I ran my car at the track. It felt so good on the street. Ran terrible at the track. I added a ton of fuel at WOT, and my MPH stood exactly the same...? Is this the right table to adjust? I know you need a wideband to tune. But after 4700 RPM, my O2 sensor went way down to like 300 volts. By the way, it's 32B mask.

Looks to be the correct table. IIRC, there is an adjustment based on CTS, and the one shown based on RPM. It is a percentage difference from the stoich value.

The only part I'm not sure about is the PW tables. In the $32/$32B code the ECM fueling can be run from injector PW tables. In this case I don't know if the PE AFR is actually used or not.

OK, a quick look at the code and it appears that it is used. If the injector PW tables are in use the commanded AFR is still used in the PW calculation.

RBob.

Thanks for the reply. So is using this table the incorrect way to add fuel at WOT?

That table looks to be the same as PE mode tables in 6E. You can use that to dial in air fuel and also I do believe you can use the open loop AFR % change vs Load to change fuel.

The other way that may work even better is to adjust BPW vs load table. You can precisely target the RPM and the Load LV8 value while the PE mode adder just globally changes air fuel for that rpm range regardless of LV8 as long as you are in PE mode. Typically first gear will have less load on the motor than second and third. With the big gear ratio drop between 1st and 2nd gear, I see the biggest load increase. So at 4000 rpm you may see 208 LV8 in first but in 2nd, you may see 230 there and it will change air fuel ratio.

The BPW table can correct for that.

I guess you can do it either way to get at the air fuel ratio for best power. I dont know which one is best, but I'd be tempted to try to dial in BPW first.

Wow, I added a TON of fuel there, and it did nothing to my mph.

Full Exhaust L98 with 2.77's = 14.0@98

L98 with AFR 195 heads, Comp cam (224/230, Intake .535 in/ Exhaust .544 in, 110LSA), HSR intake, Moser 12 bolt with 3.73's = 13.5@105Mph.


Soooooooooo sad! I still have the stock stall and it is killing my launch. I was launching off idle, getting traction, and pulling 2.2's. I stalled it up, launched, got traction, and still only pulled a 2.08. The launch can be fixed with a correct stall. But in my opinion, my MPH STINKS! I also added and reduced timing, no MPH change at all. The car feels strong on the street. Thought it would do way better.

In the end, I gained 7 mph, but I still don't think it's very good.

take it to a dyno and/or get a wideband o2 sensor to confirm whats goin on.

If my WOT AFR is off, do you thinks that's enough to gain like 5mph? lol. It pulls hard all the way to 6000 rpm. Here's a quick vid: http://www.youtube.com/watch?v=KXk0aDfbLmY I'm really kind of disgusted with this car. I have barely touched it. It's a shame, it runs so great and is problem free. I was going to build a engine for it this winter but I bought a crotch rocket instead. So I'm stuck with this L98 for a little while.

If I wanted to run fast at the track, I guess I should have taken the bike!

It doesn't sound right. Almost like it is rich at lower RPM and leans out up top. And the spark timing isn't right, maybe not enough?

I'd get a fuel pressure gauge or transducer on it and check that the fuel pressure holds throughout the RPM range. Get the fueling better, then move on to spark timing.

RBob.

Thanks for the reply. I have my WOT timing at 34 degrees. Starting at 3000 rpm. I bumped it up to 35, and there was no increase in MPH at all.

I have a Walbro GSS340M 255L/Hr Fuel Pump along with a Racetronix Hot Wire Upgrade Harness. I do have a FP gauge though, can't hurt to test it.

Do you run closed loop with stock narrow band o2 sensor still in the exhaust?

Do a WOT run and log the o2 milivolts and report what happens. Motor has to be warmed up and the o2 ready.

Yes I do. Here's a graph I made from a while ago.




I added a bunch of fuel at 5000rpm + at the track and there was no increase or decrease in mph. I was surprised.

That graph certainly confirms what I posted about how the engine is running. Rich then going lean up top.

Check the data log for PE mode. Make sure that the ECM is staying in PE mode throughout the run. The MAF code will at times sense a TPS voltage that it thinks is too high. At which time it will drop out of PE mode.

If that is happening it will also explain why adding fuel via the PE vs. RPM table didn't do anything.

RBob.

