Looking for some factual knowledge other than opinion or theory. (Long read).
Back story; I have my custom designed TBI system working perfectly except for a bad stumble, when stepping on the...

You may be right in that it was a similar issue.

I stand corrected on this. In subsequent tests it was just as bad (seemed too sensitive to air temperature or something). I thought my first design was bad and tried something different and that was...

In this case, even though the data stream showed all measurable parts working correctly, I had run out of ideas so just started throwing parts at it. Fortunately I had almost everything on hand as...

After replacing everything electronic I still had the same problem. The issue still seemed to be not enough fuel between 1200-1500 rpm but only at manifold vacuum below 10"Hg (65kPa and up). I...

Dave;
I certainly appreciate your efforts but I am at a loss as to where this data is (I only have winALDL and it is finicky as to when it works) and what/where these parameters are to change. Are...

I don't have TunerPro nor any data logs. But here is "the thing"; If I did then which one would be relevent? I've done literally dozens and dozens of files with settings ALL over the spectrum with NO...

>What is the engine combination?<

336 CID (1962 327, 250HP bored .060 over) with stock cam, flat top pistons with an open plenum straight runner manifold. Very smooth stable idle at a stable...

I am stumped by this one. Background; This is a custom made throttle body approximately 30% larger area than a standard two butterfly TBI for a Chevy 350. Everything else is pretty standard; 1227747...

Thank you Thank you Thank you. This is the best, to the point explanation I have ever got.

Hello all. I'm working on the above ECM using TunerCat $42. Can someone explain what the numbers mean in the table 'Accel Enrich TPS Filter Coefficient vs Cool Temp' mean and what changing them does?...

I tried posting this about a week ago but it seems to have disappeared. I have a custom TBI system with a remote IAC feeding the manifold through a rubber hose. Once it goes closed loop the IAC will...

Just to be sure on this table. Does a higher or lower number in the box make it richer? i.e. squirt more fuel. Thanks.

(Open Loop AFR vs MAP table) Are the numbers added to or subtracted from the AFR? Thanks in advance.

FIXED!!!
First off I want to thank all those responders for their ideas which spurred me to more testing. I tried jacking up the BL numbers at high vacuum on fuel table #1 with no results. Set them...

I was about to test this (wasn't able to get out today and it will be tomorrow afternoon at the soonest). If these numbers are what you are using at 0-30 kPa then mine are WAY off. I tripled my...

To answer your question; I tried it both ways and noticed no difference.

You are probably right on the kPa change but as I mentioned earlier I'm having trouble recording on my laptop (hit and miss). DFCO is switched off in the constant table so it should not enter the...

Yes, I agree with you on this 100%. I have increased the (accel enrichment) pulse duration in the 0-20 Kpa range 40% with no effect (thinking of trying 100%). Herein lies the part that puzzles me; At...

Let me explain what I have been doing so far. I’m trying to adjust the program that was meant for a normal dual port GM TBI. The custom throttle body I made up is basically uncharted territory....

IAC seems to be working as it should. Have a few more programs to try.

In my limited understanding DFCO won't function at all without an VSS. In any case I have the DFCO RPM parameters set so it shouldn't come into play. I'll be trying another program tomorrow. Will...

That's easy; Nothing. This system is on an antique Corvette so is very basic. Only sensors are TPS, coolant temp, MAP, RPM.

I have been having trouble recording data on my laptop and seems to be a hit or miss issue. I'm wondering if it would be recorded anyway since the stumble is for half a second or less only during...

I’m looking for help with tuning a custom …747 TBI system. This arrangement runs very nicely except during deceleration when I “blip” the throttle to double clutch downshift it has a “flat spot” and...