Maybe someone can explain the purpose of this table?

I always used AE-TPS and AE-MAP.

Thanks to RBob he brought this to light. For reasons unknown I had this issue with moderately brisk accelleration:

Seems when I accelerate onto Xway from 25 MPH to speed the engine struggles at 2500-2900 rpms. this also was an issue last season as well that I cannot overcome. If i stay out of AE(whats up shows none as CL) then all is well and I can accellerate slowly to 80+. BLM's 126-130 and in line. Or if accellerated fast I move righ past the issue rpms into PE and all is well.

Only area in VE that is ugly is 3000-3200 at 50-70 MAP is pegged at 100. I have been "fudging" my BPC 3 ticks at a time to pull the fuel under 100 there and will check today to see if I accomplished that. But the AE issue is clearly under that as far as RPM's.

i noticed the stock EBL bin for 8746 has very low % values 400-1200 RPMs and all zeros above 1200. so I added values in RPM multiplier at 2200-3000 RPMs and it seemed to help but little. So I am continuing to add in that area and last increase shows I am at the following:

RPM
400 22%
600 36
800 52
1000 50
1200 48
1600 25
1800 22
2000 21
2200 18
2400 14
2800 12.5
3200 7
3600 4

I have addded to the entire table by a percentage at a crack three times now and added a bit 3200-3600 to taper off. Issue still exists and is worse on a hot intake manifold.

Should I add more yet to 2400-2800 and forget the surrounding %? Does this seem correct?

The purpose of the AE RPM Multplier % table is to tune AE according to RPM. For no change to AE vs RPM make all entries 0%. Can make the entries minus (to subtract AE), or plus (to add AE).

RBob.

I have been fighting an AE problem for a while. Actually gave up for a week or so, to catch a break.

Did not realize that you could use negative numbers in that table.

Thanks!!!!!!!

it appears my issue is rpm related. it is like the gas is shut off at 2400 when onset of AE is 2400. any other start of AE at other RPM seems much better. wierd to say the least. I just added another 10% at 2400-2800 so will see the result this evening.

Is a wideband quick enough to pick up on AE? I was thinking about getting one because after a while it all seems the same to me, lol.

What AFR's should one look for under AE typically?

browse Innovate website. oh yes it is very fast. not sure if there is a perfect A/F to shoot for. i would say lean it out till you get the lean pop and then enrichen so it does not occur and not so rich it "gurgles".. my WB sensor is broken today. a lot is just what feels good on acceleration. PE -WOT is a different matter.

Thanks Ronny. Are there are good guidelines to go for?

This is what I'm running now for AE on a 350, full exhaust w/ headers and a 206/212 cam. It's basically double what stock is, and it feels good but not quite what I think it should be. What do you think?

AE vs Diff TPS % Table

50.0 8239.75
46.9 7751.46
43.8 7324.22
40.6 6774.90
37.5 6286.62
34.4 5859.37
31.3 5493.16
28.1 5187.99
25.0 4882.81
21.9 4516.60
18.8 4150.39
15.6 3601.07
12.5 3234.86
9.4 2624.51
6.3 1892.09
3.1 976.56
0.0 61.04

Thanks,

John

PS Sorry to hijack the thread lol.

each set up is different. cant compare. i have 22.5 lbs FP, 80 lbs injs and 350 CID. I bet the sq inch of the intake manifold(wetting) factors also. same on size of TB's and size of head intake runner(170cc). I think my AETPS starts at 122 Usec and ramps up to 1100. for kicks i put minimum in AE MAP of 61 Usec accross the board. now I just worry about TPSAE. maybe that was not smart. AE-TBI is a pain in the ***.

You're running 22lbs of pressure on 80lb injectors? Holy crap what kind of an engine are you running?

previous crossfire vette. 350 cid, xram, 2.0 TB's, 454 injectors, edel rpm aluminum 64 cc heads, crame 2040 cam 210/216 @.05, crane roller rockers, ceramic hedman 1 5/8 headers, dual exhaust/crossover, hooker aero chambers, 7747. Innovative WB.
CHANGES COMPLETED 10/13/2004:
7.4L TB on Holley TBI manifold(Projection), Summit AC with K & N, Aeromotive FP reg, Comp Cams 224/230 @.05 114 LSA, Innovative input of tps/rpm/map data.
09/2005 fresh paint(red of course)
08/16/2006 added Prominator- 8746 ECU with EBL, IAT sensor being added following week.

It is the cam i think...

Yeah, AE is a bastard to tune. I would like to get back into it. I have the GMPP tbi vortec manifold, and it's heated and doesn't require a lot of AE. found that one out the hard way-
Anyway, I went back to almost stock EBL AE settings, taking a little out of the lower Rpm multiplier 600-1000 rpm area to get rid of a little hesitation. Hey ronny- how much MAP AE are you running compared to stock EBL? Do you run an open loop idle?

