Ronny

logging with my Innovative WB. finding a significant delay from the onset of TPS(log of sensor data) throttle movement to the onset of AE(log of actual enrichment event). this is a fully heat soaked manifold at 70 deg ambient air temp. i actually see two AE "blips" of equal quantity and equal duration. it would appear thevalues in tps/ae and map/ae net same result. issue is the dreaded bog follwed by the onset of AE and resulting kick as car recovers from bog. mostly at engage of clutch from stop and 1st to 2nd geear shift at normal city speed. now the delay from onset of tps to AE is anywhere fron .25 to .60 seconds per WB log! why the delay? which sensor reacts faster? TPS or MAP? i recently removed considerable value from AE/MAP at 0/20/40/60 and added to TPS 0/3/6/9/12/15% assuming the TPS reacts instantly and MAP needs to see drop in vac. so first AE blip in log is TPS and second is MAP.i my AE/TPS is currently 0 122 3 183 6 244 9 366 12 427 16 610 19 732 22 977 25 1099 my AE/MAP is 0 61 20 61 40 61 60 122 80 244 the above nets a 11/1 A/F consistently at all levels of TPS. comments and help please.

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JPrevost

If that AE is in usec and it's a 7747 ecm with any size injectors at stock fuel pressure than I'd say you're using too much AE in your VE tables and not enough in the AE tables. That MAP AE is rather low. I'd double everything in the 40-80 cells and put the 20 in the 100 range. Decrease the low RPM MAP cells that aren't around your idle (off idle to 100kpa) and see where that leaves you.
I see a previous and completed in your sig but still no fuel pressure or injector size. Since the 7747 is time based AE it will change with your flow rate... which is annoying to say the least.

dimented24x7

There are also filter coef. for both. You can change how fast teh AE decays out with that.

Ronny

injectors are 80 lbs and FP is 13.5....

please explain the comment: I'd say you're using too much AE in your VE tables ??

how is the VE in anyway related to the AE?. I thought VE was for setting the basis for fueling in CL. maybe that comment is too simplistic? AE is OL or independent of the VE? Or so I thought.

Quote: Decrease the low RPM MAP cells that aren't around your idle (off idle to 100kpa) and see where that leaves you.

Again i am assuming you are refering to the VE tables. so if i understand correctly i currently idle at 800 rpms/30 map. i therefore reduce VE tables in all of the 400 /800/1200 rpm cells except those cells that i idle in and those directly around 800/30(ie. 400/30;800/20; 800/40; 1200/30). those are the bordering cells to my idle cell.
Q is if i do so what will prevent the BLM's from attemping the fuel correction again.? IOW if i decrease the VE wont the BLMS add fuel. i just reconfiquerred my VE tables due to new cam.

Ronny

Hello dim. i have that feature in TC but my issue is that the AE is clearly coming into play too slow. late in arriving. the duration i am OK with. i think. my logs from yesterday number about 12 and each one i can see the A/F spike super lean like 40/1 or off chart then .25/.50 secs later here comes AE and pulls it down to 11/1. at that point car responds nicely. also on steady cruise i am fine with toggle around 14.7/1 BUT deacceleration enleanment puts me way lean at like 30/1. maybe that is as expected. i may be drying out the manifold plenum and intake runners in head completely when that happens. maybe that contributes to the bog???

Ronny

is it possible it takes .25 to .50 secs for my Innovative to read the A/F down at collector as a change. meaning the A/F change is occurring sooner than the log shows?

Dominic Sorresso

Ron,

Are you sure that 13.5psi is enough FP for your WOT requirements? Just an FYI, but with similar setups and injectors,'
I'm now using 20psi for FP.

Ronny

Hi Dom.
i am aware it may be too low. i have only been running this cam for 3 weeks last fall and 3 weeks this spring weather permitting. i have been easy on the throttle in that time. i am reworking VE tables and only once this spring did i keep in PE for any lenght of time. with AE timed out and PE involked i saw 13.5/1on WB commanded to 12.5/1. i will pump it up for sure but want to run the least FP that will allow me to see 12.5/1 on WB and then again on dyno. i may end up 20 lbs as you state. working bottom to top as they say. SOP showed same TQ on bottom end. seems the holleymanifold helped with that(longer runners/high rise dual plane). comes on cam about 3500 rpms. only had once at 5000 rpms as stated above. felt like it needed more gas for sure. kinda nosed over at 5000 rpms.

JPrevost

If you can get your BLMs to change in the 400-800 and even low 1000 rpm and 80-100kpa cells than I'm impressed. That's what I mean by having AE in the VE table. You go through those cells so fast there isn't any learning unless you're so lean that it keeps backfiring through the intake, which in that case it still isn't doing any "good" learning.
I've seen countless calibrations that use almost no AE in the normal AE tables and all in the VE tables. Think of it this way, the learning of the BLM takes about 2 seconds, when you open the throttle does your engine ever stay in the low RPM high MAP area's for 2 seconds? I hope not else you need to get a new transmission that kicks down.
There are lots of ways to tune and tuning AE with the VE table can be necessary with the 7747/8746. More so the 8746 because of it's rather weak TPS AE routine.
Does that make any sence? It's the same with SA, some people don't reliaze that in those quick opening throttle your MAP shoots up and the timing in the low RPM high load is very critical to how an engine responds. The scan tools are too slow to show it but it doesn't mean the ecm isn't in those cells!
Knowing your tables now and the pro-jection manifold those values don't seem to far fetched although I still think the MAP AE could use a bit more and this is where you'd want to remove the fuel in the VE cells.
Think of AE this way, it's added fuel so the VE is there PLUS the AE fuel (unless they overlap pulses and the async gets dropped but we won't go there).

wade84

I am having similar problem, can not get the AE/VE combo at low rpm/high map right. too lean or too rich. Are you saying more timing might help burn that extra gas. It is only a two second blip but that is 60'.

Dominic Sorresso

The objective is to be at the desired AFR with enough headroom in the Injector Duty Cycle. You want to add that to your parameters for arriving at the necessary FP to achieve required AFR. So my 20psi gets me 12.4:1 while at a DC% of 85.
Also, the FP should be at a point where your commanded AFR ends up being the observed AFR. Doing this first minimizes the number of times you'll need to re-map the VE table.

Ronny

thanks JP. that does make sense. i already added fuel in AE/MAP before i read your response. i will burn a second chip pulling fuel out of that VE area and try that.