Let's open the flood gates of discussion, shall we? CAI ...

Tech discussions on the L77 6.0L V8.
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Bowtie Junkman
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Let's open the flood gates of discussion, shall we? CAI ...

Post by Bowtie Junkman »

Opinions, please ... open element CAI (like a K&N Aircharger) ... not in general, but for our cars specifically ...

In theory ... the more air in, the better. The colder this air is, even better. I get that. Light modding like the CAI joined with a less restrictive exhaust and a tune, and there are definitely benefits that can be realized ... and I'm not talking about numbers on a dyno sheet or tenths of a second at the strip ... I'm talking about seat of the pants, tire squealing results during daily (spirited) driving.

So .. I understand by doing some reading of past threads that a G8 CAI does not "seal" properly due to the lack of an under-hood insulator on our cars. Thus allowing warmer under-hood air to be sucked in as well. Question ... is the overall benefit from the increased air intake volume and smoother transition to the throttle body still give more benefit (even with bringing some higher temp air in) than the stock box and intake tube set-up? I can't help think about every muscle car and Hot Rod that has ever had an open element air cleaner sucking in hot under-hood air for the last 50 years ... and yes, I realize that computer controlled cars are a tad different than Holley double-pumpers and Mallory dual-points ... And will "McGyver-ing" a taller piece of foam or insulation around the perimeter of the box help seal and in turn eliminate this issue? And without it (running the CAI without the seal mod), will the engine's performance potential be the same (or worse) than with the stock set-up? I'm intentionally leaving out the benefits of the better sound here ... and speaking strictly from a performance standpoint ...

And these Roto-Fab (and similar) set-ups with an enclosed box ... what is the benefit of these over the stock enclosed box (other than the new tube offering the smoother transition)? Do they draw air from a different (better) location? If not, how is their set-up different than the stock enclosed box (sans chambered air intake tubing)?

I don't have a lot of money to do cam-swaps and the like, so I need the easy, relatively inexpensive mods I can afford to do to bring me the most bang for my buck. But I certainly do not want to go backwards and spend money on something that will make it run the same or worse. I've already done my exhaust; a CAI and a tune are next, and then (eventually), the 3.45 diff swap.

I look forward to hearing opinions as well as tales of real-life experiences and lessons learned ...
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jpalmer
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Re: Let's open the flood gates of discussion, shall we? CAI

Post by jpalmer »

I have only had my Caprice for a few months so I am still coming up to speed on what options are out there. And, keeping in mind that my vehicle will be a daily driver, there probably won't be a "Maggie" in my future. My mods will be more conservative than some of the other guys and my list of upgrades will go something like this:

1. 2.5" cat-back exhaust w/ aftermarket resonators and mufflers
2. 3.27 or 3.45 LSD swap
3. Dyno-tune (not sure yet if it will be the full tilt 91 octane tune)
4. Cold air intake.

This last mod I have been kicking around and like you I have read the posts on the G8 cai not sealing to the hood. I am also not going to drop the bucks on a OTR unit ($500+), which leaves me with two choices.

First is the RotoFab piece that looks like it does it all and the price ain't that bad at about $325. Next is the AEM Brute Force Air Intake tube for $178 bucks delivered. I'm not sure if the RotoFab box and filter is worth the extra $150 when the stock box is sealed and the stock filter does a purty good job keeping junk outta the air flow. So right now I am leaning toward just adding the AEM Tube and calling it good. Maybe a DIY coating of some sort to keep heat soak at a minimum....

I'll keep watching the posts in this thread and see what others say.
Jeff

1996 Caprice LT1 B4U - Sold - So long my friend - it was a great 17 years!
2001 Silverado LS 3500 DuraMax Dually 4x4
2004 Suburban 2500 6.0L 4x4
2013 Caprice PPV 6.0L
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orgdnr
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Re: Let's open the flood gates of discussion, shall we? CAI

Post by orgdnr »

As much as I like the sound of my CAI, I think it is lacking the (C). Unless we have the cars driving next to each other it's hard to be sure. As far as airflow, my car at 6200 rpm is at 4 KPA on the map sensor. If you have someone watching the scan tool while you make a pass we can compare. If your #'s are higher, the stock intake is likely the restriction.
Dave
Chatsworth Ca

2012 9c1 ported LSA kooks 1 7/8 long tubes rotofab cai 575rwhp 570 tq. best repeatable 1/4 mile 11.32
69 Roadrunner 383 A/G 4 sp. bench seat (for sale) no rust
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Navy Lifer
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Re: Let's open the flood gates of discussion, shall we? CAI

Post by Navy Lifer »

Bowtie Junkman wrote:I understand by doing some reading of past threads that a G8 CAI does not "seal" properly due to the lack of an under-hood insulator on our cars.
G8 hood insulator fits--PN's here:
viewtopic.php?f=21&t=157&hilit=insulator#p1832" onclick="window.open(this.href);return false;

PN 92253505 G8 insulator is now listed as "discontinued"! May be time to have some custom insulators made with a logo (and no G8 "scoop" cutouts). Ideas for a logo? CP can provide the Caprice insulator, but it becomes a shipping issue unless a quantity purchase is made--and even then it's STILL going to cost more to ship them than it would be to have some made here, most likely.

