Any way to make 2014 Silverado 5.3 idle a little louder?

[dylan.pwilson]

I?ve gone from a simple muffler/resonator delete to a full cat less true dual exhaust but it sounds like a type writer while idling.

Is there anything I can do to increase the volume of sound besides raising the idle rpm?

I know idling up would help but even with a full true dual exhaust, no cats, no mufflers it still doesn?t seem to have any kind of exhaust note at idle.

I am now back to having cats on and the exhaust back to one pipe out the back like they come factory, (straight from the flex pipe back) and I would just like a little more noise when warmed up.

Any advice would help, thanks.

[5FDP]

The stock camshaft is very very mild so it's not going to lope or have any real chop to it.

I have a dynomax catback on my truck and it has to be real quiet outside with minimal background noise to make much noise once it's fully warm and idling at 650-700rpm.

[blindsquirrel]

Buy a Harley, people will definitely take you seriously then.

[TriPinTaZ]

You can jack up the torque model to make it think it needs way less timing at an idle. This will give you a louder idle and then promptly destroy your catalytic converters and overheat everything under your hood when the manifolds start glowing.

You're just going to have to accept that an engine like that isn't going to be loud. And if it sounded like a typewriter while idling, then you likely had an exhaust leak close to the engine.

[5FDP]

The DI trucks are loud at idle though under the hood. The HPFP and injector tick is pretty noticeable.

[nicul15]

You can jack up the torque model to make it think it needs way less timing at an idle. This will give you a louder idle and then promptly destroy your catalytic converters and overheat everything under your hood when the manifolds start glowing.

You're just going to have to accept that an engine like that isn't going to be loud. And if it sounded like a typewriter while idling, then you likely had an exhaust leak close to the engine.

what about ss1le cars? they idle 0-4* factory?

[TriPinTaZ]

what about ss1le cars? they idle 0-4* factory?

I'm not saying you are incorrect, I'm only saying I haven't observed that behavior between 1LE SS's and non 1LE SS's. I'm actually tuning a 2021 1LE SS tonight and I will pay attention to the idle. The 1LE tunes are no different than the regular SS in any way that would affect idle, at least in the tables that are presented in HPTuners. These cars will idle with low timing if they haven't completed the throttle learn procedure after the battery was disconnected or ECU reset. This can sometimes take a few driving cycles to bring the idle timing back into the proper range.

[nicul15]

Interested to see what you find.
Ive logged a new 1le with 600 miles on it and it was idling there. Pretty much matched what people were reporting here. I have a couple of SS cars I tweak. There is definitely something going on there. You can hear it in the idle when they run too.

I think it would be huge to find the tables that are driving this change. As you said they arent showing. Yes we can alter the torque tables, but obv this isn?t the approach the oe took so maybe a better way in there

[tunerpro]

I?ve gone from a simple muffler/resonator delete to a full cat less true dual exhaust but it sounds like a type writer while idling.

Is there anything I can do to increase the volume of sound besides raising the idle rpm?

I know idling up would help but even with a full true dual exhaust, no cats, no mufflers it still doesn?t seem to have any kind of exhaust note at idle.

I am now back to having cats on and the exhaust back to one pipe out the back like they come factory, (straight from the flex pipe back) and I would just like a little more noise when warmed up.

Any advice would help, thanks.

Another possibility is you could change the VVT angle at idle, like the ghost cam people do. This will lower the cylinder pressures and cause the ECM to compensate by opening the throttle more. If you decide to do this, however, I would definitely put an EGT probe on there and test before / after to make sure you're not causing the cats and other exhaust components to overheat.

[TriPinTaZ]

I can confirm, the 2021 SS 1LE that I tuned does idle with 1-5 degrees of timing. Strange that nowhere in the tune, that we normally manipulate to adjust idle timing, is any different than a standard SS Camaro.

[GHuggins]

I can confirm, the 2021 SS 1LE that I tuned does idle with 1-5 degrees of timing. Strange that nowhere in the tune, that we normally manipulate to adjust idle timing, is any different than a standard SS Camaro.

You mind posting the stock log and tune?

[TriPinTaZ]

Here is the stock file. I don't have a bone stock log on this car but the attached log was the first drive with the base tune for Flex Fuel, Intake and Headers. It was still on 93 pump and timing was pulled at at WOT while dialing in the fueling.


Stock 2021 SS 1LE 6 Speed Manual.hpt
2021 SS 1LE log.hpl

I assume you don't need the final file and log but if you do, email me and I'll send it to you there.

[GHuggins]

Honestly I was more interested in how the factory handled the stock cal and the corresponding log to go with it. Just wanted to reassure and double check the way I was back calculating the torque model for cammed gen 5's since the 1le should have a little routier cam in it. Some of the curvatures are turning out about the same and I was having like low timing issues although mine are running in the 5 to 10 range all whilst trying to make drive-ability smooth. Was honestly a little happy to see this. I just haven't tuned any "new new ones yet".

