Cold Air Intake
Racer
Joined: Apr 2005
Posts: 492
Likes: 10
From: Sacramento California
Safety Car
Joined: Oct 2003
Posts: 3,597
Likes: 101
From: TN PA
CI 5-6-7-8-9-10-11 Vet
And fortunately, my experience thus far is the same as GSM - took 'er out after work to battle test - idles just as smooth as ever - no surging or bucking whatsoever. And when I stomped the gas from a stop in a remote area, it felt like there was more fishtailing than I've experienced before. Anyway, hopefully I can get some strip time in before summer hits and this mod will prove that it is worth the time and effort. But until then, I'm just happy she still runs perfect
I have just removed the Halltech and gone back to the factory set up. But, I have cut the Beehive to fit the stock intake. I havent had a chance to drive it yet to see how this will work with the shroud propped open.
I'll post some photos tomorrow on this mod....
Team Owner
Joined: Sep 1999
Posts: 41,732
Likes: 1,718
From: Springfield MO
On my car the bucking happens at light throttle crusing when I have the shroud propped open. Mostly at highway speeds. The bucking happen less with the Halltech than with the stock intake, but still did it some.
I have just removed the Halltech and gone back to the factory set up. But, I have cut the Beehive to fit the stock intake. I havent had a chance to drive it yet to see how this will work with the shroud propped open.
I'll post some photos tomorrow on this mod....
I have just removed the Halltech and gone back to the factory set up. But, I have cut the Beehive to fit the stock intake. I havent had a chance to drive it yet to see how this will work with the shroud propped open.
I'll post some photos tomorrow on this mod....
As for the Halltech bucking less than the stock breather with the open shroud, this could be because the closed bottom of the Halltech filter element directs the air to the sides of the filter. On the stock breather, the air rushing in at highway speeds from a popped shroud, hits the face of the filter element directly and doesn't have a chance to get laminar air flow before passing across the MAF.
I have the Vette-Air scoop, that really forces the air to hit the face of the stock filter element with significant force to cause surging/bucking.
I had to install a flat diffuser panel on the discharge side of the scoop to prevent the air being discharged from the scoop from hitting the face of the stock breather directly.
Team Owner
Joined: Feb 2001
Posts: 27,254
Likes: 136
From: Short Hills, NJ
A good tuner that is well versed in the use of HP Tuners and/or EFI Live should be certainly able to remedy any potential surging/bucking/idle issues.
Burning Brakes
Joined: Nov 2012
Posts: 1,049
Likes: 1
From: Wisconsin
Adding that Vette-Air scoop is the ONLY way I would ever use a CAI other than the Vararam (my first choice otherwise) as it definitely compliments those units which don't have a large scoop grabbing cooler air way out in front by the grill (such as a Vararam) like that.
A good tuner that is well versed in the use of HP Tuners and/or EFI Live should be certainly able to remedy any potential surging/bucking/idle issues.
A good tuner that is well versed in the use of HP Tuners and/or EFI Live should be certainly able to remedy any potential surging/bucking/idle issues.
Safety Car
Joined: Oct 2003
Posts: 3,597
Likes: 101
From: TN PA
CI 5-6-7-8-9-10-11 Vet
Correct, stock filter.. The propped shroud works perfect at WOT..
I removed the Halltech but kept the Beehive. It took a little cutting to get it to fit. If you seen my above post both my 11 Camaro SS and my 08 Vette ran slower at the dragstrip with the aftermarket CAI's. Both cars had stock tunes...
Note the rubber blocks holding the shroud open... They are coil spring spacers.. Still havent had a chance to drive the vette with the propped shroud on the stock intake with the beehive
Halltech Beehive modified to fit the stock intake....
I removed the Halltech but kept the Beehive. It took a little cutting to get it to fit. If you seen my above post both my 11 Camaro SS and my 08 Vette ran slower at the dragstrip with the aftermarket CAI's. Both cars had stock tunes...
Note the rubber blocks holding the shroud open... They are coil spring spacers.. Still havent had a chance to drive the vette with the propped shroud on the stock intake with the beehive
Halltech Beehive modified to fit the stock intake....
Team Owner
Joined: Sep 1999
Posts: 41,732
Likes: 1,718
From: Springfield MO
Correct, stock filter.. The propped shroud works perfect at WOT..
