[KingLT1]

Originally Posted by ZL1_1LE

I'm trying to grasp timing/boost etc since I don't know much about tuning these cars. If that is the case and you don't get much gain in going higher in timing then why would socal be running so much for little gain?

He likely didn't know any better. Most enthusiasts don't understand tuning and what is and is not safe. That is what they hire a tuner for. Keep in mind it's only seeing that timing in the most unicorn conditions. Some tuners will put all the timing in the base high-octane table then be very aggressive with timing modifier tables such as the IAT spark table. This is a good method to get a high dyno number from a cold pull that you will never see in real world use, but it's great for bragging at cars and coffee. I don't prefer to tune that way. I am not saying it's right or wrong, but I just prefer to put the max safe timing in an engine over a broad range of conditions (hot on the street) and be more conservative with the IAT spark retard. I don't like to see knock in logs.

Fwiw, I am not putting Gabe on blast. He is a very nice guy.

[jlaudio11]

Wow so much timing, I'm over here @ 15 degrees on 15lbs of boost

[2023_ZL1-AUTO]

So, not sure this is helpful in explaining the boost vs spark: But, I looked at several of my log files from this past summer, for when the Spark Adv and Boost were in combination both at the highest values. These are two I found quickly. I didn't look at all my log files obviously, but most recent once from this past summer. Hope it helps to visually explain:

[KingLT1]

Originally Posted by jlaudio11

Wow so much timing, I'm over here @ 15 degrees on 15lbs of boost

Pump gas or E85? Massive difference for sure. I have tuned LT4 cars that wouldn't tolerate more than 17 degrees on pump but would take all the timing you wanted to give it on E60. I just don't like to go above 24-25 degrees on E for safety margin. In some cases that can leave 15-20whp on the table vs 27-28 but I don't like to tune cars on the edge...especially those that I don't know personally. Now if you want to tune your own shit and you got 40k on the line in a grudge race. Then yeah full send!

Originally Posted by 2023_ZL1-AUTO

So, not sure this is helpful in explaining the boost vs spark: But, I looked at several of my log files from this past summer, for when the Spark Adv and Boost were in combination both at the highest values. These are two I found quickly. I didn't look at all my log files obviously, but most recent once from this past summer. Hope it helps to visually explain:

This difference in your timing is related to temperature not boost. One pull was a lot cooler than the other.

[ZL1_1LE]

Originally Posted by KingLT1

Pump gas or E85? Massive difference for sure. I have tuned LT4 cars that wouldn't tolerate more than 17 degrees on pump but would take all the timing you wanted to give it on E60. I just don't like to go above 24-25 degrees on E for safety margin. In some cases that can leave 15-20whp on the table vs 27-28 but I don't like to tune cars on the edge...especially those that I don't know personally. Now if you want to tune your own shit and you got 40k on the line in a grudge race. Then yeah full send!



This difference in your timing is related to temperature not boost. One pull was a lot cooler than the other.

Wow, that's a good catch, didn't think the weather could have that much difference on a tune. Seems you're doing right by not putting cars you tune near the "edge" as you referenced....so much to learn lol.

Originally Posted by KingLT1

He likely didn't know any better. Most enthusiasts don't understand tuning and what is and is not safe. That is what they hire a tuner for. Keep in mind it's only seeing that timing in the most unicorn conditions. Some tuners will put all the timing in the base high-octane table then be very aggressive with timing modifier tables such as the IAT spark table. This is a good method to get a high dyno number from a cold pull that you will never see in real world use, but it's great for bragging at cars and coffee. I don't prefer to tune that way. I am not saying it's right or wrong, but I just prefer to put the max safe timing in an engine over a broad range of conditions (hot on the street) and be more conservative with the IAT spark retard. I don't like to see knock in logs.

Fwiw, I am not putting Gabe on blast. He is a very nice guy.

You can be a nice guy and not know how to tune, or know what is safe and what isn't lol, not sure why everyone has to sugar coat everything these days.