Mike

i pulled it all out cept minimum 61usec as an experiment this last tune. seems i dont need map AE? I am probably wrong.

also early this spring i tried equal amounts of TPS and MAP and that did not work well for me. My dead spot 2400-2800 may be something other than AE. i am assuming today it is AE.

Since I can't seem to crack the code on this, I think I'm going to add some MAP AE PW in the 22-2800 rpm area. TPS AE seems ok. I hit the gas in that range, and i see the INT dip a tad, then it goes lean =140 INT. The truck goes forward, but it seems like it could use more. I'm thinking more MAP AE in the 50-70 kpa area. The MAP AE pw table refers to change in MAP or just actual MAP kpa when AE kicks in? not sure on that

Mike

Ronny,

That car sounds like a weapon lol. What do you mean by 2.0 TBI?

Hey Mike, what are you running for an engine?

I guess I'll just have to keep playing around with AE. I've taken a break from it until I can get my upper RPM fuel issue taken care of as I've been told different injectors or pressure will mess with my AE.

Catch ya later,

John

2.0" TB bores. Stock big block bore.

27 psi on same injectors here. Little larger engine though.

Only 2 injectors.

I am fighting too much AE. Enough to drop AFR to below 10:1 at WOT. Hard for me to figure out how much of the problem is MAP and how much is TPS. Started reducing the TPS 10% at a time and will see how that works.

Tried reducing them both by 30%, but then part throttle AE was way lean. Reminds me of the problem that started this thread. It seemed to have a dead spot right off of cruise, 2800-3300 rpms. WB showed not enough AE.

Also, the multiplier serves to linearize the AE with RPM if its pulsewidth based. As the RPMs increase, the ammount of AE delivered does as well as there more injector firings during sync AE. GM has this in their later cals., and the table is some combination of linearizing the AE as well as tweaking the volume delivered with RPMs when sync AE is in use.

FWIW, performance manifolds with lots of wall area need LOTS of AE and DE. And, the AE needed varies with the conditions. The AE is what drove my injector and fuel pressure selection. 65s running at 30 PSI. The engine only uses around 60% of the total fuel capacity, but the AE uses 100%+ of the capacity due to how much fuel is needed in some situations. It seems like more is needed down low with the AE volume being fairly flat from 1200 RPM on up.

Thats actually not that much pulsewidth. Between my sync AE %DC table and manifold temp and RPM multiplier tables Im running around 50-75% DC during most large transitions, and the resulting pulsewidth is more like 7,500 to 10,000 usecs at lower RPMs. It could be possible that 1100 usecs is just a drop in the bucket. Also, the MAP is what seems to drive the AE requirements. It may be easier to use the MAP AE tables and transfer all temp based multipliers and filter coefficients to the MAP AE routines. While everyones setup is unique, for me, the MAP seems to provide the most accurate representation for how much AE is needed.

I'm running the GMPP 350HO with a small block tbi bored to 50mm with 90/lb inj's at 14 psi. It's ok but I know there's more in there somewhere, and I think the AE is where it will be found. I think my TPS AE is ok, but I believe the MAP AE is suspect. About 2300 rpm on a decent accel, MAP AE should last longer and provide a more sustained boost, and that's what I''m lacking. That might be flawed hopefully dimented will say something...
I think I'm going to give those rpm's more multiplier % in the table. who knows.

Mike
----------
I boosted the hell out of my lower rpm AE in the mulitplier table, and when the engine was cold it was way too much AE, like driving into a wall. Once the engine warmed up, there was hesitation and lag then vrrooomm. So, I pulled the values in the lower RPM areas and ended up decreasing them to less than stock EBL settings and it runs good in those areas. I also have a kind of dead spot in the 2k areas, so I'll just add a little % and give it a shot.

Mike

I'm at 35 psi on 90 lb/hrs and looking for more

I've been watching some AE tuning threads and it has me looking at my calibration. The blower causes the need for AE to be delivered over a longer period of time. On the EBL when you lower the AE filters to accomplish this it also increases the amount of AE fuel delivered (Rbob). My delta TPS and MAP are only 75% of the stock EBL.bin. The coolant comp AE table is about 20% of stock. The blower makes for a nice "fuel blender" at during cold temps so not as much AE is needed then.

Running this combo it's easy to stall the engine with too much AE. I've done it before. The WB dropped below 10:1 and the engine stalled. That's ALOT of fuel...

I've been tuning to best "feel". If the engine dips into the 12's and 13's AFR on AE and it "feels" good, then I'll shoot for that.

