Fabricating cold air intake inlet
#11
10-05-2007, 08:24 AM
RE: Fabricating cold air intake inlet
Sharper Image sells a $50 device
that could be mounted inside an air-tight box
and used to measure both the air temperature
and air pressure of air box modifications:
http://www.sharperimage.com/us/en/ca...uct/sku__CE352
Modifying an airbox 'by eyeball' is a fool's game.
Want a 2nd opinion on that?
Check out how the legendary Chrysler 426 Hemi designer
and later General Electric diesel engine designer
Tom Hoover modified the air inlet system on his Coronet with a 426 Hemi:
-------
Okay, I found it. I can e-mail you scans from the article--I don't want to
store copyrighted pictures on my photo site.
From "Terror of I-696," by Nick Brunt,
Mopar Action, October 1993:
Tom Hoover had bought the Coronet brand new, specing it out with the
new-for-'66 Street Hemi and TorqueFlite trans. Back in those days if you
custom ordered a car, for a few bucks more, the factory would stick a plaque
engraved with your name on the glove box. Hoover thought this was a neat idea
and ordered the nameplate. It remains on the car to this day.
(...)
Chrysler's chief nemesis at the time was Pontiac. The poncho guys had cooke
dup a real hot cheater Firebird that ran a stroker crank among other things.
Hoover's goal with his Coronet was basic rodding--make the car lighter and
increase its power. So with 10,000 miles on the odometer, out came the stock
engine. It was later used in the first blown Ramchargers funny car. Nothing
went to waste. The fact that Hoover, as a member of the Ramchargers, had
access to all of the trick parts in Chrysler's racing program didn't hurt
either.
The engine buildup started with a new A102 Street Hemi block bored .040" over,
and running 11-to-1 compression with standard variety TRW pistons wearing
tight gap moly rings. Off-the-shelf aluminum A990 heads were used after first
receiving some custom port work and a trick valve job. The heads and other
aluminum parts, such as the oil pump and water pump housings were right out of
the '65 racing program parts bins. Hoover got together with his friend Racer
Brown and developed a special grind hydraulic cam for the beast. It would
later be known as the SSH25. Standard Street Hemi valve springs were installed
at a 1.88" height and were secured by Trick Titanium retainers.
...Mickey Thompson experimental aluminum rocker stands and roller-tipped
aluminum rockers...custom oil pan with windage tray. In another collaboration,
Hoover got together with Hooker and they developed the first set of Hooker
headers from a Hemi B-body...
Better breathing on the intake end was helped along by a bored-out Vanke-style
manifold and a pair of 750 cfm Carter AVS carbs with 1-11/16" throttle bores
and progressive linkage replacing the stock 625 cfm carbs. A second fuel pump
was added just ahead of the tank.
Probably the trickest setup on the car was Hoover's homemade hidden ram air
system....[wind tunnel] tests indicated that the inner headlight was the area
of highest pressure. But removing the headlight would have destroyed the car's
stock appearance. After all, he could have just used a hood scoop.
The parking light proved to be the area of second highest pressure, pulling 8
in. of water at 60 mph. Removing the parking lights was a more subtle, less
noticeable touch. Hoover made his own ducting and ran hoses to the modified
air cleaner.
...Hoover removed the rear window regulators, the rear seat and installed
corporate A-100 van seats up front. Seat brackets were aluminum..from the
'64-'65 AFX program.
...basically stock TorqueFlite running a standard A102 (Hemi) torque converter
and a mildly tweaked valve body. A modified pattern B&M Slick Shift...A 3.91
Sure-Grip rear went in at the time of the engine swap.
...skinny 7-inch Atlas Bucron tires...Hoover installed 6-cylinder torsion bars
up front for a better launch, relocated the battery to the trunk and ran Super
Stock rear springs and a pinion snubber. He further reduced front end weight
by converting the power steering to a manual setup. A fiberglass front bumper
bought for the car was never installed.
Ready to race, with 1/4 tank of gas, the Dodge weighed in at 3400 lb. Best
time in "daily driver" trim--through the pipes and street tires was 12 seconds
flat at 117 mph.
...
The Dodge also wears the prototype 1968 "Hemi" emblems on the fenders that
Hoover installed. Since the model is a Coronet 440, Hoover wanted to avoid the
confusion of folks thinking the car had a 440 engine. The Hemi emblems made
sure the street rats knew what it was that beat them.
(Copyright 1993 by Harris Publications, Inc.)
that could be mounted inside an air-tight box
and used to measure both the air temperature
and air pressure of air box modifications:
http://www.sharperimage.com/us/en/ca...uct/sku__CE352
Modifying an airbox 'by eyeball' is a fool's game.
