Originally Posted by ADM PERFORMANCE
WARNING: It's an accepted known fact that any engine makes more power on cold
air than hot air. Use of this product negatively alters the "cool air" design of the
stock OEM inlet system and instead inhales underhood "hot air." This device reduces
air density (HP and torque), increases the engines tendency to
knock/detonate/ping which can result in lost power and potential engine damage,
especially with superchargers or turbos. Not recommended for Kenne Bell
supercharger kits. Voids warranty.
Let's all sit back and take a deep breath of fresh air (cool air). Now, crawl under the hood of your vehicle, lay across the engine, close the hood over
you and take a deep breath of all that hot air from the radiator fan (160°-200°), engine (160°-220°) and headers (up to 1000°). Who the hell would do
that, you say? Well, when companies sell you a "cool air" kit with an exposed underhood filter that sucks in the same hot 200° air from that heat
soaked engine compartment, how do you think your engine likes all that hot power robbing air vs. theOEMfactory set up that inhales isolated ambient
70° fenderwell air? Then there's all that hot air the fan blows around. Remember the fan. It sucks hot air in off the hot radiator. Why do you think that for
the last 25 years every vehicle manufacturer on the planet avoids hot underhood air and fan wash like the plague and instead draws cool dense air
from the fenderwell, cowl or hood scoops?
We're not exactly inexperienced in this technology ourselves. Kenne Bell engineered and has sold thousands of functional RamAir/Cool Air kits for
the Mustang, Cobras, Buick GN's, Syclones, Dodges etc. They pull in cool air from the fenderwell, under the bumper or out of a hood scoop. In
contrast is the cheapie "cool air" kit gang who proceeds to eliminate all those expensive plastic molded hoses and fittings and "sticks" a filter onto the
end of a chrome or plastic pipe and calls it a "cool air," "cold air," "chiller," "hi-flo," or ??? kit.
It is, of course, your decision if you choose for your engine to suck in this hot underhood air with one of these over the counter or "custom" kits.
However, these things are not good for our superchargers and we not only don't recommend them, we are warning against the use of them. Look at
the facts. 10° of hotter air is equivalent to 1 psi of boost. That means the difference between the fenderwell ambient 70° system and the hot underhood
air temp can be an amazing 130° (200°-70°=130°) hotter. That 130° equates to about 13 psi of additional boost (13x10°=130°). So, you thought your
engine was only seeing the increased temperature of 100° from 10 psi boost (10x10°=100°).Wrong. It's 100°+130° or 230° plus the ambient. That's
the air temp of 23 psi boost! Surprised?Are you getting the picture yet?
The Kenne Bell supercharger - or any supercharger - doesn't like another 130° of air temp that is the fault of someone else's product. Neither does
your engine. As the old saying goes, ." Don't make those "cool air" kit problems Kenne Bell problems.We've
had our fill of these things. Lose those lame excuses for an inlet system. Our warranty is void if using one - and we can tell if you did.We apologize for
our frank unwavering approach, but the many warnings throughout our literature has failed to curb their use with our supercharger kits - and caused
Kenne Bell some expensive warranties.Try sending your supercharger repair bill to one of these "hot air" kit manufacturers and tell them their "hot air"
system killed your supercharger. Are these underhood filter kits any less liable than: 1. Tires that split or separate, 2. Wires that catch fire, 3. Sand
polluted oil, 4. Spark plug tips that fall off. I think not. There's no warning in the products. They are most certainly detrimental to engine performance. If
ANYONEdisagrees, get a magazine writer and let's do the tests.
"Don't make your problem my problem
FILTER FAN SHROUDS
Did you know that a dyno run with the hood open vs. closed with an underhood exposed filter can be 30HP.We ran this test for 2 different magazines.
Then there's the fan wash. Those who believe that "shrouds" actually solve the temperature problem must also believe in the tooth fairy. Shrouds may
help the mass air meter signal from being distorted and skewing the fuel delivery to your engine, but in no way do these metal shields magically
dissipate that hot underhood air. The hot air then enters the filter from the other side of the shroud.
