Old fart, First tune https://forum.hptuners.com/images/icons/icon7.png

[Homeless]

As an "old school" engine builder in my earlier years, I am entering into the tuning world with the help of my son...who lives 100 miles from me. Because of the distance between us, it makes it very hard to take it to him for any tuning adjustments.

I bought the HP tuner software and MVPI2+ so I could grab logs and e mail them to my son and then upload changes he sends back to me. I dont have enough knowledge to make any changes myself so I just upload what he sends to me.

Before I dive into my request for help, I thought I would give you the engine details.

I have a 2007 Suburban LTZ with a "Y" aluminum block 6.0. The engine dropped a valve seat which required a rebuild. It had 234K on it at the time.

I had it bored .30 over with flat top pistons.
Removed all the DOD garbage and installed the following from Comp Cams

54-456-11
CAMSHAFT, LS1 269Lr HR-112, Double Springs and lifters for this cam

5560-KIT
DOD DELETE COMPLETE KIT FOR
GEN IV 6.0L LS ENGINE

3172KT
TIMING SET, LS2 3 BOLT CAM/4 S
ENSOR HUB

Cats have been removed and it has a 3 inch MBRP exhaust. I just bought an AEM 30-0300 X-Series Wideband UEGO AFR Sensor Controller Gauge but I dont have it installed yet. I will install it using the serial option as opposed to the Pro version which I did not purchase from HP Tuners.

The suburban will pass anything except a gas station and pulls strong and hard from about 4 grand to 6500 .

My current struggle is cold start issues, once I get going, all is fine. I did try to research this on my own but it is over my head at this early stage of trying to learn. I am hoping someone can tell me in layman's terms what is going on with the tune. Once i understand what the problem(s) are, then I can learn what it takes to correct them.....I hope

Soooo my question is... would someone take a look at my log from a cold start earlier today and take a look at the current tune. I just dont understand why it will start fine and after I let it idle for about 10-15 seconds, it will die as soon as I put it in reverse. It will restart fine and idle fine but if I don't let it idle for about 30-45 seconds, it will die again. once I let it idle long enough, it does not die and I can get going.

The log file is a trip around the block with a quick hard acceleration near the end. The tune file is what was uploaded last weekend when the cats were removed

Thanks in advance for any assistance or comments

[kevin87turbot]

There are a few things that need to be addressed in the tune. The VVE tables need to be properly calibrated.
The timing tables are unusually low, but aren't affecting the idle.
The PE delay is still set at 3 seconds. That's why it's a slug until it hits higher rpm and the PE mode is activated.
The min airflow table will likely need to be increased a bit more as well.

Load this one and see if it helps.

Burban cat del kw mod.hpt

[JustinRaney]

may i ask how did the engine drop a valve seat and what were the symptoms?

[Homeless]

may i ask how did the engine drop a valve seat and what were the symptoms?

Actually it was weird. I had been pulling a trailer from a short trip and was putting it away. I backed it in and unhooked it. When I started the Suburban to pull forward, it made an awful noise and locked up. I have dropped valves before but this is the first time I have dropped a seat

I will post pics if I still have them

[Homeless]

Found The Pics

9856ba80-9c10-4b1b-bd7a-cc5a1e641fca.jpg

245203af-e6d6-4b4c-a058-c23923a222db.jpg

[Homeless]

There are a few things that need to be addressed in the tune. The VVE tables need to be properly calibrated.
The timing tables are unusually low, but aren't affecting the idle.
The PE delay is still set at 3 seconds. That's why it's a slug until it hits higher rpm and the PE mode is activated.
The min airflow table will likely need to be increased a bit more as well.

Load this one and see if it helps.

Burban cat del kw mod.hpt

Thank you for taking the time to help me out. I will give this a try tonight or tomorrow and see what happens.
It is also a great learning opportunity for me by comparing the tunes and understanding the changes you made and their effect.

[Homeless]

Kevin
I just now uploaded the tune you sent. It now shifts to reverse without dieing! It also ran much smoother and didn't seem to "labor" as much. Very reminiscent of adding timing to my old 350 race engine LOL

My only concern is that at 1500 (+or-) it will ping pretty noticeable when putting it under a light load, like a small grade over an overpass, in 4th gear and /or torque lock up. My son was working on that so that is probably why the timing tables were a bit low? I specifically made note that I was at 1600rpm and at 50mph if that helps when looking at the scan

Since I did not raise the compression or do anything other than boring .30 over, I dont know why it wants to ping since it didn't before rebuilding the engine. I am running regular octane, can't afford to run high octane without a bank loan LOL

I am attaching two scans, one is the cold start tonight before changing the tune, the other is a larger scan after uploading your changes. If I can resolve the pinging, It I am happy with it.
I appreciate you taking the time to help me out, your tune adjustments have worked wonders!cold start with steve cat del tune.hplcold start with modified kw cat del tune.hpl

[5FDP]

You aren't logging knock retard in the logs, are you sure it has ping/knock?

Add knock retard to your future logs.

It really shouldn't knock at low load rpm in 4th gear. And for what it's worth, you will hear a lot of extra noises from the exhaust with gutted cats. The rasp/drone/pops will now be heard a lot clearer.