Want a 2nd opinion on that?
Check out how the legendary Chrysler 426 Hemi designer
and later General Electric diesel engine designer
Tom Hoover modified the air inlet system on his Coronet with a 426 Hemi:
-------
Okay, I found it. I can e-mail you scans from the article--I don't want to
store copyrighted pictures on my photo site.
From "Terror of I-696," by Nick Brunt,
Mopar Action, October 1993:
Tom Hoover had bought the Coronet brand new, specing it out with the
new-for-'66 Street Hemi and TorqueFlite trans. Back in those days if you
custom ordered a car, for a few bucks more, the factory would stick a plaque
engraved with your name on the glove box. Hoover thought this was a neat idea
and ordered the nameplate. It remains on the car to this day.
(...)
Chrysler's chief nemesis at the time was Pontiac. The poncho guys had cooke
dup a real hot cheater Firebird that ran a stroker crank among other things.
Hoover's goal with his Coronet was basic rodding--make the car lighter and
increase its power. So with 10,000 miles on the odometer, out came the stock
engine. It was later used in the first blown Ramchargers funny car. Nothing
went to waste. The fact that Hoover, as a member of the Ramchargers, had
access to all of the trick parts in Chrysler's racing program didn't hurt
either.
The engine buildup started with a new A102 Street Hemi block bored .040" over,
and running 11-to-1 compression with standard variety TRW pistons wearing
tight gap moly rings. Off-the-shelf aluminum A990 heads were used after first
receiving some custom port work and a trick valve job. The heads and other
aluminum parts, such as the oil pump and water pump housings were right out of
the '65 racing program parts bins. Hoover got together with his friend Racer
Brown and developed a special grind hydraulic cam for the beast. It would
later be known as the SSH25. Standard Street Hemi valve springs were installed
at a 1.88" height and were secured by Trick Titanium retainers.
...Mickey Thompson experimental aluminum rocker stands and roller-tipped
aluminum rockers...custom oil pan with windage tray. In another collaboration,
Hoover got together with Hooker and they developed the first set of Hooker
headers from a Hemi B-body...
Better breathing on the intake end was helped along by a bored-out Vanke-style
manifold and a pair of 750 cfm Carter AVS carbs with 1-11/16" throttle bores
and progressive linkage replacing the stock 625 cfm carbs. A second fuel pump
was added just ahead of the tank.
Probably the trickest setup on the car was Hoover's homemade hidden ram air
system....[wind tunnel] tests indicated that the inner headlight was the area
of highest pressure. But removing the headlight would have destroyed the car's
stock appearance. After all, he could have just used a hood scoop.
The parking light proved to be the area of second highest pressure, pulling 8
in. of water at 60 mph. Removing the parking lights was a more subtle, less
noticeable touch. Hoover made his own ducting and ran hoses to the modified
air cleaner.
...Hoover removed the rear window regulators, the rear seat and installed
corporate A-100 van seats up front. Seat brackets were aluminum..from the
'64-'65 AFX program.
...basically stock TorqueFlite running a standard A102 (Hemi) torque converter
and a mildly tweaked valve body. A modified pattern B&M Slick Shift...A 3.91
Sure-Grip rear went in at the time of the engine swap.
...skinny 7-inch Atlas Bucron tires...Hoover installed 6-cylinder torsion bars
up front for a better launch, relocated the battery to the trunk and ran Super
Stock rear springs and a pinion snubber. He further reduced front end weight
by converting the power steering to a manual setup. A fiberglass front bumper
bought for the car was never installed.
Ready to race, with 1/4 tank of gas, the Dodge weighed in at 3400 lb. Best
time in "daily driver" trim--through the pipes and street tires was 12 seconds
flat at 117 mph.
...
The Dodge also wears the prototype 1968 "Hemi" emblems on the fenders that
Hoover installed. Since the model is a Coronet 440, Hoover wanted to avoid the
confusion of folks thinking the car had a 440 engine. The Hemi emblems made
sure the street rats knew what it was that beat them.
(Copyright 1993 by Harris Publications, Inc.)
#12
10-05-2007, 10:14 AM
RE: Fabricating cold air intake inlet
Interesting idea to use a weather station with temperature and barometer to measure the airbox. I wonder if the barometer would react fast enough in such small increments to show the air pressure readings at any given time.
I would suspect that with this mod, even a tissue covering the 3-4" hole would not stay held in place at full throttle or maybe not even get sucked into the air box. (Maybe I'll go out and try it.)
