Tuning my 347 with rear mount turbo

[2000StreetRod]

Altering Open Loop Delay Blending Ramp solved my problem: tip-in blend

 

[Dono]

Thanks for the info.
Unfortunately my strategy doesn't seem to have this variable.
Tim's might though. I'll make a point of looking for it.

 

[Dono]

To set up the Failed maf transfer function, It appears it can be built based upon:
RPM
TP absolute
load

It's probably a good idea to do this anyway, just in case the maf does fail at some point. I think I can start this with some existing logs.

 

[vroomzoomboom]

soon !!

 

[4pointslow]

Calibrator status

Thanks for the info.
Unfortunately my strategy doesn't seem to have this variable.
Tim's might though. I'll make a point of looking for it.

You may have to have what's called Calibrator status to access stuff in your tune that may seem missing. Some things are blocked from you like VCT tuning and drive by wire if the vehicle had them. Your vehicle doesn't have them. Those two I just use for reference because you could ruin your engine or have the vehicle take off by itself if you screw them up, that's why they are blocked.
To get calibrator status you are supposed to buy Greg Banish's CD or go to a 1500.00 class. I bought the CD.

 

[4pointslow]

Maf

To set up the Failed maf transfer function, It appears it can be built based upon:
RPM
TP absolute
load

It's probably a good idea to do this anyway, just in case the maf does fail at some point. I think I can start this with some existing logs.

You have to dial in MAF first(because load is calculated from the MAF). Try not to do things out of order.

 

[Dono]

My maf is close, so I started with the data I have. I know it will take a re-adjust. Its obviously a million miles closer than it was now.
I spent some time with Vroomzoomboom on some remote tuning last night. I doubt he will get out for a drive tonight. The snow's flyin around.

 

[Dono]

Quick question:
When working on the load with failed maf table, should I be using TP absolute, or TP relative pid? I was thinking about this and shouldn't I be using tp relative?

I'm pretty much dialed in on the low load area's, and its raining. I thought I'd focus my attention on failed maf a bit.

I am still struggling with warm starts. I first added crank air, and hear the motor spin faster, but not start. Now I'm adding crank fuel in 10% increments. It's slow going as testing takes time (motor must be warmish, and have sat for a while).

 

[4pointslow]

Tp

I believe it is TP relative for that table, my reasoning is because it has 0 at the bottom and Real TP voltage never hits 0 volts/counts unless there is a problem.

 

[Dono]

I moved my wiring over to my iat sensor in my lower intake manifold tonight.

Strange thing is, it reads 100 degree's F with the motor cold. That's not right. It's 70 degree's in the garage, and the motor feels cool. Umm......

I measured the sensor in my Maf, 28.76k cold. No ambient heating from the motor for sure. Looking at previous data logs, I can see the sensor is reading correctly in livelink.
I measured the resistance of the sensor in the lower intake, and its just over 5k and reading 144 degree's F with livelink.
Tomorrow morning, before I leave for work, Ill measure the resistance of the manifold iat sensor.
Here's a chart that shows what temp to expect the pcm to read at different resistances.
http://www.aa1car.com/library/air_temp_sensors.htm
The curve isn't exactly linear, but adding a resistor might make the slight difference where required.

I'd ignore the manifold sensor and just go with the maf sensor, except I want to spray w/m and I keep reading that this is very bad for your maf, but at the same time I want the sensor to read the cooler temps when spraying. Problem currently is that the manifold iat sensor will cause the pcm to pull timing almost all the time. This just won't do.

Maybe there's a reason why the iat sensor is no longer installed in a lower intake? I'll log while driving and compare 2 logs, one being with the iat sensor in the maf.

 

[Dono]

There seems to be about 10k ohms difference between the two sensors when cold. The manifold iat sensor reads higher when cold.
I don't think this is a problem though. At the temperatures that count, it seems to be accurate.

I completed a 12psi pass on the highway today. I was logging, so I was looking for an opportunity to do this. iat hit 158 degree's. Not horrible, but they will still climb higher over a full wot pull.

I'll be able to look at what temp the pcu pulls timing and how much. Maybe some light tweaking there will be a good thing as I think at 158 I have already retarded timing 3 degrees. I could probably move that number up and adjust my borderline knock accordingly.

There was no detonation heard. Pulled nice and hard. I don't have much timing up top right now. I think I'm at about 19 total, and if the pcu pulls 3 degrees due to temps I'm at 16 total. I'd rather be conservative till my combo if set up perfectly and then inch the timing up.