[Homeless]

You aren't logging knock retard in the logs, are you sure it has ping/knock?

Add knock retard to your future logs.

It really shouldn't knock at low load rpm in 4th gear. And for what it's worth, you will hear a lot of extra noises from the exhaust with gutted cats. The rasp/drone/pops will now be heard a lot clearer.

Thanks for the feedback.

I am sure it is ping / knock The exhaust has been on the vehicle for a year now so I am used to how it sounds but thanks for asking me to clarify.

I have added Knock retard as you requested then ran another scan this afternoon. I left work and as I drove away under light throttle, it surged about 3 times then was ok the rest of the 1/4 mile to a stop sign. When I let off the accelerator to stop, the engine died which you can see on the attached scan. It turned over for about 2 seconds before it re-fired and was ok the rest of the scan which is about 13 minutes.

One thing I have noticed is that it does not ping until it gets near operating temp. When it is about 1/2 way to 210 degrees', it does not ping but as soon as it gets to about 200, it is very noticeable when using about 1/4 throttle. Once it comes out of torque lock, it gets much better which makes sense because the rpm's increased and was not under the same load.

I am guessing that it needs to pull some timing out during this ping period but as I monitored it, I did not see that happening.
Otherwise, it really runs much better if I can address the ping.

I have attached a scan for review should anyone want to look at it.

Thanks for your help, I hope I am providing good feedback and not being a pain to everyone.

[Homeless]

Can someone point me in the right direction to pull some timing out when the engine starts to ping? What areas do I need to make changes and I will give it a try
Thanks

[kevin87turbot]

Give this one a try and see how it performs. This will help with the KR/detonation.
Burban cat del kw mod 2.hpt

[Homeless]

Thank you Kevin, I will load it tomorrow before I head to work

[JustinRaney]

Found The Pics

9856ba80-9c10-4b1b-bd7a-cc5a1e641fca.jpg

245203af-e6d6-4b4c-a058-c23923a222db.jpg

So the whole intake valve seat dropped into the engine and separated from the aluminum head and smashed between the valve crushing it into pieces kind of like a ring toss? The valve seat on the aluminum head is made of a different metal then the head just regular steel or special type of steel? How many miles did the engine have and what usually causes this? May i ask how you dropped valves before was that due to broken valve springs or something wrong/bad valves? What were the cases of dropped valves i see it had 234k i guess thats alot of miles to not have the heads redone.

[Homeless]

So the whole intake valve seat dropped into the engine and separated from the aluminum head and smashed between the valve crushing it into pieces kind of like a ring toss? The valve seat on the aluminum head is made of a different metal then the head just regular steel or special type of steel? How many miles did the engine have and what usually causes this? May i ask how you dropped valves before was that due to broken valve springs or something wrong/bad valves? What were the cases of dropped valves i see it had 234k i guess thats alot of miles to not have the heads redone.

I am not sure of the process on valve seats (hardened steel) and installed in an aluminum head. The two metals have a different expansion rate so there must be something different when installed in an aluminum head vs a steel head. This is the first time I have had a seat fail. The engine had 234K on it.

I have dropped a valve several years ago in my small block Chevy engine. we had just finished a caution and were picking up the pace to take the green flag again, the engine took off ok then white smoke everywhere and it was over. I found that the head of the valve separated from the stem. It was a tired motor so I got my use out of it

[bcperformance]

Have you ever overheated it? I had a 6.2 that had the same issue. I bought it that way. I was told that it must have overheated at some point.

[Homeless]

Have you ever overheated it? I had a 6.2 that had the same issue. I bought it that way. I was told that it must have overheated at some point.

No this was a one owner and I know the people that had the truck since it was new.
I guess It was just one of those things that failed

[Getch]

add at least 5 deg to your max knock retard table from 500 to 2500 rpm. your vve table looks rough and your maf scale is not smooth. you need more tuning. It takes a while you will get there.

[Getch]

also add 100 ftlb torque to your virtual torque table.

[Getch]

put at least 4000 rpm in your pe not 0 . get the wide band hooked up and go tunning.

[Homeless]

add at least 5 deg to your max knock retard table from 500 to 2500 rpm. your vve table looks rough and your maf scale is not smooth. you need more tuning. It takes a while you will get there.

Thanks for your advice

I am a real rookie and Not sure exactly where to make these changes. I am in the tune under engine/retard/max knock retard vs RPM vs MAP.
Is this what you are referring to regarding the knock retard?

Dont know where the VVE is but I will put some time aside to learn more about the tuner. I just installed an AEM 30-300 wideband system and am using lambda. The Gauge shows the number 1 and fluctuates just a little either direction which I believe is normal.
For some reason, I cannot get the tune software to see the wideband. I am using a serial connection and followed the instructions. I added a DB9 connector and ensured the wiring was correct by Ohm-ing from the harness thru the cable to be sure the data (blue) was on pin 2 and the (black) ground was on pin 5.

I am using a quality Serial to USB converter "Digi-Edgeport/1" and I tie the converter and the MPVI2+ together using a USB hub. All the other data is there but when I add the wideband, the channels get greyed out and a red line thru the icon. I posted a picture below

Thanks for all your help!