$OD Corvair bin file - Got any advise?

[Six_Shooter]

i imagine if they were wired in series, they wouldn't be driven very accurately.

LOL, no, there would be some delay caused by the first coil in the circuit, that and I'm not sure how you would wire them in series, probably by a coil by coil basis?

[tayto]

The Engine specs: 164 ci, 110 HP, stock cam, dual GM TBI-700 throttle bodies. Automatic Trans but cant signal ECM when shifting from drive/park, etc. Used engine with about 100K miles. Heated O2 sensor.

Does your Corvair have a park/neutral safety swtich on the column or floor shifter? You can wire it up to a SPST (4 pin) Bosch relay and send the correct signal to the ECM. I did this on my '64 Chev Impala when I converted it to TBI. Unfortunately I ended up selling the Impala before I could hook up a scanner, but it seemed to work on the little bit of test driving I did.

If you're interested I can post a wiring diagram.

[gkosier]

For the P/N switch, have you looked at the aftermarket one sold by Jegs? I had to weld the trip arm to the shifter lever
and cobble a bracket to get the switch in the right place. Desperate people have desperate ways.

GKosier

[corvairnut]

Yea... Im thinking about the switch which would be better when I shift to drive, but still the more I look at this problem, the more it appears to be a fueling issue. Im really throwing for a life-line here as I have spent at least 50 hours changing every parameter I can find including all the suggested above, and I still have a boucy (porposing) idle. I have a romulator, so most changes have been on the fly, but i'm having no luck. Other than Idle, I am pleased with the run and performance of the engine. The battery voltage issue is where I changed the bin to see desired AFR, but does not seem to interfer with the problem Im having. I have attached a very short log file to show what is happening with the WBO2 also attached. PLEASE look at this log as I have got to be missing something pretty simple...usually the idle is worked out smooth first. It has to be around fueling and the O2 sensor as it runs without bounching when In open loop, but I want it closed to control the "eye burning" richness and make it where I wont have to program each engine that its attached to. Another thing is about the low vacuum... its what they do and run at, so its not a bad engine, just a little worn. The bin is posted above and I made the changes eaglemark suggested, but it never affected the idle...... Ive changed about every setting on this thing....hoping for dumb luck.

SITUATION: The engine idles better wheh I move up the O2 voltages settings (Lean, rich and mean) to about 800-900 range and it brings the AFR to about 13.5-14.0 and runs better (richer), but I know Im just masking the issue. At idle, it levels out and then starts running a little rougher, you see the AFR on the WBO2 move lean and will continue until the AFR is brought back down to approx 14.7 . Its like the engine is not getting enough fuel or getting it late and then back to normal, then right back to lean again.

I would appreciate any help... and I;m buying the next round if we can figure out this one.

Ted

[1project2many]

FWIW it can take a lot of work to make 60's design engines work at stoich. Some just don't. I'll believe you that the engine has low vacuum at idle but why? Is there that much cam overlap? Or exhaust reversion? Either of those conditions will ruin the charge in the chamber and make it hard to get complete combustion. Do you have any intake air heating built in? Many of the early engines with throttle body injection almost required additional heat to burn well. Carbs can do a great job of vaporizing fuel where throttle body isn't always so. The venturi in the carb does a great job of shearing fuel droplets. The only equivalent in TBI is when the throttle is closed enough for fuel to shear as it passes between the throttle plate and body. With low vacuum if the throttle is open to maintain idle this doesn't happen well. It may be a real balance point for you. Can't look at the logs now but maybe when I get home...

[EagleMark]

As you said you've changed about every setting on this thing! Well that's a good time to start with a fresh bin and put your SPECIFIC changes in and try again.

Before you make a lot of changes from there remember this is a wet intake AND low MAP, so as it idles the intake is going to get wet. Make a change and see how it does, watch your BLM INT or WB, rev engine to dry out intake and try again. You may not ever get it dry enough at idle to run CL.

There's so many things changed I can't figure out what/how/why your trying to do?

Open Loop Idle AFR is checked, this changes a lot, read the parameter comments.
Sync MAP sensor reads unchecked?
Sync Fuel at Idle unchecked and supposed to be checked for TBI?
Not sure what bin you started with? Or what bin to start with? Did you start with a V6/V8/TBI bin?

Your fueling at idle is not stable at all, look at highs and lows of Wide Band? But with AE on at idle I'm not sure what to do there? I can't find an $OD setting like MAP to raise this and not sure why it's happening? It may be one of the other things mentioned above? Adding AE fuel at idle with this low vacuum is not helping at all.

