[JANNETTYRACING]

Originally Posted by GunMetalGrey

Question Ted, if this is true, how does the LT5 get away with it when hittin a 750hp power level without having LT Headers? I know it has a larger more efficient SC which creates lower IATs compared to spinning a smaller SC faster, does that offset not havin LT headers?
If so I assume it would be even more consistent with the power it creates if LT headers were added to the LT5 as well.

This thread is focused on the LT4 and has no correlation to the LT5, it is an entirely different engine.

[JANNETTYRACING]

Originally Posted by Macaro

Great thread! I can’t believe Ted’s shop is less than an hour from me!

Two easy, and perhaps dumb, questions.

1.) Does a tune void the factory warranty?
2.) Your impressive gains with tune alone were on 100 octane fuel, any idea what they may be on 93 pump gas?

One way or another, we gotta connect Ted, how often are you at Lime Rock? I’m there 10 or more days a year.

Any tune can potentially void a warranty when or if a failure were to occur and the dealer uploads a screen shot of the flash counter.

The delta gains should be the same but you will start as a lower number in my experience 540-550 on 93

Absolutely please feel free to stop in any time and I am always at limerock and Palmer with the BMW club HPDE events.

Aside from power mods we do chassis scaling, alignments, suspension, brakes, wheels tires etc.

We can really dial your car in for you.

Ted.

[staples87]

Originally Posted by Macaro

Great thread! I can’t believe Ted’s shop is less than an hour from me!

Two easy, and perhaps dumb, questions.

1.) Does a tune void the factory warranty?
2.) Your impressive gains with tune alone were on 100 octane fuel, any idea what they may be on 93 pump gas?

One way or another, we gotta connect Ted, how often are you at Lime Rock? I’m there 10 or more days a year.

It will at the very least void the engine part of the powertrain warranty. If anything happens to the motor and they find out it was flashed / tuned they can easily blame any mechanical engine failure on the tune causing the issue.

"Too much timing from the tune, causing detonation and heat to build in the cylinder walls, taking out the piston rings and causing major oil consumption."

This is just an example of an excuse the dealership could use to get out of replacing a new motor under warranty. Whether or not it's true, you'd still have an uphill battle to prove otherwise. If you don't have the funds to fix what's broken then I'd suggest no more than minor bolt-ons. (exhaust or intake).

[GunMetalGrey]

Originally Posted by JANNETTYRACING

This thread is focused on the LT4 and has no correlation to the LT5, it is an entirely different engine.

Didn't realize they were so different, after doing more research and thinking about the impact those differences would make, your response makes sense

[BMWM.D.]

Ted, could you give us more data on the maximum power gains with the headers? There look to be some big gains at say 6500 rpm as the manifold curve noses over. My guess was 40 whp up top, but that was just from trying to read the graph. Thanks

[waterman]

Originally Posted by BMWM.D.

Ted, could you give us more data on the maximum power gains with the headers? There look to be some big gains at say 6500 rpm as the manifold curve noses over. My guess was 40 whp up top, but that was just from trying to read the graph. Thanks

+1. Good eye BMWM.D. I was going to hold off on headers until I saw your manifold comparison thread. 2" seems very restrictive to me.

Ted; My thoughts are to upgrade intake and exhaust in stages to get a few more miles out of my warranty, then JRE tune via HPtuners, with bolt on's in place.

If I can get 40-50 wHP and TQ on race gas without spinning the blower faster, E85 or methanol, I'm extremely interested.

Thanks in advance for your thoughts.

[GunMetalGrey]

Originally Posted by JANNETTYRACING

Gentlemen Thank you all for the great response, this kind of feels like the old days of Gen5 when we would post something and get an overwhelming response.

I have had some time to process the info from the dyno session and I will be adding the results from the CAI and ROTOFAB we did right after that video.

When I look at a calibration and the matching data logs I see that GM is requesting a certain EQ ratio or in layman's terms AFR.

This chart (BELOW) is the AFR request from the stock tune, you take Lambda 1 / this value and get your commanded lambda, for example at the top rpm range you see 1.19 so 1/1.19 = .84 and in the video you see it went all the way down to .72 lambda

If you want to convert lambda to AFR take 14.7/ Lambda value so 14.7/.72 is 10.58 AFR.