A few years ago, I found a similar situation. The stock fuel pump just did not have the volume to keep up. I had it on a dyno with a FP pressure gauge hooked up. the wide band went lean and the FP went down above 35oo RPM. Easy fix on my car.

How does one tell if it is staying in PE mode? All the way through the WOT run, my BLM's are at 128 and do not change. Is that how I know it is in PE Mode?

The TPS voltage all through the run is 4.29.


Thanks for the help guys!



The car has a new walbro high flow fuel pump.

Run one of your logs on the play back feature. Look at the AlDL Flags and there should be a PE mode active or not active bit. It probably goes 1 for active and 0 for inactive. Watch it throughout the run, especially around that 5000 rpm mark.

what Lb injectors do you have
where did you set your base timing
AFPR ???

I can send you my settings

from a 2nd gear Launch only @ 2.5K i was pulling 112.53
you should be in this range

I went through the flags in Datamaster, none said anything about PE at all?




Ford 30 Lb's
Base timing is at the stock 6 degrees
Yes, AFPR set at 43.5

I'd like to see your settings. Somethings not right here.

Check if the commanded AFR is displayed. It should be below 14.7 when in PE mode. If you see it returning to 14.7 then it is dropping out of PE.

Should also be able to see the richer commanded AFR when you changed the WOT AFR percent change table.

Really need to check the fuel pressure first. Filter could be clogged or the hose between the pump and feed tube in the tank could have split.

RBob.

Do you not use tunerpro rt to log? I'm not familar with datamaster.

Dont feel bad man...im in the same boat..my car went from running AWESOME, to terrible with the HSR...i dont have AFR's though, just some vortecs.

It's staying in PE mode. It never returns to 14.7 for the whole WOT run. I just changed the pump/filter 2 months ago. Everything looked fine. But it's definitely worth looking into.

I never had much luck with tuner pro. I've always used datamaster.

When you say added a ton of fuel in that table, how much did you actually add? It takes a good 15% adder to see a AFR change, atleast in my experience in tuning my setup as well as another MAF setup.

Keep trying to see if you cant get 5000 and above to show changes in the o2 milivolts. Take a little out in the mid low range to lean out your setup to around 890-900 milivolts.

6 deg is 70% of the problem
this HSR starts to come Alive @ 10 Deg
I then set it to 14 Deg Unbelievable Difference

its not about base timing, its about timing in the bin table. Doesnt matter if you set it to 6 or 20 base, base doesnt matter. Its just one parameter that gets added to many to set final timing seen at the distributor.

The timing being run at WOT in the timing table is what really matters.

Sorry I can tell you for a fact it's the timing
PS look up the HSR dyno runs!!!!! they will also tell you the same results I have
you keep handing out advice and your running Two turbos
we are NA

IROCThe5.7L.... has a very similar setup as mine I explained I left the hole from 2nd gear
and only @ 2.5K <<< why would I have 7.5 MPH more even dogging it like this ????


http://www.gmhightechperformance.com...roc/index.html

I really appreciate all the input guys!


Here is a picture of how much fuel I added. Maybe it wasn't enough? I'm still going to look into everyone's suggestions.

Where the chip was:


How much fuel I added at 5000 + rpm:



For the heck of it, here's my timing table. I have no spark being added when in PE mode:

your timing table is way to high @ almost every RPM and load
I'm pretty positive the fuel to afr is backwards

Really? I don't get any knock retard or pinging. I always read 34-36 degrees of WOT timing is the sweet spot for AFR'S. The chip is from Ed Wright that I'm building off of. But the timing table for the most part is his with some minor tweaking from me.


Does this table have a large effect on AFR?

[quote=88gta3508;4666817] you keep handing out advice and your running Two turbos we are NA
/QUOTE]

I don't think that is a fair statement...
Orr may have twin turbos now, but I appears to me that he's tuned some very strong running Normally Aspirated cars as well.

You forget I had an HSR bolt on L98 that went 12.95 bolt ons only, and my old 383 HSR motor at went 11.4s in the heat, 10.6's on spray, and a heads cam 360" HSR motor that should be mid 12's easily once we tune it up. My buddy has a 406 he tunes that runs mid 10s on motor and I've seen the tune for it. My tune for my 383 was used in another 385 superam car. I've seen another 383 HSR tune that also goes 11's. None of these cars run base timing over 10-12 deg. Most are between 8 and 10.