Finally, there's the removed headlight with the filter behind it (in the hot engine compartment, of course). This is just another "hot air" system. It
remains underhood and blasted by hot fan air.At best, it's a hot air - cool air mixer at high vehicle speed as it does not - and cannot - pull in cool air.
Every engineer in the universe clearly understands the disadvantages of hot air and therefore designs their inlet systems to ingest cool dense air from
the fenderwell, cowl or hood. This is not rocket science. JUST SUPPLYYOUR SUPERCHARGER WITH COOLAIR 100% OF THE TIME. All Kenne
Bell supercharger kits connect to the stock cool air inlet system.We may also upgrade and/or offer an optional system for higher HPapplications.We
even offer some "all out" 5" racing systems. And we are not condemning cool air kit products that are designed to use cool air. Many of them are
functional and may be used with our kits.
The Kenne Bell Twin Screw Supercharger is essentially an air compressor and an air tank combined. That is why it is so potent and capable of
generating full instant boost at the flick of the throttle at any engine rpm. It's akin to an air hose (throttle) connected to the air tank (supercharger). The
handle (trigger) regulates the air flow (boost) into the engine. Engine rpm has little to do with the boost delivery. Boost is regulated with the gas pedal.
Abasic law of physics tell us that all air is heated when compressed, regardless of the supercharger or turbocharger type. To lower the superchargers
air temperature at idle and cruise, we rely on a bypass valve which "dumps" the hot compressed air in back of the throttle body where it is
"decompressed" and the temp is thereby lowered with the help of the cooler incoming ambient air flow through the throttle body. Unfortunately, at idle
and cruise, the throttle body is closed or barely open thereby allowing relatively little new cool air flow into the supercharger. So, the last thing on this
planet that our supercharger needs is more hot 200° air from those ridiculous, useless, power robbing underhood "hot air" systems. LOSETHEMand
use a 4" or 5" hose (depending onHPlevel) to pull cool air out of the fenderwell just like all the OEM's, racers and the knowledgeable do.
HEADLIGHT KITS
THE TWIN SCREW SUPERCHARGER
only
WARNING
WARRANTY IF THIS SUPERCHARGER IS USED
WITH A "HOT AIR" UNDERHOOD INLET SYSTEM
VOID
"HOT AIR" UNDERHOOD INLET KITS
sc-inst_misc\hotairwarning.cdr rev 03/30/05
Overheating your engine or supercharger will damage both. One has pistons - the other uses rotors. Both are aluminum and expand with
heat. An '03 Cobra test was recently run on our dyno comparing a fenderwell filter to an open filter with the hood OPEN and a huge fan
blowing on it to simulate 90 mph. The temperature difference was a whopping 45° hotter. Oops! An engines coolant temperature is
approximately 160°-200°. That is the temperature deemed "safe" by engineers for over 100 years. Obviously, higher temperatures should
be avoided because excess coolant temperature expands the pistons, thereby reducing the piston to bore clearance to a critical "0". The
piston then scores and/or seizes in the cylinders. Excessive heat will also cause the rotors to expand and score the supercharger case
and/or seize the rotors. Both are typically ruined because of the scoring and metal transfer. Never a pretty sight.
Needless to say, you wouldn't knowingly install some lame product or concept that increases your engine water temperature 130° to a
ridiculously hot 290° to 330° and cause your pistons to seize up and ruin your engine, to say nothing of the power loss from this hot air (1%
power loss for every 10°). Also, there's the increased potential for detonation and more engine damage. Oops!
Would you buy some kit that removes your engine fan? How about a "concept" that advises you to drain 50% of the engine coolant - or
spark plugs 6 heat ranges too hot? Of course you wouldn't. One would have to be totally and technically incompetent, ignorant or brain
dead to offer products or suggestions that destroy your engine - right? Wrong, they do - and these people create big problems for the
vehicle manufacturer and Kenne Bell. You would have no legitimate or ethical case for getting your engine warrantied by the factory. And
you can forget about those companies who sold or recommended those products paying the tab.
Your supercharged engine doesn't like it. So why destroy your Kenne Bell supercharger - and possibly your engine - with 130° hotter air
from one of these cheap HOTAIR UNDERHOOD OPEN FILTERS? "Hot Air" kits are akin to "interheaters" (the opposite of intercoolers).