Proportional Gains Rich/Lean/Stable/Unstable are all stock to a V8 TBI bin and with that low idle they need to be cut in half at least.

Delta RPM Threshold for Unstable Idle is set to 25 RPM, raise this to 100.

I really think you need to run Open Loop Idle with this low vacuum. The narrow band O2 sensor is lying and messing up your fueling. Just look at log and see where AFR, BLM and INT are stable at start and go downhill from there. This is a wet intake so as time goes by at Idle/low air flow it gets wet and messes up fueling/O2 corrections.

Proportional Flow Gain Factor vs. MAP vs. RPM are high compared to a V8 TBI bin I compared with, there higher at your horrible idle and this does not help.

I see what you did with O2 Rich/Lean/Mean but I don't think that is going to work with Initial O2 value?

Idle MAP is around 50 and you should be able to tune this. But with the low air flow and vacuum it may have to be OL Idle, or at least get this AE at idle fixed, something is wrong and IIRC it was doing that on first log too. Twin TBI has got to shorten up intake tracks which should help but I forget what yours looks like?

Something is wrong? Not sure what because of so many changes? I'd seriously start with a stock bin and make specific changes. I'd really like to know what you started with so I can get a baseline for what you did or what that bin has compared to what I used. Some of the things I mentioned above could be correct for the bin you started with is what I'm getting at and causing my confusion. I'm only used to working with V8 TBI bins in this mask.

[corvairnut]

Your right... Ive changed everything.... somethings got changed back... others didnt. I started with a V8 bin, but its been 3 years and like you said, I made changes and if they made no difference, I may have left it alone. Many setting have been set back to the V8 bin I started with out of frustration.

I will start with a new V6 bin (BJFD) and work out from there. Since I have 2 TBIs, I will half the IAC numbers and about 80% of the V6-4.3 numbers and see what happens. I know I took a "train wreck" and made a "dumpter fire" out of it, but again....nothing seemed to help and most made little changes and from your explaination, it makes since. I should be able to take my VE and spark tables and move them over and should be work and save a lot of time getting started.

Thanks for the explation of the wet manifold and why my changes were not working/working well or only working for awhile.... make sense now. I will get this bin going and post my results.

Thanks

[EagleMark]

I'd also look hard at V6 and V8 bins before I started. With the 1227747 the V6 bins suck, I can make a V8 bin work way better in a six cylinder. haven't done enough weird conversions with 16197427 to see if they had same issues. The big one was V8 bins were Sync fueling and V6 bins were Async. Not sure why or if for some reason it was needed but it does not play well with I6 intakes, they just get soaked.

Now that I mention that I wonder if your dual TBI is firing Sync on wrong sides? Is this possible? Sync = one injector per DRP and Async is both injectors? Your DRP firing is off by what 50 something degrees for DIS... Where's a smart guy when you need one?

[corvairnut]

Using the BJFD (OD mask) showed me right off the bat how they were able to control the idle on that TBI V6. Sync fueling was the key and my little Corvair purrrs like a little kitten at idle.

Having a romulator is a lot easier than buring chips, but it does allow you to make to many changes on the fly and sometimes not letting them play out. (wet manifolds). Your comment about Sync injector firing has got me curious now, so I might have to switch INJ A & B and see what happens....we shall see shortly. I have already set the "DRP to Injection delay" to 60 degrees to account for the DIS. There is a 180 degree offset, but not sure what the purpose was, maybe combine the 2 to get a swap...but sounds unpredictable.

Added: I also had to adjust the min Sync BPW/allowed as I had them at 397 and needed to be a 900 usec to run smooth.

[EagleMark]

I'm really glad it's running better! But your log shows it was running Sync at idle (is it now Async?), but was blipping Async and the AE which is wrong at idle. $0D... in V8 anyway runs Sync but will go Async at WOT/PE for more fuel. My comments about Sync and Async for V8 and V6 were from $42 and all the bins I used for 6 cylinder were Async all the time and ran horrible, I just converted a well known V8 bin to 6 and it ran great.

We have another thread going that has a V6 bin in a factory truck that ran Async and was superceeded to another bin file. I'm awaiting his data to see if the fueling was changed to Sync...

Anyway I'm not sure what happened to you, don't think it was sync, but I'm glad we talked you into a fresh start!

[EagleMark]

I just checked BJFD to your origanal bin posted. Your right and I caught it awhile back, Sync at idle was not checked, MAP Sync at idle not checked, AE limit engine not checked. I still don't know what that origanal bin was but it had several section of code changed that were Item Not Defined! It was not filler space either, it was hex code. SO there was a lot of issues.