Idle/drive transition and bogging with the TC locked

[Quickstop [UK]]

I'm finally driving my truck after 4 years off the road and it's awesome but it could be a lot better.

I'm getting a lot of help with Code59 but for now I have a pretty good Code58 tune that is working well though I have a couple of issues and figured I may as well ask here so maybe someone else can see what I am learning and maybe someone knows the answers

First off, I have a 415 cam and the idle is great at around 950-1000. Yeah, it's faster than stock but it's smooth and I like it. The problem is going from idle to Reverse or to Drive, it bogs ever so slightly when it gets put under load. Where should I be looking to mess with this? Spark advance ramp? It's a pretty fat idle so I don't think fuel is the issue.

Next up, the torque converter locks up like it should but when I give it a little gas, the truck bucks - it feels like if you put a manual into 5th gear when you're trying to pull away from too slow. It doesn't do it with my foot off the gas and the TC disengages if I give it a lot of gas so it's acceleration related, not lockup. The Circle D converter has less than 500 miles on it so I am sure the issue lies in the tune.

It's around 16.0 AFR in cruise so I am leaning (hahaha) on it needing a bit more fuel. Any thoughts? Or do I need more timing here too?

Lastly, I read a really interesting article on Innovate's website - basically saying that rather than making a mixture really rich to avoid knock, retard the timing slightly and leave it a bit more lean to allow the peak cylinder pressure to occur at the same time. I was very curious as the advice here i usually to aim rich and avoid knock but the article contradicted this. Anyone have any thoughts on it?

Spark Timing Myths Debunked - Spark Timing Myths Explained:: Application Notes

I have some false knock to contend with as well - it's pulling timing even at 5 psi. What AFR should I be at around there? 13.5 OK for 5 psi?

This truck wants to go and is finally getting driven and some TLC. Thanks for reading. I'm going to be doing some tuning this week so hope I can report some progress.

Thanks for looking! :tup:

 

[Quickstop [UK]]

Re: Idle/drive transition and bogging with the TC locked

No progress to report - maybe someone can help?

What XDF and ADX file do I need for a Code58 .bin in TP5? I can log the ALDL but I can't get the tracing bubble so I can't work out which cell to adjust and tune the truck.

Is it possible to transfer the tables from Code58 into a code59 bin?

Thanks!

 

[Aeroking]

Re: Idle/drive transition and bogging with the TC locked

I'm finally driving my truck after 4 years off the road and it's awesome but it could be a lot better.

I'm getting a lot of help with Code59 but for now I have a pretty good Code58 tune that is working well though I have a couple of issues and figured I may as well ask here so maybe someone else can see what I am learning and maybe someone knows the answers

First off, I have a 415 cam and the idle is great at around 950-1000. Yeah, it's faster than stock but it's smooth and I like it. The problem is going from idle to Reverse or to Drive, it bogs ever so slightly when it gets put under load. Where should I be looking to mess with this? Spark advance ramp? It's a pretty fat idle so I don't think fuel is the issue.

Next up, the torque converter locks up like it should but when I give it a little gas, the truck bucks - it feels like if you put a manual into 5th gear when you're trying to pull away from too slow. It doesn't do it with my foot off the gas and the TC disengages if I give it a lot of gas so it's acceleration related, not lockup. The Circle D converter has less than 500 miles on it so I am sure the issue lies in the tune.

It's around 16.0 AFR in cruise so I am leaning (hahaha) on it needing a bit more fuel. Any thoughts? Or do I need more timing here too?

Lastly, I read a really interesting article on Innovate's website - basically saying that rather than making a mixture really rich to avoid knock, retard the timing slightly and leave it a bit more lean to allow the peak cylinder pressure to occur at the same time. I was very curious as the advice here i usually to aim rich and avoid knock but the article contradicted this. Anyone have any thoughts on it?

Spark Timing Myths Debunked - Spark Timing Myths Explained:: Application Notes

I have some false knock to contend with as well - it's pulling timing even at 5 psi. What AFR should I be at around there? 13.5 OK for 5 psi?