I'll be interested what happens with the new faster spooling turbo as far as load at lower rpm goes. I may need to pull more timing in the upper mid load areas.

 

[Dono]

Not to beat this iat sensor topic to death, but I'm going to beat this to death. Looking at the wot log, as I ran in to boost for the pass, my iat's kept dropping. They wen't from 126 degree's to 112 in boost. I'm not sure why. I know its colder out, but I am surprised. At 12lbs boost, I expected temps to be going up.

Oh, and I might very well be re-normalizing my tables. In the tables, max load 1.2 I hit a load of 1.17 during my 5 second pass.

I don't think it would be wise for me to go much past 12lbs boost. I think this is well past the safe zone of a stock block. If the new turbo can have the boost come on much earlier, and hold 12lbs to red line I'll have a monster on my hands.

 

[Dono]

I have another odd issue.
My stft's quit updating at idle, and my wideband reads about 11.
The smell also tells me Im way rich.

My initial thought was that since I was tuning via stft, the last time they report is almost 1, then the afr's do so rich that the narrow bands are out of range.

So, I started tuning idle via wideband, targeting 14.4
Now, the last time my stft's report thay are at .89 trying to richen up the mixture even though Im running just over 14 afr on my wideband.

These logs are taken immediately after going for at least a 10 minute drive, and my temperature reads fully warmed up. I was hoping to find some crazy setting like 'idle fuel inrichment', but havn't.

Anyone have any thoughts on this?

 

[4pointslow]

I am not getting emails when new postings are happening sometimes. Just saw this.
Can you send me the datalog?
If STFT stops adjusting it went into open loop, maybe due to a fault or false temperature readings.
What were you adjusting in the tune right before this started happening?

 

[Dono]

I'm not even sure when it started. my open loop lag is still zero when this occurs. It might have something to do with the oat sensor in the lower intake. the fact that iat's are so much higher, and fall under wot/boosted conditions makes me really question its accuracy in that location.

I'll send you a log.

 

[Dono]

Not much new, I had my air conditioning recharged as the motor is holding up.

I gave up on the iat senor in the lower intake. bad idea. too muck tuning t try to get around the issues, and still get marginal results.
I have a new turbo waiting to go in, but I'm still questioning the t3 hot side. boost might come on way to fast and also cause too much exhaust back pressure.

I had a header gasket blow (drivers side, thankfully), and that's it for mechanical issues.

I have been leaning out the a/f ratio and pulling timing. I'm at 17total and 9 lbs boost now. today at about 40mph I hit the gas and the rear end laid rubber on a road with good traction. I'm going to say that the rear mount turbo seems to like less timing and leaner a/f ratio's. tuning seems to be everything with a turbo and its ability to spool. a lot of trial and error. once I have the turbo spooled, part throttle keeps it at 4-5 lbs boost.

I'm finally starting to enjoy the benefits of all this learning.

 

[vroomzoomboom]

sweet! now let see if you can make Dauphin in 2 hours

 

[4pointslow]

Tim, What's Dauphin?

Dono,
When you say 17 total do you mean 7 degrees advance in the tune and the 10 base timing advance?
Laying rubber at 40 mph is awesome! must be getting fun to drive!

 

[vroomzoomboom]

Tim, What's Dauphin?

dauphin is around 4 hours from don. it is also the place he is TOTALLY looking forward to being this weekend!

 

[Dono]

Yes, 7 advance in the tune at any load over .8
I also think I had too much timing in around the .5 load area.

Interesting note on gas mileage.
At low load (idle/highway cruise) I leaned the a/f ratio to about 14.9. mileage went up quite a bit. I think I'm seeing the same gas mileage that's the same as when I bought the truck. It might even be a hair better. I don't want to go any leaner for many reasons... narrow band o2's loose accuracy the further out of range you go, chemically bad exhaust rises due to the extra air in the combustion chamber, and exhaust temps rise. I'm learning, so hopefully applying this to Tim's tune will give the same or better results.

4pointslow, Dauphin Manitoba hosts a annual countryfest. its huge for their local economy. http://countryfest.ca/. We will be camping (if you can call it that, drop the back seats, blow an air mattress up in the back, screen over a window). Food and beverage is there, and reasonably priced. A good time is had by all. problem is, I am not a real country music guy and don't sleep well at this type of thing. Should be sunny and warm out though, and the sights will be good, lol.
Its about a 4 hr drive going the speed limit. should be a good mileage and reliability test.