[ZLRob]

Originally Posted by Joshinator99

Nothing to do with knock, everything to do with bottom end longevity. Since I doubt your power gain was much over 25/26 it’s just more stress on the bottom end for little gain.

When you talk about bottom end longevity, are you talking about rod bearings and such, or the actual rods and pistons?

When I did my build I had been running that much timing for quite a while and still messing with other things in the tune. I went over pretty much everything because if you got the engine stripped down to the block you might as well make sure all of the vital bottom end components are clean and I never saw a single issue worth of stress down there. It was all actually really clean and intact.

Originally Posted by KingLT1

Your car isn't 1100whp either. Fun fact, cylinder pressure / temperature rises as you make more power. Last fact, an engine running E85 won't KR easily, which makes it easier to over time an engine. Also, I am not saying you are running too much timing with your current setup, just have to consider all the variables. I know there are plenty of Sub 900whp LT4 cars out there running 26-28 degrees on E85.

Good call. I didn't consider rising cylinder pressure as the subsequent result of more power than before.

[KingLT1]

Originally Posted by ZL1_1LE

Wow, that's a good catch, didn't think the weather could have that much difference on a tune. Seems you're doing right by not putting cars you tune near the "edge" as you referenced....so much to learn lol.



You can be a nice guy and not know how to tune, or know what is safe and what isn't lol, not sure why everyone has to sugar coat everything these days.

Stock LT4 tune pulls timing around 132 degrees on the IAT2 / MAT. Looking at his MAT, it shows 56 Celsius on the pull with less timing, that is 132f, so IAT table is likely still oem and pulling 2 degrees.

Truth!!

[ZL14ever]

Here is my silly $0.02 to throw into the mix

93 oct Pump Gas: Boost+timing = 30 (knock dependent)

Race Gas/E60+:Boost+Timing = 40

Ignite Red/One Ethanol R: Boost+Timing = 45

[JSH]

Originally Posted by ZL14ever

Here is my silly $0.02 to throw into the mix

93 oct Pump Gas: Boost+timing = 30 (knock dependent)

Race Gas/E60+:Boost+Timing = 40

Ignite Red/One Ethanol R: Boost+Timing = 45

100 oct + 20# + advance = 42/44


100 oct + 20# + advance + meth = 43/45

[jlaudio11]

Originally Posted by KingLT1

Pump gas or E85? Massive difference for sure. I have tuned LT4 cars that wouldn't tolerate more than 17 degrees on pump but would take all the timing you wanted to give it on E60. I just don't like to go above 24-25 degrees on E for safety margin. In some cases that can leave 15-20whp on the table vs 27-28 but I don't like to tune cars on the edge...especially those that I don't know personally. Now if you want to tune your own shit and you got 40k on the line in a grudge race. Then yeah full send!



This difference in your timing is related to temperature not boost. One pull was a lot cooler than the other.

That is on E85. Also an LT1 based engine with only a little less static compression than stock but still higher than LT4.

[Megahurtz]

Timing depends on many factors. It certainly doesn't make any sense to run no more than 2 degrees more than your boost level. Sounds like this person was just making stuff up to keep someone from asking too many questions.

[18.2SS.1LE]

Back on the old turbo Honda stuff, we used to pull around a degree of timing per pound of boost.

[JSH]

Originally Posted by Megahurtz

Timing depends on many factors. It certainly doesn't make any sense to run no more than 2 degrees more than your boost level. Sounds like this person was just making stuff up to keep someone from asking too many questions.

That could be. He's very conservative and has told me repeatedly that he doesn't want me to punch another head gasket which appears to be his number one priority.

So far the car's had advance minus boost of +2, + 3 and +4 at 6000-8000 DA

[JSH]

Originally Posted by 18.2SS.1LE

Back on the old turbo Honda stuff, we used to pull around a degree of timing per pound of boost.

1:1? For example, 30 lb of boost and 30° of advance?