhere after 3800 since at 4100 it still appears to be rich (~12:1).
4) 4300rpms APPEARS to be on-the-money if you are shooting for a good AFR.
5) I would only richen it up from 4400 or 4500 and then greater.
6) I REALLY don't see a lean problem except for the pump in the beginning and the very end of the curve.

More data and a better picture would be helpful and could nullify my statements above. It's really hard to read that picture.

Tim

 

Post your current bin file or e-mail it to me and I'll tell you what's going on and how to make that better.
It's all in the tuning of the chip, which I can comment on since the code you're running is the same as mine.

 

ill email u my bin file and dyno sheet. and lastest winaldl file

 

Without knowing what your injector Pulse Widths are, your just going to be guessing at what your doing.
Logging a pass and seeing what your PWs or DC's are, would be extremely meaningful.

Once you do that then you can either just boost the PE vs RPM table, or you'll have to adjust your fuel pressure. Adjusting the fuel pressure means reworking the MAF tables, to clean up the lower end, since changing the FP is a universal change and all you really want to do is increase the WOT fuel.

And there maybe mechanical reasons for the leaness up on top.

 

does winaldl log pw and dc's.

 

It can, just depends on what code you're running in the eprom.
I'm going to type up a tech article specifically for the 8746 and the eprom ALDL output. Even though I haven't the need for winaldl anymore (lockers) it's still a great tool, better than nothing.

 

better view of my dyno sheet


http://home.comcast.net/~tkd89rs/DYNO.JPG

 

After looking at the better pic you posted I'm gonna change my tune. haha I thought the A/F ratio looked like it was in the 14's in the previous pic.

Anyhow, looks like you are relatively safe with the fuel pressure you've got. Unless your injector duty cycle is maxed out.

 

doesnt a catalytic converter make your fuel mixture at the tailpipe read leaner than if you did not have one? If i recall correctly, Ive read that it generally makes for afrs 1 point leaner than actual, in which case, he would be going somewhat lean at 4200 rpm or so

 

Mr. Prevost or anyone?
what is the optimal Air/ Fuel at all RPMS in PE?
My dyno run showed any where from 12.2 to 11.9 above 3500 rpms. cant recall what is was below 3500 rpms but i think was leaner. will need to look over dyno sheet . this is a non emmisions engine. dyno operator suggested 12.0 too lean. Suggested 11.5 is where i should be. this is a very general statement i changed prom in PE to enrichen but did not go back on dyno. now my heads are as were edel alum RPM 64 cc BUT they are 2003 edition not prior flavor. more effecient supposedly (CNC)? can a better head design (fast burn) run leaner? does fact of non emmisions (no cat, no egr, no air pump) allow me to run leaner or richer? see Pablo comments.

 

Best AFR varies by engine.
I run 11.8ish but that's on a turbo motor.

Run richer then Stoich, and the excess fuel is just used for in cylinder temperature control. So motors need alot of in cylinder cooking to make high HP. Some don't. My BBC truck runs well at 13:1.

fast burn is primarily about how much timing you need to run.

Cats require excessively rich mixtures to work, and live at WOT.
EGR when on, needs an excess of fuel to have a burnable mixture.
Air pump is external to the engine and has nothing to do with what AFRs are needed.

 

I think these are back to front. The cat converts CO to CO2 for instance, and that means O2 is consumed in the cat, not generated.

The O2S measures oxygen content at the point of the sensor. It therefore seems to me that you're going to read richer after the cat than the motor is seeing.

John

 

ah, makes sense

 

Did u get my email jon

 

so how exactly would i go about changing my fuel. which tables should i change. and im running really rich according to winaldl. soem of the cells are 90-110. and ive tried to lower it in the first fuel table. so should i lower my BPW's.

 

i read the BPW should not be changed to account for rich BLM's. I had my table #1 down to 1.0 at 20 map and needed leaner. so i reduced the table 2 at rpms where rich at 20 map(1200-2400 rpm). that threw off the 30-100 map so i needed to readjust those richer. BPW has a calculation for engine size/ CID/ and fuel pressure. set it and forget it? maybe someone can comment on when it is appropriate to tune by changing BPW.

 

ive heard of people jus changing there first fuel table to all zeros. and only use the second one. is this better than what im doin. i dont think ive touched the second table yet.

 

how do i get winaldl to show me PW's and DC's

 

anyone

 

here is a link to RBob explaining how to see the PW on the 747 and 746 ecu's.

https://www.thirdgen.org/techbb2/sho...hreadid=210908

 

See this thread over on the TBI board. Just be sure to get the post for your ECM. There is one for the '747 & another for the '8746. The DC you will need to calculate from the RPM & the PW.

https://www.thirdgen.org/techbb2/sho...hreadid=210908

RBob.