Somewhere (I think) are posted pictures of the hood insulator, but it's not in a stand-alone thread (and the pictures may be corrupted at present). Some day I'll get them ALL fixed.

Also, take a look at Pursuit's thread with photos:
viewtopic.php?f=16&t=165" onclick="window.open(this.href);return false;
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Bowtie Junkman
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Re: Let's open the flood gates of discussion, shall we? CAI

Post by Bowtie Junkman »

JPalmer ...

We sound like we are thinking along the same lines ... similar conservative mods expecting similar results ...
This is the CAI I am looking at ... http://www.trickflow.com/parts/tfs-23082" onclick="window.open(this.href);return false;

It states it is made for TFS by K&N, so I am assuming it is very much like the K&N AirCharger... and I was happy with the one I put on my 2010 Camaro SS ...
Plastic tube, also important in my book as well .... and can be had for around $175 ... seems like a good deal ...
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Bowtie Junkman
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Re: Let's open the flood gates of discussion, shall we? CAI

Post by Bowtie Junkman »

OrgDnr

We talked about air intake temps before ... I think I'm going to pull the trigger on the TFS unit, and I'll have something to compare it to since I already have the numbers from the "drive to & from work" with the stock set-up now ...
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storm9c1
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Re: Let's open the flood gates of discussion, shall we? CAI

Post by storm9c1 »

I don't mean to be the guy to rain on anyone's parade, but what about modifying the stock air box to pull in air from a cooler location? The reason I ask is that back in my younger days (when I raced B-Bodies albeit without a transbrake or use of the launch controllers available today), I noticed ZERO improvement in 1/4 mile time. This was on a normally aspirated car with common bolt-on upgrades (ignition, intake, exhaust, LT1-Edit tune). And this proved that any "seat of pants" improvement was all in my head.

What I did notice with CAI systems were much dirtier MAF sensors and throttle plates. Guys at the track used to say "oh that's just the oil coming out of the K&N filter." So I wiped some of this "oil" off the inside of my CAI pipe and rubbed it between my fingers. It was gritty. Sorry, but I don't care where it came from, I don't want grit (or oil impregnated with grit) going into my engine. Even if it is oil, trust me, it's oil plus dirt.

After I learned this, I went back to running a stock airbox with nothing but smooth, straight intake pipes. Others also experimented with larger airboxes with OEM quality media. We saw no difference. A stock airbox with a good filter was fine, and the only improvement was seen with mods that could pull in colder air from the front of the car (ie: removing a headlight was a common quick mod). Nothing more was needed. If you do CFM area flow tests, the stock air boxes are usually way oversized already. So if it were me, I'd see if you could retain the stock air box and plumb it to pull air from a cooler location. This would also offer a great stealth look.

Just food for thought.

Some additional reading:
http://www.bobistheoilguy.com/airfilter/airtest3.htm" onclick="window.open(this.href);return false;
http://www.nicoclub.com/archives/kn-vs-oem-filter.html" onclick="window.open(this.href);return false;
Tom (AKA: Storm)
2011 Caprice 9C3: L77, 8K miles, first-owner, purchased July 2011.
1995 Caprice 9C1: LT1, 178K miles, summer car.
1995 Impala SS: LT1, 21K miles.
1995 Caprice Wagon: LT1, 62K miles.
1995 Caprice Wagon: LT1, 128K miles. Rust In Pieces
1994 Caprice 9C1: LT1, beater winter car.
1969 Chevy C30: 383ci stroker, 4L80E, rollback car hauler.
1972 Chrysler Newport: 400ci big block, survivor 27K miles, 2-door hardtop.
1969 Dodge Charger: 383ci big block.
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jpalmer
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Re: Let's open the flood gates of discussion, shall we? CAI

Post by jpalmer »

storm9c1 wrote:I don't mean to be the guy to rain on anyone's parade, but what about modifying the stock air box to pull in air from a cooler location? The reason I ask is that back in my younger days (when I raced B-Bodies albeit without a transbrake or use of the launch controllers available today), I noticed ZERO improvement in 1/4 mile time. This was on a normally aspirated car with common bolt-on upgrades (ignition, intake, exhaust, LT1-Edit tune). And this proved that any "seat of pants" improvement was all in my head.

What I did notice with CAI systems were much dirtier MAF sensors and throttle plates. Guys at the track used to say "oh that's just the oil coming out of the K&N filter." So I wiped some of this "oil" off the inside of my CAI pipe and rubbed it between my fingers. It was gritty. Sorry, but I don't care where it came from, I don't want grit (or oil impregnated with grit) going into my engine. Even if it is oil, trust me, it's oil plus dirt.

