[Megahurtz]

lol its just money. If it makes you feel better then do it!

It makes sense NPP would potentially add a small amount of HP since with the valves open, the exhaust doesn't have to push through the baffles in the muffler.

Replacing the crush section on a stock LT1 will get you nothing but less money in your wallet and perhaps some clearance issues.

Put a green filter in it, its not expensive. Put the axle back on it and enjoy the sound. The car wont be faster but it will sound better.

[KingLT1]

Are we really arguing power gains from a filter and muffler swap in 2024? If you want to do it, then do it...but it's not gaining you shit for power. These cars were optimized a lot more than previous generations to make the power they already do in stock form.

The best bang for buck on this platform is a flex sensor and tune. E85 is worth about 25whp gain. Then you can either Port the stock manifold or throw a LT2 and 95mm tb on while you are at it... there is 40-45whp worth of power total and you compromised nothing in terms of how the car sounds or behaves.

[Joshinator99]

Originally Posted by KingLT1

Are we really arguing power gains from a filter and muffler swap in 2024? If you want to do it, then do it...but it's not gaining you shit for power. These cars were optimized a lot more than previous generations to make the power they already do in stock form.

The best bang for buck on this platform is a flex sensor and tune. E85 is worth about 25whp gain. Then you can either Port the stock manifold or throw a LT2 and 95mm tb on while you are at it... there is 40-45whp worth of power total and you compromised nothing in terms of how the car sounds or behaves.

[knighti2]

Originally Posted by KingLT1

Are we really arguing power gains from a filter and muffler swap in 2024? If you want to do it, then do it...but it's not gaining you shit for power. These cars were optimized a lot more than previous generations to make the power they already do in stock form.

The best bang for buck on this platform is a flex sensor and tune. E85 is worth about 25whp gain. Then you can either Port the stock manifold or throw a LT2 and 95mm tb on while you are at it... there is 40-45whp worth of power total and you compromised nothing in terms of how the car sounds or behaves.

Some will never listen no matter how many times they are told or had it explained to them.

[ZPirate]

I recently installed a Green filter in my ZL1. I was looking for better air flow from the stock sealed air box. I considered a Rotofab, but ultimately was more concerned with heatsoak than total airflow in my ZL1. I live in an area where highs are typically over 80 degrees approximately half the year and humidity levels are also high. Heatsoak is an issue during this time and I wanted to keep my IATs as close to ambient as possible.

[Joshinator99]

Originally Posted by ZPirate

I recently installed a Green filter in my ZL1. I was looking for better air flow from the stock sealed air box. I considered a Rotofab, but ultimately was more concerned with heatsoak than total airflow in my ZL1. I live in an area where highs are typically over 80 degrees approximately half the year and humidity levels are also high. Heatsoak is an issue during this time and I wanted to keep my IATs as close to ambient as possible.

Total airflow > IAT1 temps

Keep in mind your IAT1 temp is PRE-intercooler. The fastest PD blower Gen6 Camaro (ZL1Atlanta) has a wide open air filter in the engine bay with no shield or baffle whatsoever.

[Megahurtz]

Originally Posted by ZPirate

I recently installed a Green filter in my ZL1. I was looking for better air flow from the stock sealed air box. I considered a Rotofab, but ultimately was more concerned with heatsoak than total airflow in my ZL1. I live in an area where highs are typically over 80 degrees approximately half the year and humidity levels are also high. Heatsoak is an issue during this time and I wanted to keep my IATs as close to ambient as possible.

A green filter and a ported stock TB does gain power on a stock ZL1. Specifically because of the blower.

My personal 2023 ZL1 ran a best 8.83 60-130 draggy when bone stock.
Added a Green Filter and a ported 87mm TB and the car ran a best 8.31s 60-130.
Added my TCM tune and E30 and the car ran a best 7.73 60-130.
Added Headers and E60 and ran a best 7.14 60-130
Added 2.3 Upper and E50 and it ran a best 6.85 60-130. All on the stock airbox with a drop in green filter, my ECU and TCM tuning. Anything past this is going to start being a restriction.

I have a ported blower, Big Gulp and 107mm TB sitting on the shelf but I'm waiting on the DSX port kit to come out. I want to run full E on this car and figured I would do some real world draggy testing on this car compared to my Z06. The goal of this car is to be a full daily driver car that runs full E85 but click off low 6's on stock tires or high 5's on drag radials. My manual Z06 on street tires ran a 6.1 60-130 draggy but it would have been in the 5's easy with traction. I suspect the ZL1 will be the same or better due to the 10 speed even though its 600lb heavier than the Z06.

Anyhow, my point is, the stock airbox is not a restriction on the LT1 in stockish form. If you add headers, LT2 manifold and 95mm TB, Flex fuel, a green filter in the stock airbox is plenty of flow. You will need a tune to optimize timing.

[ctrlz]

If we're talking about 1-2 HP, that has gotta be within the margin of error for any device measuring HP.

Any filter which flows more freely will only do so until it is partially clogged. The "dirt plug" actually makes filtration better, at the expense of flow. There is a continuous tradeoff in the life of a filter. I would not want a free-flowing filter that I kept clean all the time for daily use.

[Evergreen6]

Originally Posted by ctrlz

If we're talking about 1-2 HP, that has gotta be within the margin of error for any device measuring HP.

Any filter which flows more freely will only do so until it is partially clogged. The "dirt plug" actually makes filtration better, at the expense of flow. There is a continuous tradeoff in the life of a filter. I would not want a free-flowing filter that I kept clean all the time for daily use.

No filter probably nets more HP, I mean, why not, it's not like Green or K&N are exceptionally great at actual particulate filtration. Paper media is.

1-2hp isn't going to make a difference for 99% of my spirited leisure driving. Track use, actual competition? Sure. But there are tradeoffs.

[ZPirate]

Originally Posted by Joshinator99

Total airflow > IAT1 temps

Keep in mind your IAT1 temp is PRE-intercooler. The fastest PD blower Gen6 Camaro (ZL1Atlanta) has a wide open air filter in the engine bay with no shield or baffle whatsoever.

I get it. However, at this point my car is basically stock except for the Green filter, the removal of the steel sound plate from inside the supercharger lid and the addition of a coolant reservoir for the intercooler.

[ZPirate]

Originally Posted by Megahurtz

A green filter and a ported stock TB does gain power on a stock ZL1. Specifically because of the blower.

Anyhow, my point is, the stock airbox is not a restriction on the LT1 in stockish form. If you add headers, LT2 manifold and 95mm TB, Flex fuel, a green filter in the stock airbox is plenty of flow. You will need a tune to optimize timing.

That's what my research indicated and why I went with the Green filter over a Rotofab at this point. I'll have to look into the ported stock TB.

[Megahurtz]

Originally Posted by ZPirate

That's what my research indicated and why I went with the Green filter over a Rotofab at this point. I'll have to look into the ported stock TB.

ported stock TB is an easy 10rwhp on an LT4. I showed a 15rwhp gain but I took 5rwhp away as a buffer for dyno error.