This truck wants to go and is finally getting driven and some TLC. Thanks for reading. I'm going to be doing some tuning this week so hope I can report some progress.

Thanks for looking! :tup:

Without looking at your datalog, i can make some unprofessional assumptions.

If the truck is bucking under acceleration, i would guess that you are locking the converter too soon. The trans will let the converter lock in 2nd, 3rd, and OD. Just like you mentioned, its like being in 5th gear with low RPMs. Try to set the minimum lockup speed to 40-50mph, and if you can only lockup in OD.

For timing, you can run low 30s for light throttle cruise speeds. This will help throttle response, also it will keep the engine temps down. I would not lean it out to 16 though, 15.5 at the absolute leanest. Cruising at 15.0 will give you great fuel mileage. But keep the 15.0 at your low kpa and low TPS, when you start to give it throttle, bring it right back into the high 13s. Also, you can keep the AFR in the 13s when you are spooling and under low boost, but once you get over 5psi, start to ramp the AFR down to the 11s. You can do the same with timing. The engine just before boost is similar to a N/A 4.3, so you can hold the timing high during boost transition. That makes a world of difference in spool-up. With the 100kpa timing in the high 20s the engine should seamlessly transition into boost, it shouldn't be an abrupt pause.

For the idle on your VE & spark tables you will probably end up with a "hole" where the numbers are low right at idle rpms. Then the numbers jump up as soon as you give it throttle. This is fine, and the hole will help keep the RPMs from wandering. So don't try to smooth the graph too much at idle speed. If it bogs when you first give it throttle, adjust the throttle transient tables to add fuel when TPS rate changes.

Again, just my non-pro opinion

 

[RealFastV6]

Idle/drive transition and bogging with the TC locked

First off, I have a 415 cam and the idle is great at around 950-1000. Yeah, it's faster than stock but it's smooth and I like it. The problem is going from idle to Reverse or to Drive, it bogs ever so slightly when it gets put under load. Where should I be looking to mess with this? Spark advance ramp? It's a pretty fat idle so I don't think fuel is the issue.

Tip in stumble (what you're describing) is typically caused by the fueling not keeping up with the immediate increase in air from the throttle body when it gasps for a big breath.

A map sensor can't react fast enough to increase fueling under the normal VE (volumetric efficiency) table math - so the AE (acceleration enrichment) tables are there to compensate for quick TPS or MAP changes.

During tuning it's usually fixed in AE TPS Rate of Change. No idea what it's called specifically on Code 58/59. Add fuel there until it smooths out. You'll need to fix it at a light blip of the throttle and then a heavy blip of the throttle.

Hope that helps anybody reading.


Sent from my iPhone using Tapatalk

 

[Quickstop [UK]]

Re: Idle/drive transition and bogging with the TC locked

Thanks guys - appreciate the input. I have a slightly more updated tune now and the truck drives a lot better. The bucking from the TC has gone and now the truck pulls like a freight train with the TC locked in 4th gear. At around 5-7 psi, it accelerates from 70 mph like it's pulling away from a stop sign. The pull is really strong and passing vehicles is great fun. I accelerate to dangerous speed very quickly. It's a grin-inducing ride!

The table is a bit fatter in cruise now but probably a bit too much. I still have what I believe is false knock as the AFRS are in the low 12s at 5psi, the IC is working well and the engine sounds great.

I did a boost launch and my controller isn't set up at all. The Greddy is a bit weird. I sort of wish I just had a manual with and adjustable. Greddy has too many options. That said, 10psi and the launch is hard. The truck feels strong. I really want to put it on a dyno and see where it's at, especially in light of the article about pulling timing vs. adding fuel.

I can also see myself needing bigger injectors and a Steve Morria cam in the future.

Just to recap, my Dad bought the truck in 1992 and owned it for 8 years. He had a lot of issues in KSA when we had it but when I took him for a ride last night, he said it had never accelerated so fast. I guess I am slowly getting there!