With stock L98 timing table, my L98 car ran best with 8 deg base timing over 6 stock...thats with no changes to the main table and stock bin still showing reference angle of 6 deg. Guess what happens when I set bin to 8 deg reference angle and then added 2 deg to entire spark table? Ran the exact same.

Same applies to tuning my turbos. Base timing is set then forget. Match it in the bin and work your timing for idle and all operating cells thru the main table.

http://www.thirdgen.org/techboard/di...cs-anyone.html (Timing Logics anyone ?)

Read that...similar logic is used in the other ecms for these cars. Got to read the arap MAF hack but i believe its the same.
Main spark table contain the values you want to see at the crank. Base/intial timing you've mentioned is subtracted out of the main table but its added later by the distributor anyway because its a mechanical advance. So thats why the base timing in the bin needs to match the motor base timing or else the wrong value is subtracted and you will see different spark at the motor.

There is a max spark advance cap in the bin that limits what can be programmed into the distributor. Most bins have 42 as max advance allowed, so the value the distributor can add is 42 deg. Plug terminals are only 45 deg apart So the chip sets it at 42 or else you can end up having spark go to other cylinders. It will be firing at another plug terminal before it reaches the actual terminal its trying to fire.

Your logs may show only 42 for some points where you may want to see 48 deg in the main table, but thats because the distributor can only add 42 deg based on design limitations. ECM will send command of 48 deg to distributor but before it gets there, it is checked against the max spark value of 42. If its greater, then its capped at 42. 42 is sent to dizzy, and the base timing is added to that to make 48 at the crank.

Base timing is used at startup and less makes it easier to start. Thats why I like to set my timing to something as low as the motor will handle. My 383 would not idle on its own with 6 deg, but barely idled with 10 so i left it at 10 base.



Yes that AFR WOT table should have an effect on the fueling but you will need to add alot more than you did. Those o2 milivolts are very low, i'd add 20-30% there above 4800 and try again to see what the volts do. Dont stay in it too long, dont want to burn up a piston if its really that lean. Keep adding in 20% til you start to see near 900 milivolts. You need to see if a big change really changes the way the car feels.


Your timing able looks fine as long as no PE mode spark advance is being added. If anything its alittle conservative in a few spots. 140-176 LV8 and higher rpms is abit low. Table should rise from full load to low load. you could carry the values in column 128 and above 2200 rpm all the way over to 196 LV8 column. Idle advance is aggressive which is good with that cam.

Ed is pretty good with tuning so his table is pretty good. WOT looks fine. Just add fuel and I think you will be REALLY happy how it pulls

Yes really!!!
were going to start a battle I'm sure >>> EW <<< I would not let him tune
my RC car!!!! years back.. I had a built 350 TPI.. running rich...
a friend recommends EW I gave him a print out of my scan plus a complete parts list of installed parts.. I received his tune cleared the AFR.. but could not rev in neutral above 1/4 throttle.. I called and explained this Issue..
I receive a 2nd tune same results only i could rev slightly above 1/4 throttle
WHAT A RIP OFF... I started programming after his first tune.. his 2nd TUNE I discovered a slightly tweaked stock TPI 350 Vette base... I still have the chip
It should be worth 1,000's now.... it's his only bad one RIGHT I have herd MANY people got screwed as well!!!!!!!

[quote=GTA Sammy;4667005]and yes I know.. ORR is a pretty smart fellow!!!!
But the fact is all of the Dyno's I have looked at all show the timing must be adv
for the HSR... that's why I tried it And sure enough it worked as promised
and then some

Yes, very much. The 2 tables you have here work togethor to get the "commanded" AFR at WOT. There are many posts on this subject, telling about the formulas and ways to get the comanded AFR. And there is this nice little tool called "AFR Tuner" floating around here, which is most helpfull. (if you can find it). I have spreadsheets setup to calculate the commanded WOT as a function of those 2 tables. It is kind of cool, you can change the tables and see how the AFR changes. Now from what I just read above, need to make "BIG " changes to the AFR. I been making little changes. I now need to go out and make some WOT runs and see what I got. Notice that I say "commanded" AFR.....not what you actually get. Unless you are really good tuner and can get the 2 to be the same. I certainly cannot do that!