Don't do it! Use a SEALED filter set up that pulls cool air from the fenderwell, cowl or hood. No underhood air allowed. No half ass baffles
either.
One more time.Avoid all who sell and promote these things for use with Kenne Bell supercharger kits. They obviously don't know, don't care
- or both. These products can destroy your supercharger and/or engine with "the hots." .
We recently ran a filter temperature comparison on Earl's 700HP 9 second Cobra. The hood was open with a high speed fan blowing cool
air into the front of the car. The dyno room temperature remained the same for both the fenderwell located cool air filter and the hot
underhood filter installed on the end of the mass air meter ("hot air" filter) located behind the headlight. However, even with the hood OPEN
and the fan blowing air over the top of the filter, temperature was 45° hotter with the filter sucking hoot underhood air off the end of the mass
air meter. That's the equivalent of approximately 4 psi of boost and a 4%HPloss. Read on.
Did you really believe that a cylindrical filter would magically not suck that bottom hot air from the headers, radiator, etc. and NOTmix it with
the "top cool air" at the filter top? Of course, the filter will average the "hot" and "cool" air, but it won't be as cool as the fenderwell air. That is
why everyOEMmanufacturer on the planet avoids hot exposed underhood filter designs. Now, if 10° is equivalent to a 1%drop inHP(that's
how you calibrate dynos), doesn't the 45° higher air tempREDUCEHPby 4.5%? Oops!
Where does your dyno tuner measure air temp? We've found that the best place to accurately increase air temp is at the entrance of the
supercharger. "One of the real dangers in running a test is you are bound to get data." So if you test on a dyno, use the SAE (Society of
Automotive Engineers) calibration for the particular weather conditions to insure accuracy, but you must test the RIGHTWAY and use the
correct temperature that your engine sees and not the temperature at some random location in the dyno room. The engine is not using the
air next to the dyno computer, is it?
It is not our desire to be critical of anyone or their test procedures. We are only pointing out a common variable in dyno testing that we at
Kenne Bell have found to effect test accuracy.
Note: Our supercharger rotors behave identically to pistons when overheated. The only difference is hotter air instead of hotter
water causes the failure. 130° is equivalent to the heat generated by another 13 psi of boost. Oops! Keep in mind that we can
easily determine if hot underhood air was the cause of the supercharger failure, just as an OEM can determine if his engine was
overheated.
And they void your warranty
HOW HOT AIR CAN DAMAGE YOUR SUPERCHARGER & ENGINE
DOES YOUR SUPERCHARGER & ENGINE HAVE "THE HOTS?"
OPEN HOOD FILTER TEST ('03 Cobra)
AIR MIXING & AIR TEMP SENSOR LOCATION
RADIATOR
FAN
270
270
200
200
200
200
70
70
135
135
200
70
70
70
70
SUPER
CHARGER
BYPASS
VALVE
HOT RADIATOR AIR
AND FAN WASH
COOL FENDERWELL AIR
ISOLATION PLATE
70 HOT AIR MIXES WITH 135 AIR
NOTE: SUPERCHARGER AIR ASSUMED TO BE 200 DEG FROM
20 PSI BOOST (~10 DEG PER POUND OF BOOST) FOR
COMPARISON.
COOL AIR KIT
RADIATOR
FAN
400
400
200
200
200
200
200 200
200
200
70
70
70
SUPER
CHARGER
BYPASS
VALVE
HOT RADIATOR AIR
AND FAN WASH
HOT UNDERHOOD AIR
FENDERWELL
FILTER EXPOSED
TO HOT AIR AND
TURBULENT FAN
WASH
200 HOT AIR MIXES WITH 200 AIR
A 10 DEG RISE IN AIR CHARGE TEMP. RESULTS IN A 1% LOSS IN HP.
(example: 50 DEG = 5% = .05 x 300HP = 15HP)THAT'S HOW THE WORLD CALIBRATES DYNOS FOR VARYING AMBIENT
TEMPERATURES. SAE IS THE MOST COMMONLY USED CONVERSION.
HOT AIR KIT
|