Getting the AE right everywhere is a real nightmare. You auto guys are lucky. With a stick, you need AE every time you shift gears. I remember that with my standard vortec manifold, the AE was always a moving target with the stock AE routines. After the manifold heat soaked, the car would totally puke as soon as I hit the gas and blow smoke. About two minutes later it would be ok, and then after the manifold was cooled down by the gasoline vaporizing in it, the car would have a vicious lean hesitation along with backfiring out the TBI. It did this every stinking time I hit the gas or had to shift and get back into the throttle. Made the car a total drag to drive. Ultimatly I went with an airgap manifold and custom programmed my own AE routines as well as referenced all temp based MAP AE corrections on the manifold temp alone. Fixed all the problems but after all that effort, MPFI didnt look like such a bad option. With vortecs, my only other real option wouldve been to use the GMPP vortec TBI manifold, but that wouldve probably cut into the top end performance.

The transient operation with a wetflow system sucks...

The lean popping has me curious- maybe I have too much AE in. It has never popped- ever. even when I first drove it with the bin AFU.
I'll try leaning the AE out and see what happens. I hear ya on the wetflow setup- definitely a beotch. Many variables to deal with. I think it might be a good idea for me to lean it out a bit and see what happens- the TBI vortec manifold gets hot in literally three or four minutes. With the hotter manifold, the fuel vaporizes faster and therefore less AE is needed, yes?
I might switch to a port fuel setup once I get hog refined.

Mike

Yeah, the hotter the manifold, the less AE needed. Cold you need lots of it because teh fuel settles out easily with changes in MAP. Hot, you need very little. Mainly just general enrichment for acceleration. Cold, it seems like teh AE required increases by about a factor of 8-10x. With the proper algos, the AE is fully tunable, but it seems like it requires a good deal of compensation for all the various effects to get it to work well year round. Either that or run a fully heated manifold with heated air, but that really seemed to hurt the performance. I noticed that my 0-60 time dropped from 6 to around 5 seconds by switching to cold air intake and an unheated manifold.

Your probably already aware of this, but to really see whats happening, you WILL need a wideband to see whether its going lean or rich.

This is one of the main reasons why I stuck with the stock intake. I have to daily drive the truck and it sees -40 degree starts in the winter all the time. Downside is I'm not making much power, lol.

Dimented, you mention that you would have considered doing MPFI. In your opinion what would theoretically be the best option to convert from TBI to Multiport?

John

last season when my wideband was functional and I had similar #s in AE TPS and larger numbers in AE MAP I was seeing 10.1/1 on WB for the brisk acceleration. too fat. and 12.0/1 when the PE came in. again too fat. this season and end of last i pulled a lot of AE out to start lean and work to rich. that is when that nasty bog developed at 2400 rpms. granted I have little AE in car now and that was my plan to sneak up on correct levels. 1000 rpms to 2200 rpms seems fine, that is if you drive with little pedal action. as is 3000-4000 the AE is OK. also I moved my PE threshold from 40% to 50% this season and now that may have a A/F spike lean right at that AE-PE transition so that may contribute to issue as well. having PE at 40% showed an overlap of AE and PE in my WB logs. Now i can see AE decay and then PE come in with a lean gap but that is SOP as the WB sensor is dead again a week ago? maybe the RPM multiplier will prove to be invaluable. I added more fuel at 2400 last night but did not test drive. I will most likely add more AE MAP and leave values in AE-TPS as is 122-1100 in even increments of 61 up table.

Sierra,

I dont think I wouldve switched on this car due to all the agrivation, but the thought has crossed my mind that MPFI might be easier to deal with on my next setup. I couldnt be happier with the results, but it does take a good deal of effort to tune some things, depending on the setup.

With some changes to how the fueling is handled, Ive managed to get most things to be easy to tune. The main fueling only takes about a half hour to tune as its just calibrating the MAF. The SA takes a couple of runs over a few days to find out what timing the engine likes, and some tweaks as the weather changes. The AE takes a full six months to tune as the weather goes from cold to hot. As long as I dont change the intake around, my tuning is pretty much done, but if I change the intake tract around, it starts all over again...

I can say that you definatly need that heated manifold in your location. With a CAI and non-heated one, I get into fuel distribution issues at low speeds when its colder then about 15 deg F. out. The engine wants to stall when the MAP comes up and the RPMs drop below 1k. Starts and runs fine, but the stall saver catches the motor every time it idles down for the first few minutes of operation. This, and it needs TONS of AE to avoid tip-in leanout when its real cold.

As for the MPFI, an aftermarket MPFI intake may be easiest. Youd then just need a new fuel pump and other items. The TBI could be stripped of its pod and used as a TB instead.

Thanks for the info dimented. When you are talking about converting to a MPFI intake, is that the edelbrock setup?

Id avoid the edelbrock setup like teh plauge... People have reported bad results. Id use a carb type manifold set up to accept injectors, or TPI if you plan to keep the motor near stock.

Your PCM can also support MPFI/TPI, if you choose to go that route. It can fire saturated injectors in teh same manner that the TPI ECMs can with some minor changes to the wiring and memcal to select the correct firing stratagy.