After I learned this, I went back to running a stock airbox with nothing but smooth, straight intake pipes. Others also experimented with larger airboxes with OEM quality media. We saw no difference. A stock airbox with a good filter was fine, and the only improvement was seen with mods that could pull in colder air from the front of the car (ie: removing a headlight was a common quick mod). Nothing more was needed. If you do CFM area flow tests, the stock air boxes are usually way oversized already. So if it were me, I'd see if you could retain the stock air box and plumb it to pull air from a cooler location. This would also offer a great stealth look.
Just food for thought.

Some additional reading:
http://www.bobistheoilguy.com/airfilter/airtest3.htm" onclick="window.open(this.href);return false;
http://www.nicoclub.com/archives/kn-vs-oem-filter.html" onclick="window.open(this.href);return false;
I think Tom's has a good point with a cold air source to the stock box. The diesel forum actually did a test of the modern cold air intakes vs stock (it was about 8 or 9 years ago) and the stock AC Delco filter held it's own with the high dollar CAI's. To the point that many of the guys, me included, stayed with the stock air intake even with mods.

Having said that, a diesel is more picky about contaminates so that was one of the criteria not just better air flow. And because of this I think getting rid of the restrictive intake tube with a smooth pipe would be great for anything less than all out modifications. THEN, if you plumb a cold air source into the box you'd be steppin' in high cotton!
Jeff

1996 Caprice LT1 B4U - Sold - So long my friend - it was a great 17 years!
2001 Silverado LS 3500 DuraMax Dually 4x4
2004 Suburban 2500 6.0L 4x4
2013 Caprice PPV 6.0L
xcidmigs
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Re: Let's open the flood gates of discussion, shall we? CAI

Post by xcidmigs »

I have a stock airbox K&N filter FS if anyone wants to experiment with these ideas before pulling the trigger on a CAI,
viewtopic.php?f=4&t=796" onclick="window.open(this.href);return false;

I did the same myself when i first picked up my car and was intending to use it like that for a while longer at least until i did some exhaust work but i found a very good deal on an OTR intake on ebay so i had to jump on it. I only used it a month or so and did not notice any major improvement but also did not accurately test anything. I can also tell you from personal experience the reason the diesel truck test may have shown that the oem paper type filter setup was close was 2 things, first it was most likely a brand new one used for testing combined with the low operating RPM range of diesel motors. I've repeatedly experienced first hand how bad a stock paper filter setup can be on a v8 high rpm use patrol car motor. Meaning that they use only stock paper filters in them and they get a ton of idle time which is not ever monitored for service intervals where i work at and so you have literally no idea how dirty they are until the box gets opened for replacement. I have had cars which seemed to drive fine as you putt around town handing out parking tickets, then the one time you need to have flat out response for whatever reason the car dogs out and by the time you get there seems like it has a major malfunction like fouled plugs etc. I've personally checked back to the garage after putting a vehicle down with that type of symptom and been told it just needed "a tune up was all" which in reality these days means they do a oil change and replace the filters. I've seen the old ones at times and they have literally been black with dirt and covered in all other types of crap like tree pollen etc. And the car afterward is like it has a new motor in it. The point I'm making is the K&N type panel filter has been shown repeatedly to do better at functioning 100% while even being somewhat dirty, and obviously its not such an ordeal to clean them either.
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Re: Let's open the flood gates of discussion, shall we? CAI

Post by 9C1fanatic »

Here is my two cents:

The factory air box actually does a good job of pulling "cooler" air in. It passes through a hole in the radiator support just above the inner bumper and is even sealed with a foam gasket to help keep out engine heat. I may be possible to get some improvement in cooler air by somehow drilling or otherwise modifying the fog lamp dummy plate which is below the air box inlet but would allow greater volume of ambient air to enter the cavity the air box is pulling from. It is already sealed off for the most part from the radiator also. I'm going to test this one day on the patrol car as the siren speaker is mounted behind the right fog dummy bezel and I thought drilling small holes between the honeycombs would help the sound some so of course I have to do the left side to match right?

That being said, I have the Roto-Fab CAI for the Chevy SS installed in a 2014 PPV. Stock tune. It is more expensive than the G8 model and is sealed in a box. The filter is large and looks to have more surface area than the OEM and has a larger induction tube that feeds the air box from behind the bumper cover just like the OEM air box but does not have a foam gasket like the OEM does. Now this is not completely fair because I did not formally test the car with just the air box but can tell you this:

I compared the car with another 2014 PPV with almost identical weight and mileage. Both full tanks of identical fuel from same station and same pump.

When both cars were stock, they ran neck and neck time after time like clockwork.


After installing the SS Rotofab CAI and the Solo axle back exhaust on one of them, it would walk the other car every time just like clockwork and im talking like 1-2 car lengths in the 1/8 mile.

Of course that could just be the axle backs but other threads suggest the OEM mufflers are not the restriction in our systems or it could be the combination of exhaust and CAI.

For what its worth.
Garner Ames



1975 Pontiac Grand Am L77 - 14.82 @ 92.89
1991 Chevrolet C1500 L31 Vortec/5 Speed
2002 Chevrolet Suburban 1500 LM7
2014 Chevrolet Caprice 9C1 L77 - 13.60 @ 105.87
2019 Chevrolet Express 3500 L96
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