Was curious of something though with emissions and everything it looks like they would run slightly higher timing at idle if only just a little higher. It also shows misfires only at idle - I assume from the low timing?

[32vape]

About the only way is to pull timing out at idle. You can try pulling some out of the idle areas of the main spark tables or raising the vtt in the idle areas.

The SS 1LE's definitely idle with 10deg less than a regular SS. I have tuned many including my own. They hover around 2 degrees stock. A regular SS around 12. Compare the two tunes though and they're the same. Would be nice to have access to whatever tables are different that HP has not defined. Takes a lot more work to get a big cam in a 1LE to idle correctly. The manual 1LE's also exhibit the timing drop bad while taking off from a stop. The immediate axle torque source will sit at "axle" till about 10mph, then like a light switch change to "none", timing bumps up to the main spark tables and you get a surge of acceleration. You really have to hack up the vtt to get it somewhat better, but then results in a overly sensitive throttle at light loads.

[TriPinTaZ]

Honestly I was more interested in how the factory handled the stock cal and the corresponding log to go with it. Just wanted to reassure and double check the way I was back calculating the torque model for cammed gen 5's since the 1le should have a little routier cam in it. Some of the curvatures are turning out about the same and I was having like low timing issues although mine are running in the 5 to 10 range all whilst trying to make drive-ability smooth. Was honestly a little happy to see this. I just haven't tuned any "new new ones yet".

Was curious of something though with emissions and everything it looks like they would run slightly higher timing at idle if only just a little higher. It also shows misfires only at idle - I assume from the low timing?

In the attached log, I had not touched the Virtual Torque, and the MAF was barely changed so any airmass calculations would be incredibly close. As for the misfires, could be the low spark. I pulled 10 degrees on the first log so I'm sure it wasn't happy but I was getting the fuel in the safe area first thing. I don't think GM advertised the 1LE getting a different cam than the standard SS. But this is quite interesting about the fact it idles with less timing. I wonder what the difference is.

About the only way is to pull timing out at idle. You can try pulling some out of the idle areas of the main spark tables or raising the vtt in the idle areas.

The SS 1LE's definitely idle with 10deg less than a regular SS. I have tuned many including my own. They hover around 2 degrees stock. A regular SS around 12. Compare the two tunes though and they're the same. Would be nice to have access to whatever tables are different that HP has not defined. Takes a lot more work to get a big cam in a 1LE to idle correctly. The manual 1LE's also exhibit the timing drop bad while taking off from a stop. The immediate axle torque source will sit at "axle" till about 10mph, then like a light switch change to "none", timing bumps up to the main spark tables and you get a surge of acceleration. You really have to hack up the vtt to get it somewhat better, but then results in a overly sensitive throttle at light loads.

Yep, I couldn't see anything in the tables exposed by HPTuners that would account for the idle timing change. Maybe it is indeed a mechanical difference somewhere?

[Alvin]

I did a 2020 1LE last week that idled around 5 degrees factory. Just adding to the experiences.

Why would it be a 1LE thing? The engines are the same as far as I know. I wonder if it is just odd coincidence that we've noticed it with 1LEs

[GHuggins]

The engines are apparently the exact same for the ss all the way through the 2ss now. The main mechanical differences are what I assume are a "race clutch" - possibly lighter requiring less torque and free'er flowing exhaust - also technically requiring less torque, which would explain the low timing. Even a 2ss idles with more timing - I tune quite a few of these - just don't see any 1le's around here. I just took for granted that the newer one's were like the older one's that had a different engine option possibility. Show's me to research more.

Anyway, I just wanted a stock log for a stock tune to back calculate and check my pids out on before I dug myself into a deeper hole All of my personal stock tunes I've done, I've never bothered saving any stock logs to reverify with...

[32vape]

Engine mechanicals and clutch are all the same SS vs. 1LE. Really the only difference between the two cars driveline wise is the rear end. The 1LE's have the same elsd the ZL1's have. Not sure how that would tie into the idle torque. It could be too that it was just a different engineering team on the 1LE calibration and they came up with slightly different idle mapping. There still had to be some tables not defined that would explain it.

[nicul15]

This is accurate.

I believe the difference here could lead us to influential tables and be very beneficial

[GHuggins]

Well, she does have the same clutch at least as far as gm performance list it. It does have free'er flowing exhaust from factory - only thing other than rearend or trans gearing ratio's listed as being different as far as power train goes... Only thing in the tune I can see that's really changed are a few of the idle torque controls, but these only should control surging and then the more important is the higher fuel pressure that it runs on. They shifted the entire axis to make it hit higher pressures sooner. Also appears it's got the ability to run on higher base pressure. Torque models as listed are exactly the same though.

I don't doubt that there are tables missing - there always are...