[Fstlane]

So I've read in several different forums both Camaro and Corvette Where people are claiming you can damage the LT4 by not having a tune. Can someone please explain to me Why and how that happens?
Or is this just another internet rumor?

[DangerZL1]

Headers lean out the A/F ratio too much to be safe. The factory tune can’t compensate for the leaner mixture. It’s not a rumor.

[2023_ZL1-AUTO]

Originally Posted by DangerZL1

Headers lean out the A/F ratio too much to be safe. The factory tune can’t compensate for the leaner mixture. It’s not a rumor.

Agree, with the above. I just went through this on my mods. My ZL1 with no tune was running really lean. So I babied around in it a bit until my tuner and I got hooked up. He took it from there and I'm very happy with my tune. I'd be worried running too lean. I went with the AEM AFR X-Series 30-0300 Gauge to make sure I was data logging the AFR Wide Band data for the tuner to do his magic.

[SJFGTO]

Lean condition caused by headers/no tune is real. Damage usually occurs when you accelerate briskly.

[Fstlane]

Thanks ...did you leave the wide band installed or remove it once the tune was done? I don't care for all the extra gauges so if not needed I would like to remove it until the next tune.

[KingLT1]

I don't believe it will damage the engine on the LT4. The ECM will simply close the throttle with headers and no tune gaining nothing. There is a good chance the car will be slower. These cars are not like modding old school stuff. They have torque-based ECU's that require increasing the systems torque limits when you do mods to make more power. The LT4's also go into RDP mode when running too lean.

[DylansZLE]

I know of at least 2 people that have tracked their ZL1 1LE's with headers and no tune with no issues after 10+ track days.

Not saying it wont damage anything, but it seems there is a safety buffer like mentioned previously with the ECM.

[SJFGTO]

It will create a lean condition that the ecm will not fully adjust for. At a minimum you will never get the bang for the expensive bucks headers will cost, you’ll be leaving HP on the table. At worst, you damage your engine. Why risk it? Everybody knows somebody who flew in the face of reality and had no problems, so for me, personally, I would not assume a risk of damaging my Camaro because a couple other dudes I never heard of did something different.

[Fstlane]

No disagreement on unnecessary risk! But I couldn't resist the urge to go for a 20 minute test ride....nothing radical ....leak testing if you will.
I am also planning to remote tune and want to weigh all the options E 85, CAI . After doing more research it looks like I am going to have to live with pillar gauges for the wideband and ethanol content gauge.

Sorry for the deviation I just want to do the right mods

[Schlok]

Originally Posted by Fstlane

No disagreement on unnecessary risk! But I couldn't resist the urge to go for a 20 minute test ride....nothing radical ....leak testing if you will.
I am also planning to remote tune and want to weigh all the options E 85, CAI . After doing more research it looks like I am going to have to live with pillar gauges for the wideband and ethanol content gauge.

Sorry for the deviation I just want to do the right mods

You are going to need serious fuel upgrades to run full E85. Headers causing the car to run lean is going to exacerbate your E85 fueling ambitions as that requires 'more fuel on top of more fuel' now. The stock fuel system will support some ethanol content but not full on E85. E30 to E40 seems to be about the safe number on the stock fuel system and you'll net around 650 to 660 Whp depending on dyno and your baseline. By no means am I the expert here, just a good student of the forum.

[2023_ZL1-AUTO]

Here is a video that helped me with my pillar gauges install and my thread where I did mine gauges. As far as the flex fuel kit goes. I'm still not sure I have enough pump for much of an e mix. I'd love to get input from someone that has similar mods as I do but also with Flex Fuel kit and see what e-mix they are running.

https://www.camaro6.com/forums/showp...0&postcount=42

https://youtu.be/9-QDneCUzL8

[Katech_Mike]

Originally Posted by KingLT1

I don't believe it will damage the engine on the LT4. The ECM will simply close the throttle with headers and no tune gaining nothing. There is a good chance the car will be slower. These cars are not like modding old school stuff. They have torque-based ECU's that require increasing the systems torque limits when you do mods to make more power. The LT4's also go into RDP mode when running too lean.

Agreed.

I would also say that most home header installs especially when using cheaper headers aren't great. The false knock will beat them into the low octane spark tables half the time.

[NG329]

The distance of the O2 sensors is altered and that affects the calculations in the tune. Unless it is corrected the car will run like crap.

You're spending $2k for headers on a $70k+ car. Why the hell would you skimp on a tune? Pure fuc$kery.

[NG329]

Originally Posted by Katech_Mike

Agreed.

I would also say that most home header installs especially when using cheaper head aren't great. The false knock will beat them into the low octane spark tables half the time.

In addition to the false knock that will surely result from aftermarket headers, you will definitely need to play with the knock sensor settings in the tune. It took a lot of trial and error to get mine dialed in.