Your ride is similar to mine, IROCthe5.7L. I still have stock block, cam and heads. Last time I ran, late august, was consistant in the 14.3s, but had 1 runs in the 14.2s when I brokeout. I know my car has more in it! I am geting good 60' times, in the 1.88 to 1.98 range. I hook good with what I got. See my sig also. I just need a little more top end. I only hit 93+ mph, but it was a very hot day.

You really need to get those O2 mV readings up around 900 at WOT. If you really are that lean above 5000, that could mean trouble. Just dont give up on it.

You guys are awesome! I really appreciate all the input. I kind of gave up on this thing. But I'm going to rip out the laptop and try to get those O2 readings where they should be. I'll keep everyone updated.

There is something that Orr posted that just kicked a few brain cells.

And that thought is: you are likely hitting the upper limit of the MAF. When this occurs no additional fuel is added for the additional airflow. As the MAF can't report the higher airflow.

This is why a lot more fuel needs to be added via the PE AFR table. This table is used to add the additional fuel that the (limited) MAF airflow reading can't.

Also look at the MAF max airflow (vs RPM) table values. Increasing those will help to allow the ECM to use higher MAF airflow readings.

RBob.

I agree. 280xfi cammed 360" motor maxes the MAF by 5000 or so rpm. His setup should also be maxing the MAF out around that point with those higher flowing heads. Cam is not too much different. Right at that point he goes lean, so MAF is probably peaked. Add a bunch of % there and it should start to come around

According to my datalogs, the MAF is maxed out at 254 gm/sec at 4175 RPM's to 6000 rpm.

That is very strange, my readings look almost identical to that, except i havent revved past 6200 yet at least while logging..

My motor runs extremely rich at idle, and super lean everywhere else, before the HSR, it ran PERFECT!

Makes sense, the HSR flows so much at higher rpms it will lean out a TPI type tune.

Interesting, thats pretty early in the rpm range to be maxing the MAF. That setup should run hard when you add the fuel it needs up top

That is the max airflow vs RPM table I referred too. And it has been increased by the screen shot you posted. So good to go there.

Adding fuel via the PE/WOT vs RPM table is what is now required. And yes, it isn't fully correct as it makes up for the lack of MAF airflow report. But, it is correct as it provides the required fuel.

I would add a lot at first to cross over the lean area directly to the rich area. Orr touched on this. The reason is that the engine is going so lean that it can't really get hurt.

If you slowly add fuel the engine can enter the 'burn me' zone regarding AFR. Much better to go way rich then lean from there. And (sorry about this), still put a fuel pressure gauge on there and keep an eye on it.

RBob.

Just for reference, i started with a light modded AUJL bin and PE mode % enrichment vs rpm had changed from stock's 16% added to 40%... First runs the wideband showed around 17 to 1 air fuel on my 383 with MAF maxed in the mid 4000 rpm range. I ended up going to about 75% added to get it near 13.0, and near 88% at peak torque. So you may need to add a bunch at first to get into the rich zone like RBob says. Prevent that detonation/super hot chamber burn zone

Well guys, I added fuel to that table. I got my O2 to read anywhere from 850 to 870 from where it was reading in the 100's before. The car seemed to pull a little better, but nothing crazy. I guess I'll take it to the track one more time. But I doubt I'll gain anymore than 1 mph. This was my first try. I'll do some tweaking to get it closer to 900.

It should pick up. Let us know what it does. richen up the 4400 and above to around 900 mv and it should run hard.

Well here's a before and after. Still some more tweaking to do. But I want to get it to the track before the season ends.

Looks like great progress!!!

I can solve your rich problem down low. You are running 43.5 psi at idle with a 30lb. injector constant, correct?

Ford SVO's are rated at the lb. per hour rating at 39.5 PSI. I would lower your fuel pressure to 39.5 PSI at idle with vac line disconnected, then tweak mid to upper range VE and PE.

Might be worth some ponies and mileage..

Sorry, I should have been more specific. These are the injectors I have: http://fuelinjectorconnection.com/sh...od&productId=5


I have my FP set at 43.5 and the chip is programmed for 32lb injectors.

Any updates on how its running with more fuel?

It feels like it pulls harder. But nothing crazy like I gained 4 mph in the 1/4 mile or something. I will be making another trip to the track before the season ends. If it still runs slow, then I'm getting a dyno tune next spring. Or I'm building a motor for it. If my year goes like I plan, I'm going to build a nasty motor.

good info! Subed to see how it runs!