Turbo 2.8 tuning with logs and tune(need help with tuning)

[WillExoIX]

Its an AEM Uego wideband and I always wait until its warmed up before I start so it should be accurate.

You can still have false readings, in a situation where a misfire dumps unburned air/fuel into the exhaust and is read as lean.

Have you tried a lower cranking pulsewidth? My understanding in that MS1 will do 3 squirts per revolution during cranking on a 6 cylinder. So when you compare the cranking PW to the PW while running, you have to keep in mind that the number of squirts could be different! If you are running only 1 squirt or 2-alternating then I would definitely try a lower PW for cranking.

That 0.9 degrees of cranking advance sounds less than ideal. I'm not sure what your ignition setup is, but I would say double check your settings and maybe verify the spark with a timing light.

Tuning cold starts can be tricky. When the engine first fires, the revs jump up, MAP goes down, fuel in the intake evaporates. Then the opposite happens. Revs start to drop which causes MAP to rise and fuel in the intake to condense. This is when the engine will die if warmup/ASE aren't enough.

I had wondered about the cranking advance, but the base timing is set right around 0. Then its compensated for in the MS to set base at 10 once the 5v is supplied on the timing wire. Stock base timing is 10, but mine is set to 0 because at 10 the rotor strap doesn't line up with the posts on the cap and causes a mean misfire. Its a brand new dizzy too go figure. Also, even with the cranking advance where it is it catches as soon as I turn the key and fires up, it just stalls shortly thereafter.

2 squirts alternating is how it is setup right now. GM HEI 7/8pin ignition, Hmm, cranking is set to Time based and a 10 degree Cranking Advance Angle. But if it were trigger return I would have to square away that rotor phasing issue cause trigger angle has to match cranking advance.

But with those settings it runs like stock and is as smooth as it was before, so the base timing and the offset (?) cancel eachother out, replicating the stock timing flawlessly. Its an electronic advance as well so no points or vacuum advance.

I have been playing with the ASE, because that is activated right after the car comes out of cranking mode, and ASE is a filter for the WUE analyzer. So I have been trying to get it to stay running after cranking, cause if I don't bring it to around 1500+ rpms it will stall, plus it runs lean for those first 15-20 seconds. So I know I will probably have to add some WUE, then add a little more ASE to see if it will catch itself.

Worth noting again I have no working IAC, and after getting compression back on 6, the idle was dropped from 11-1200 in park to closer to 850-900 in park. So I may need to open the throttle screw a little more cause the rpms will run a little low and I think that also has something to do with it wanting to stall not running an IAC.

[WillExoIX]

It needed more afterstart enrichment. Also added another 1ms to the priming PW to get that initial drop in the AFR and it should start pretty quick from here on out. Only need to be a hair on the pedal, like 3-4% on the TPS then it catches and I can let off it and it will idle without stalling.

Now to put the muffler back on, lol.

[WillExoIX]

So 2 days ago, I had this guy in front of me doing like 20 under the speed limit, so I passed him and felt the car shudder.

Crap, I forgot to unlock the torque converter! Took that out and the 3-4 clutch pack. Still have 1st and 2nd though. I have an invoice coming tonight on parts to fix it, then I will be pulling the trans and breaking it down.

Expect updates in somewhere around a month, lol.

[WillExoIX]

So I have decided to do away with ASE, and just try to get it to start reliably with only the cranking PW table, and the WUE curve. I am also starting to use FSE, so we will see how that goes.

I am about to go out and get a log for another issue in another thread, But I will post the log here as well for any tips on whats happening with startup.

Right now primarily I would like to get the startup a little better. I will crank it without using the pedal to show what it does with no throttle input(no IAC valve). Then I will do what I normally do to get it to start and hopefully something in the log will stick out to someone who can point me in the right direction.

[WillExoIX]

Here is my tune and a log. Really for starting you only need to look in the beginning. The 3 pumps is to activate FSE, after that I just bumped the WUE up in the current temp cell.

Any clue what the rich/lean swings are caused by?

[WillExoIX]

Looking in the log, I see the spikes in rpm and afr correlate with going in and out of cranking. Does that mean I should raise or lower the cranking RPM? Its at 400rpms currently, but it looks like my car cranks at a much higher RPM.

Another curious thing I see is the cranking timing down at .9*. Cranking advance is set at 10*. Could that have anything to do with the fact that the car is set at 0* base timing? The trigger offset (I think?) is also at 0* to match.

[Matt Cramer]

Yes, raise the cranking RPM - you want it entirely in the cranking range while cranking.

HEIs have the bypass off while cranking and spark at whatever timing the distributor is timed to.

[WillExoIX]

Yes, raise the cranking RPM - you want it entirely in the cranking range while cranking.

HEIs have the bypass off while cranking and spark at whatever timing the distributor is timed to.

Would this cause a problem if I am pulling the 5vref for the bypass from the TPS?

EDIT-So should I bring the cranking rpm up to 500 or 600? Or 50-100 rpms below the lowest rpm in gear?

[WillExoIX]

So I am amazed that nobody picked up on the fact that having 0* base timing was causing the hard start.

I reset the base timing to 10*, turned the car off, plugged the bypass back in, changed the trigger angle from 0* to 10*, started the car and no more hard starts. Won't know for sure until I get a true cold start, but put it this way; The car started and ran before I finished turning the key....

How did nobody see that? With the bypass being blocked in the ICM for cranking, and the ICM using base timing for cranking, and mine being set at 0*(technically .9*), it should have been painfully obvious. The only reason I didn't see it till now is because nobody could even point me in the right direction.