Well guys... about cooling the inlet air. And this comes from my one and only bible - Turbocharging and Supercharging by Alan Allard. So, if you don't belive me, google his name and you will know who he is and what he has done in the world of charging engines.

"The effect of compressing air is to raise it's temperature. For every 150 F (65 C) increase there will be an effective loss in air density equivalent to 2.0 psi of boost."

I understand this so that if you have 14 psi of boost and your intake air temperature increases from 100 F to 250 F you loose 2 psi and you'll only have 12 psi in use. Right? One reason to cool intake air?

"The use of an intercooler (aftercooler) is important for two reasons. Intercooler cools the charge air and increases the density of the charge and therefore its mass flow into the engine. The greater mass flow of air allows a greater quantity of fuel/air mixture to be converted to power."

"Secondly, it reduces the thermal loading on an engine for given boost and power output. The reason for this is that, for every degree drop in temperature of the inlet charge, there is roughly similar drop on the exhaust side, which contributes to a reduction in thermal loading on valves and pistons and reduces the amount of heat which has to be dissipated by the engine."

"For example, engine with maximum boost of 12 psi (1.8 pressure ratio) with compressor efficiency of 65 per cent and an ambient air temperature of 20 C, the compressed air disgharge temperature will be approximately 130 C after passing through the turbocharger. If we fit a 70 per cent efficient intercooler, the temperature of the air entering the engine will have been reduced to 53 C." The 77 C reduction in charge temperature can be calculated to give four per cent increase to flywheel power."

"Some figures show a gain of as much as 1 hp increase for 1 celsius drop in charge air temperature."

So, what are you guys thinking.... 170F degree difference just with 12 psi of boost...

 Seppo from Järvenpää, Finland
www.hollowheads.net (just click the hole in the head to proceed)

Roots-style airmover is quite difficult to cool, because pressure is made in all the way from charger rotors to cylinder, so air is heating after intercooler too.That's why with roots-style charger its better to locate the cooler close to intake manifold as possible -> Bigger difference in temperature so better cooler effiency.
Water/methanolinjection must be good with Roots, cause you can cool air directly in manifold.(and you can hide the injectors quite easy)

Centrifugal-style chargers (and turbochargers) generates the pressure and heat in compressor so you can locate the intercooler where every you want.


Hyvinkää, FI

There are actually more benefits than two, lowering the inlet temperature with an intercooler.

Denser air/fuel into cylinders: more hp.
Less thermal load: healthy for components.

But also:
Higher efficiency (Carnot and the second law of thermodynamics): more hp
Less flow loss due to denser air/fuel: more hp.
Cooler inlet temperature means less prone to knocking, more ignition advance can be used: more hp
Cooler inlet temperature means less prone to knocking, higher compression ratio can be used: more hp
Cooler inlet temperature means less prone to knocking, higher boost can be used: more hp
Cooler inlet temperature means less prone to knocking: cheaper gas can be used: money saved

Well, an intercooler do restrict flow somewhat, but not much.

Conclusion: an intercooler has very positive properties, if you can stand the cost and space.
But, for a McCulloch supercharger with 7 psi boost it may not be worth the effort.

1987 Turbo Regal

1955 Mercury

Thats the general consensus of what I've been told. The Mccullouch units would not show much gain due to the low boost. Someday I hope to build a cool box around the hose from the supercharger to the carb hat and drop in some dry ice to see what it will do.

I've seen intercoolers for the roots systems that consist of a box that fits between the supercharger and the intake. Often cooled by water pumped through cooling fins. Chuck

Y's guys rule!
Looking for McCullouch VS57 brackets and parts. Also looking for 28 Chrysler series 72 parts. And early Hemi parts.

MoonShadow, 292 w/McCulloch, 28 Chrysler Roadster, 354 Hemi)
Manchester, New Hampshire

Intercoolers aren't an option in our book they get installed always. Intercoolers can be found extremely cheap on the internet often in any dimension you need with many inlet and outlet configurations.

http://www.cxracing.com Is a great place to find many intercoolers or just search the internet. There a lot of intercoolers for $100-$200 or cheaper. For 7-10lbs of boost it wouldn't take a large intercooler. I would highly suggest it because it is much safer for you engine in every aspect, not just for more power but for protection for your engine. Plus it adds a little trick look to your setup.

Hutz 292 is right. Intercoolers are cheap. Liquid to air intercoolers are compact, and preferable, but you need another cooler somewhere to cool the liquid. With a liquid intercooler you can use ice, ice/salt solution (0F or -18C), or dry ice tog get the air really cold. You can also hook up you air condition to the intercooler. With a glycol/water in your system you can manage -40F or -40C . That would be nice for a hot Y-block.You can build one your self for free from scrap parts. I'm putting together one with fifties parts, just for fun and look, but still has much work left with the setup. Remember, the Merlin V12 during WWII used both a centrifugal supercharger like the McCulloch AND a liquid intercooler, and nitrous injection .

1955 Mercury

I don't quite recall the Merlin V12 from World War II

You can find Rolls Royce Merlin V 12's in those unlimited hydroplanes.

Mark

1956 Mercury M100
1955 Ford Fairlane Club Sedan
Delta, British Columbia

Exactly, the "unlimited" Hydros of the fifties, "Slo motion" , miss Budweiser etc. used them I think without the nitrous. Awesome sound, sorta like a citizen of Hamburg or Dresden must have heard in 1944 and '45. They're all gone now, replaced by Turbines. When I was a kid my Dad would take me to the races on the Detroit River, it was quite a sight for kid believe me!

Frank/Rebop

Bristol, In ( by Elkhart) 

The hydroplanes also used the bigger Rolls-Royce Griffon 2240 cu in, a "Y-Block", 2000+ hp . Griffon is similar to the Merlin and used in airplanes such as the Spitfire, and was later also put in a modified P-51 Mustang for competition.

For inspiration , I took a picture of the liquid/air intercooler for the Griffon, which is cut for visibility. The blue color shows air/fuel mixture, and the green color is the water/glycol part.

Before making a homemade intercooler, think of the forces. If my calculations are right, a 10x10 inches surface or joint will at 28 psi boost create a force of over one ton , that can explode right into your face .

1955 Mercury