I set the commanded Lambda to EQ 1.22 or .82 Lambda or 12.0 AFR which is richer than the .84 or 12.35 that GM was asking for.

We also look at long term fuel trims or LTFT and the goal is to achieve Negative 1-2% and when we go to WOT achieve commanded Lambda.

From my experience GM was very good at MAF calibration on most all of the previous generations and other models.

This model it seems GM Missed the boat and it is Rich Everywhere, by over reporting Air flow which leads to seeing more airflow than expected which in turn causes the throttle closing to control that air flow.

MAF calibration is the single most important part of the tune it affect everything else.

I had to take about 8% out of the whole MAF curve then another 8% up top to get the LTFT and AFR in line with commanded.

The Results of my tuning speak for themselves.

A bad tune from the factory makes me look like a hero LOL.

Ted.

Hi, is that much throttle closure normal in the mid rpm ranges for a ZL1?

How much, if at all, do you think the cold weather and race fuel effected the throttle closure on the baseline runs?

[JANNETTYRACING]

Originally Posted by BMWM.D.

Ted, could you give us more data on the maximum power gains with the headers? There look to be some big gains at say 6500 rpm as the manifold curve noses over. My guess was 40 whp up top, but that was just from trying to read the graph. Thanks

At 6800 there is as much as 55 RWHP gain which further illustrates the restriction the factory manifolds and cats are placing on the engine.

Ted

[JANNETTYRACING]

Originally Posted by waterman

+1. Good eye BMWM.D. I was going to hold off on headers until I saw your manifold comparison thread. 2" seems very restrictive to me.

Ted; My thoughts are to upgrade intake and exhaust in stages to get a few more miles out of my warranty, then JRE tune via HPtuners, with bolt on's in place.

If I can get 40-50 wHP and TQ on race gas without spinning the blower faster, E85 or methanol, I'm extremely interested.

Thanks in advance for your thoughts.

Running 100 octane gasoline definitely will give you at least 40 RWHP base on my testing.

Add a Rotofab and you are there but the tuning is what really unleashes the power as the factory calibration did leave a lot on the table which is out of character for GM.

Ted

[JANNETTYRACING]

Originally Posted by GunMetalGrey

Hi, is that much throttle closure normal in the mid rpm ranges for a ZL1?

How much, if at all, do you think the cold weather and race fuel effected the throttle closure on the baseline runs?

The throttle closure is a result of the calibration for the MAF being off, it reports more Air flow than actual which results in Higher torque reporting than expected so the computer closes the throttle to control torque.

Ted

[bobby35ny]

Originally Posted by JANNETTYRACING

The throttle closure is a result of the calibration for the MAF being off, it reports more Air flow than actual which results in Higher torque reporting than expected so the computer closes the throttle to control torque.

Ted

I wonder if that was done on purpose by GM?
=Bobby

[GunMetalGrey]

Originally Posted by JANNETTYRACING

At 6800 there is as much as 55 RWHP gain which further illustrates the restriction the factory manifolds and cats are placing on the engine.

Ted

So I assume this wouldn’t matter as much for an auto like the A10 since it would shift exactly at 6500rpm and would shift faster?

[Exgermanowner]

I need to ask a real ignorant question Ted.

So if I did all the bolt ons as you did and had the car tuned on 93, would I have to install another tune to take advantage of just changing over to 100 octane fuel or would the system adjust on the fly? I couldn’t afford 100 octane everyday, but have access at the road course pumps. Thanks

[2018ZL1]

Originally Posted by Exgermanowner

I need to ask a real ignorant question Ted.

So if I did all the bolt ons as you did and had the car tuned on 93, would I have to install another tune to take advantage of just changing over to 100 octane fuel or would the system adjust on the fly? I couldn’t afford 100 octane everyday, but have access at the road course pumps. Thanks

The best thing to do would be to install the E85 sensor and that way you have the best of both worlds without having to change the tune! The computer will automatically adjust for either 93 or E85 and I do believe E85 will make as much power as 100. Now if you cant get E85 in your area that would be a problem! Makes things real simple and installing the E85 sensor was really simple!