I removed the Halltech but kept the Beehive. It took a little cutting to get it to fit. If you seen my above post both my 11 Camaro SS and my 08 Vette ran slower at the dragstrip with the aftermarket CAI's. Both cars had stock tunes...
Note the rubber blocks holding the shroud open... They are coil spring spacers.. Still havent had a chance to drive the vette with the propped shroud on the stock intake with the beehive
Halltech Beehive modified to fit the stock intake....
I removed the Halltech but kept the Beehive. It took a little cutting to get it to fit. If you seen my above post both my 11 Camaro SS and my 08 Vette ran slower at the dragstrip with the aftermarket CAI's. Both cars had stock tunes...
Note the rubber blocks holding the shroud open... They are coil spring spacers.. Still havent had a chance to drive the vette with the propped shroud on the stock intake with the beehive
Halltech Beehive modified to fit the stock intake....
Whereas you are using the Halltech beehive, I'm using the two wings from a Airaid unit to keep hot air from spilling over into the air breather compartment from the engine compartment when the car is not moving.
Safety Car
Joined: Oct 2003
Posts: 3,597
Likes: 101
From: TN PA
CI 5-6-7-8-9-10-11 Vet
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Safety Car
Joined: Nov 2007
Posts: 4,435
Likes: 874
From: Bay Area CA
Interesting enough, I had the oem air intake and Halltech MF 103 both with the Beehive shroud ( custom cut one for the oem air intake) and opened the bottom ends of the shroud for cold air with no surging. However, once the bottom center portion of the shroud started to open up (retainers loosened up) I felt a slight surge at cruise speeds only, i.e. 60 mph on freeway feathering the gas. It was very slight, but I noticed it. This occurred with the oem air intake, Halltech air intake, oem tune and custom tune. Once the center shroud was secured, the slight surge was gone. Interesting to read some do and do not experience this!
One thing to look at with the open front portion of the shroud is your fuel trims and how much correction is being made while driving. I bet some of the turbulent air is causing the fuel trims some havoc trying to stabilize adjustments in fuel metering.
One thing to look at with the open front portion of the shroud is your fuel trims and how much correction is being made while driving. I bet some of the turbulent air is causing the fuel trims some havoc trying to stabilize adjustments in fuel metering.
Safety Car
Joined: Nov 2007
Posts: 4,435
Likes: 874
From: Bay Area CA
Mike'sLS3, that's good info...thanks. Just to clarify, when you say 'opened up the bottom ends of the shroud'..I assume it's those 2 small 1"x3" plastic lips per Halltech's website? I think he refers to them as ram air induction ports. I'm considering removing those on my LS3 radiator shroud & am running the stock intake/Donaldson filter.
Burning Brakes
Joined: Nov 2012
Posts: 1,049
Likes: 1
From: Wisconsin
Mike'sLS3, that's good info...thanks. Just to clarify, when you say 'opened up the bottom ends of the shroud'..I assume it's those 2 small 1"x3" plastic lips per Halltech's website? I think he refers to them as ram air induction ports. I'm considering removing those on my LS3 radiator shroud & am running the stock intake/Donaldson filter.
Sorry, just so I understand (because the Halltech installation instructions are not clear to me), in the first photo of the "Beehive Install with Optional Cold Air Ports" instructions, are the two blue areas that Jim Hall is saying to "cut out" the same as the "Ram Air Induction Ports" shown in photograph four?
Thanks!
Safety Car
Joined: Nov 2007
Posts: 4,435
Likes: 874
From: Bay Area CA
Bed:
Sorry, just so I understand (because the Halltech installation instructions are not clear to me), in the first photo of the "Beehive Install with Optional Cold Air Ports" instructions, are the two blue areas that Jim Hall is saying to "cut out" the same as the "Ram Air Induction Ports" shown in photograph four?
Thanks!
Sorry, just so I understand (because the Halltech installation instructions are not clear to me), in the first photo of the "Beehive Install with Optional Cold Air Ports" instructions, are the two blue areas that Jim Hall is saying to "cut out" the same as the "Ram Air Induction Ports" shown in photograph four?
Thanks!
Platinum Supporting Vendor
Joined: Sep 2001
Posts: 3,665
Likes: 341
Correct, stock filter.. The propped shroud works perfect at WOT..
