So I swapped my JLT CAI back with the stock one today...

[SensesFail]

And now I have consistent short fuel trims and get negative and no knock at every part throttle. My intake temps are better too, they don’t get hot as fast. I don’t drive on the highway often at all, I’m mostly stop and go and the heat soak on a mid Florida day SUCKED for my timing. The engine doesn’t have that cool tone anymore but I’m happy with the trade off. Has anybody else reverted back to stock from their tuned CAI’s?

Sponsored

 

[Mdtaylorjr]

Yep recently took the entire manifold, TB, and CAI off and returned to stock tune so that I could get better mileage and be able to run 87 again since prices are so high. The only mod left is the long tubes and cat back and the stock tune seems to be handling that pretty well.

 

[Jackson1320]

If it’s a 2018+ the cai is very good if it is older then get a 2018+ If you was lower iat run a closed filter system always

 

[Andrew@Lethal]

And now I have consistent short fuel trims and get negative and no knock at every part throttle. My intake temps are better too, they don’t get hot as fast. I don’t drive on the highway often at all, I’m mostly stop and go and the heat soak on a mid Florida day SUCKED for my timing. The engine doesn’t have that cool tone anymore but I’m happy with the trade off. Has anybody else reverted back to stock from their tuned CAI’s?

The stock air box is a well designed intake. It's a true forced induction set up. The only thing that makes it restrictive is the stock paper air filter. If you replace with a K&N or washable filter you will notice some gains because of the better breathability. Check out our options here at www.lethalperformance.com! replacement-air-filters-1

 

[SensesFail]

The stock air box is a well designed intake. It's a true forced induction set up. The only thing that makes it restrictive is the stock paper air filter. If you replace with a K&N or washable filter you will notice some gains because of the better breathability. Check out our options here at www.lethalperformance.com! replacement-air-filters-1

Stupid question but, will I need a tune revision even for the slight increase of airflow because of this?

 

[Andrew@Lethal]

Stupid question but, will I need a tune revision even for the slight increase of airflow because of this?

Negative! Drop one in and enjoy!

 

[cactus_kid]

I truly wished I'd have not changed either. Went back to the stock intake and removed my tune. Personally, the car feels better. IAT's came down as noted and, as like the op, I can run 87 w/o issue. Even here in TX, 93 is already over $4.00 a gallon in many places. And it sure isn't going down any time soon.

 

[jmeiers]

E85 is cheaper than 87. Less mileage, but more power and doesn't smell like shit.

 

[cactus_kid]

By a few cents only here in TX. Worse, for being an oil state, E85 is not that prevalent outside the big metro areas. Plus, I don't want the tune in the car. Be nice if it was flex fuel from the factory. I'd run it.

 

[cmxPPL219]

The stock air box is a well designed intake. It's a true forced induction set up. The only thing that makes it restrictive is the stock paper air filter. If you replace with a K&N or washable filter you will notice some gains because of the better breathability. Check out our options here at www.lethalperformance.com! replacement-air-filters-1

Yup, Andrew is right here with these concise points.

The stock intake system from 15-17 is very good, and 18+ slightly better still. As Andrew suggested, the oem setup is a true technical "cold air intake" because of how it takes the air in, despite how it looks, with no aftmkt-style piping look. (Most oem intake systems from any mfr are very very good nowadays, they don't rob performance like they used to - it's not like before, where the technology and understanding limited the ability for engineers to balance sound, resonance, performance, fuel eco., etc., and the result was performance took a back seat.) What does limit the OEM system is what Andrew mentioned, filter type but also filter size/surface area.
The oems obviously want to engineer the system to account for all kinds of conditions and weather, so outright performance, of course, will take some backseat, even today, as it goes without saying.

Afmkt setups on this car are often labelled Cold Air Intakes, but are actually like a semi-warm air intake (CAI vs WAI in the Afmkt world) because it still has the oem snorkel, but the filter element is open.
There is no problem with this sort of setup, provided that you:
- Have a tune, ideally
- Do not sit in a lot of stop-and-go or constant low speed driving (similar to what OP is experiencing) which causes the heat soak and increased IATs, which can happen tune or no tune

The reason the GT350 has an open-style intake that mimics the afmkt cold air setups, is this model was built with the intention of being very track-focused. So, despite the GT350 ECU calibration built around that open-style intake, you still get the heat soak and IAT issues in situations where you don't constantly move.

With the GT500, they added a lid to an otherwise "identical-looking" to GT350 intake setup, probably due to the immense heat the FI 5.2 produces.

(FWIW, I installed the FP 18+ GT calibration kit which includes the open-element box and a mild FP tune, and in my driving conditions, it's a noticeable and useable improvement over stock, expecially in lower temps. If I was stop and go, I would have never installed this kit)

TL;DR:
There is value in aftermarket cold air intakes, but they are not ideal in many conditions, and can actually rob you of performance, compared to the stock intake - of which on the S550s, they are very well designed for an oem intake system.

 

[SensesFail]

Yup, Andrew is right here with these concise points.

The stock intake system from 15-17 is very good, and 18+ slightly better still. As Andrew suggested, the oem setup is a true technical "cold air intake" because of how it takes the air in, despite how it looks, with no aftmkt-style piping look. (Most oem intake systems from any mfr are very very good nowadays, they don't rob performance like they used to - it's not like before, where the technology and understanding limited the ability for engineers to balance sound, resonance, performance, fuel eco., etc., and the result was performance took a back seat.) What does limit the OEM system is what Andrew mentioned, filter type but also filter size/surface area.
The oems obviously want to engineer the system to account for all kinds of conditions and weather, so outright performance, of course, will take some backseat, even today, as it goes without saying.

Afmkt setups on this car are often labelled Cold Air Intakes, but are actually like a semi-warm air intake (CAI vs WAI in the Afmkt world) because it still has the oem snorkel, but the filter element is open.
There is no problem with this sort of setup, provided that you:
- Have a tune, ideally
- Do not sit in a lot of stop-and-go or constant low speed driving (similar to what OP is experiencing) which causes the heat soak and increased IATs, which can happen tune or no tune

The reason the GT350 has an open-style intake that mimics the afmkt cold air setups, is this model was built with the intention of being very track-focused. So, despite the GT350 ECU tune built around that open-style intake, you still get the heat soak and IAT issues in situations where you don't constantly move.

With the GT500, they added a lid to an otherwise "identical-looking" to GT350 intake setup, probably due to the immense heat the FI 5.2 produces.

(FWIW, I installed the FP 18+ GT calibration kit which includes the open-element box and a mild FP tune, and in my driving conditions, it's a noticeable and useable improvement over stock, expecially in lower temps. If i was stop and go, I would have never installed this kit)

TL;DR:
There is value in aftermarket cold air intakes, but they are not ideal in many conditions, and can actually rob you of performance, compared to the stock intake - of which on the S550s, they are very well designed for an oem intake system.

Perfectly said, thank you.

 

[AZ18yote]

Perfectly said, thank you.

Exactly why keeping stock cai and a high flow filter is the optimal way to go. Especially in hotter climates keeps iats down, provides smoother maf curve as well.

 

[Jhonda]

Next month at rockingham I may test my new jlt tuned on e85 vs my sealed injen intake on e85 if I get a chance. I will post results

 

[SensesFail]

Exactly why keeping stock cai and a high flow filter is the optimal way to go. Especially in hotter climates keeps iats down, provides smoother maf curve as well.

I love this community, there are such insightful people here that I'd have

Next month at rockingham I may test my new jlt tuned on e85 vs my sealed injen intake on e85 if I get a chance. I will post results

please and thank you

Sponsored