As for the article above, it is kind of a tough read to get through without pictures. Correct me if I am wrong, but, it looks like they were more interested in ram air, which to me would be an active system whereby air is packed into the system by the vehicle moving through the air.
The airbox mod this thread is talking about seems to be a passive system with the intent of removing some restriction of available air to the air box and adding more "cooler than under the hood air" to be sucked into the system.
I would suspect that with this mod, even a tissue covering the 3-4" hole would not stay held in place at full throttle or maybe not even get sucked into the air box. (Maybe I'll go out and try it.)
As for the article above, it is kind of a tough read to get through without pictures. Correct me if I am wrong, but, it looks like they were more interested in ram air, which to me would be an active system whereby air is packed into the system by the vehicle moving through the air.
The airbox mod this thread is talking about seems to be a passive system with the intent of removing some restriction of available air to the air box and adding more "cooler than under the hood air" to be sucked into the system.
#13
10-05-2007, 08:39 PM
RE: Fabricating cold air intake inlet
Correct me if I am wrong, but a "ram air" system is not really of any use in our trucks. The turbo already "rams" more air into the engine than you could ever accomplish with a "ram air" system.
The purpose of the aftermarket and/or modified intakes on our trucks is to allow more air into the system, not so much to "ram" it into the system. In the story the "ram air" system was rated at 8 in/H2O, that is only .29psi. I believe our turbos put much more air into the intake than that.
The purpose of the aftermarket and/or modified intakes on our trucks is to allow more air into the system, not so much to "ram" it into the system. In the story the "ram air" system was rated at 8 in/H2O, that is only .29psi. I believe our turbos put much more air into the intake than that.
#16
10-05-2007, 11:23 PM
RE: Fabricating cold air intake inlet
One would be surprized how snow might pack up... have a look
[IMG]local://upfiles/36650/CE623E2DDD4C4F009B21BC66260A01E7.jpg[/IMG]
[IMG]local://upfiles/36650/40368D2235C94BC38251CFE977F60BB2.jpg[/IMG]
[IMG]local://upfiles/36650/1247E2D4F7674B9CAC6001D919DB9F6E.jpg[/IMG]
[IMG]local://upfiles/36650/CE623E2DDD4C4F009B21BC66260A01E7.jpg[/IMG]
[IMG]local://upfiles/36650/40368D2235C94BC38251CFE977F60BB2.jpg[/IMG]
[IMG]local://upfiles/36650/1247E2D4F7674B9CAC6001D919DB9F6E.jpg[/IMG]
#17
10-05-2007, 11:32 PM
#19
10-08-2007, 10:03 AM
#20
10-08-2007, 01:18 PM
RE: Fabricating cold air intake inlet
If you study the efficiency tables from the manufacturer
for any given turbocharger
you will see that going from inlet air with 404 inches of water pressure
(normal atmosphere also equal to 14.7 psi or 30 inches Hg barometric pressure)
at the turbo inlet
to a higher 404+8=412 air pressure at inlet
pays off handsomely in more boost downstream of the turbo.
In a similar way
a lower air temperature at the inlet
is multiplied in its effect on the temperature of the boosted air coming out
This is even more important on a turbo than on a belt driven supercharger because turbochargers are less efficient compressors.
The idea that
"The Turbo will overcome all limitations"
or the other similar idea that
'The Intercooler will atone for all sins'
does not hold up.
There is also the tech term 'transient response'
which in Cummins Ram forums is usually called
'turbo spool up lag'
that changes in a superior way as the inlet air pressure rises
on 'cold' side of the turbine wheel.
{lower the exhaust gas pressure on the hot side of the turbine wheel and transient response improves too}
It is kinda like the old proverb:
The Devil is in the Details
for any given turbocharger
you will see that going from inlet air with 404 inches of water pressure
(normal atmosphere also equal to 14.7 psi or 30 inches Hg barometric pressure)
at the turbo inlet
to a higher 404+8=412 air pressure at inlet
pays off handsomely in more boost downstream of the turbo.
In a similar way
a lower air temperature at the inlet
is multiplied in its effect on the temperature of the boosted air coming out
This is even more important on a turbo than on a belt driven supercharger because turbochargers are less efficient compressors.
The idea that
"The Turbo will overcome all limitations"
or the other similar idea that
'The Intercooler will atone for all sins'
does not hold up.
There is also the tech term 'transient response'
which in Cummins Ram forums is usually called
'turbo spool up lag'
that changes in a superior way as the inlet air pressure rises
on 'cold' side of the turbine wheel.
{lower the exhaust gas pressure on the hot side of the turbine wheel and transient response improves too}
It is kinda like the old proverb:
The Devil is in the Details