I removed the Halltech but kept the Beehive. It took a little cutting to get it to fit. If you seen my above post both my 11 Camaro SS and my 08 Vette ran slower at the dragstrip with the aftermarket CAI's. Both cars had stock tunes...
Note the rubber blocks holding the shroud open... They are coil spring spacers.. Still havent had a chance to drive the vette with the propped shroud on the stock intake with the beehive
Halltech Beehive modified to fit the stock intake....
I removed the Halltech but kept the Beehive. It took a little cutting to get it to fit. If you seen my above post both my 11 Camaro SS and my 08 Vette ran slower at the dragstrip with the aftermarket CAI's. Both cars had stock tunes...
Note the rubber blocks holding the shroud open... They are coil spring spacers.. Still havent had a chance to drive the vette with the propped shroud on the stock intake with the beehive
Halltech Beehive modified to fit the stock intake....
Justin
Safety Car
Joined: Oct 2003
Posts: 3,597
Likes: 101
From: TN PA
CI 5-6-7-8-9-10-11 Vet
You are absolutely correct about losing power with the aftermarket CAI's but not for the reasons you are indicating. The problem is the factory calibration on MAF transfer function. All fueling is based off the MAF sensor under steady state throttle under 4k RPM and the coefficient tables under transient throttle, above 4K it is all MAF. The reason you are "losing" power is because the LS3 goes from running a high 11 AFR to a low 10 AFR because of the increased amount of air. What happens is the higher flow of air is registering a higher frequency and the ECU is responding with more fuel, but too much fuel. If you were to recalibrate the ECU/PCM to fix this and bring the AFR back to the same as it was before you would see a fairly decent power increase.
Justin
Justin
I really had no reason for the slower times with the aftermarket cai's but what you posted makes sense.
For the record my best times totallly stock have been 12.127 @ 116.59 & 12.136 @ 117.81
My best times stock but with the shroud propped open and the stock filter removed have been 12.016 @ 116.26 and 12.03 @118.97. the mph would vary quite a bit with no filter... BTW a run on the same day with the filter in was a 12.11 @118.06
With the Halltech & Beehive my best were 12.268 @ 116.74 Even correcting for DA still leave it well short of the stock intake. (DA correct = 12.19 @117.44)
My results on my L99 11 Camaro with the aftermarke cai were about the same. Losing over .10 and 1 mph less..than the stock intake.
I have been running the Vette for 5 years so I have a pretty good base line on how it runs. For now I have no plans for a tune.
I'll report back when I run the car with the stock intake, beehive and propped shroud....
Race Director
Joined: Sep 2007
Posts: 16,557
Likes: 2,108
From: Peoria/Phoenix AZ
C6 of Year Finalist (performance mods) 2019
You are absolutely correct about losing power with the aftermarket CAI's but not for the reasons you are indicating. The problem is the factory calibration on MAF transfer function. All fueling is based off the MAF sensor under steady state throttle under 4k RPM and the coefficient tables under transient throttle, above 4K it is all MAF. The reason you are "losing" power is because the LS3 goes from running a high 11 AFR to a low 10 AFR because of the increased amount of air. What happens is the higher flow of air is registering a higher frequency and the ECU is responding with more fuel, but too much fuel. If you were to recalibrate the ECU/PCM to fix this and bring the AFR back to the same as it was before you would see a fairly decent power increase.
Justin
Justin
Platinum Supporting Vendor
Joined: Sep 2001
Posts: 3,665
Likes: 341
The AFR does not exactly get self corrected the way everyone thinks, it also depends on the different airbox's. I can't tell you what each airbox does because they are all a little different, but I can tell you what mine did. First let me explain the AFR issue. The car has a learn or LTFT in closed loop, lets say the LTFT was -3% when the car went into PE mode, it will carry that. That LTFT changes up to +/-25%. The car does not self learn for air box's and other mods, the LTFT was meant for different fuels and little errors. The airflow is really around the airbox and not the filter, so even removing it will not do a whole lot of changing if the filter was not a restriction to begin with. The Mamba box for example has twice the size of the opening in the box than a stock airbox, because of the shape of the box it speeds the velocity of the air inside the box so you end up with more air going into the engine and the HZ of the MAF is way higher which puts it into a different area of the MAF transfer function, which increase the amount of fuel drastically. This is why he lost power with the other CAI, if he were to correct the MAF transfer to correct the AFR he would see a decent power increase over the stock box.