MILD THUNDER

iTrader: (3)

Is this BS or real numbers? I can see the 190* air temp being realistic without a chiller with a roots.

http://www.rbssuperchargers.com/Prod...D0068&pID=6045

MDGperformance

I did some tests years ago with a 454 b-m 250 blower 5lb boost around 550 hp tested without chiller then installed chiller basically no power gain,we then changed the pulley to 7lb made another 25-30hp,all test we were using 93 pump gas on a superflow dyno,i think you were to install chiller and not add boost you would see gains in performance on a hot summer day,your hp loss would be less with the chiller,we use to run the 454 7.5 compression 10-12 lb boost on pump fuel using bm 250 and superchiller 700hp ,never had a problem

MILD THUNDER

iTrader: (3)

According to my book on supercharging, they get into some high tech scientific formulas. They give an example. If you had a setup that took in a ambient air temp of 68*, and compressed it to 7.4psi ,a compressor with 100% efficiency would net a discharge temperature of 131*. Well, we know that no such thing as a 100% efficient compressor. They say most roots blowers are 50% adiabatic efficient. With that said, the inlet air temp being 68*, would heat the intake air to 194* at 7.4psi. This formula, is almost dead nuts on what RBS superchargers claims in that link. Now, since we are talking about blower adiabatic efficiency, now you can understand why a Whipple, being a more effiecient compressor, will net cooler air charge at same boost level. Cooler air=more power. The more efficient the compressor, the cooler the charge. Im sure eddie young can tell you first hand, pound for pound of boost, a whipple will outperform a roots almost everytime.

But, that brings us back to the question. If you install a chiller, and do not change pulley's, from what ive seen, most guys do not gain power, as they lose 1-2psi. I personally think its from the restriction of airflow thru the core. If it were simply because the charge is cooler, power would go up just from bolting it on. That doesn't seem to be the case. However, if the baseline was 7psi non intercooled manifold boost, and you compare it to 7psi manifold boost intercooled, you should see a increase in power. IMO, losing 1-2psi in the manifold, will cost more power than whatever the charge temp is. Getting the manifold pressure back to where it was, is the idea. Now, you have the same manifold pressure, a cooler charge (more power than baseline), and less chance of detonation.

Im sure Eddie can enlighten us better.

mcprodesign

You can add like 3 pounds of boost when you go to a superchiller. The smaller the air the better and the colder the air the smaller.. It;s a no brainer. You can probably go at least a half inch down on the top pully if you switch. Ihave been told you can get 50 - 75 hp amotor easily. I thonk it's worh it.

Also are you running a mercury fuel injection. or something comperable? If you are not running fuel injection you will need to plumb the whole thing seperate or your boat will idle like the choke is on ( because the coole rair) .. Mine has mif and idles perfect right of the water pump..

If you go without fuelinjection and runa whole seperate system. .it will be had to wash all the salt water out.. If you run off the stock waterpump it just stays wet in the whole cooling system ( including the chille) .. Then you can keepp it wet until you flush w no saltwater damage as well

Smitty

iTrader: (1)

Do an extensive search on here. I know in the past that someone has tested this before. And I also think that Biggus added chillers when he switched his blowers over to BDS. He had stock 575 motors. Post up for him in the Cig section. Also I believe Dustin has some kind of results testing his MOAC chillers against a Super chiller. Also if you do add any kind of chillers, DO NOT pull your water off of your main water supply. Use a set of transom pick ups or water thru the drive. Doing so will keep the fuel from going back to droplets which will load up your motors at no wake speeds.

Randy Nielsen

iTrader: (4)

My 3.3 top mount whipple says in bold letters to not use the main water supply for the intercooler because the intercooler is not needed @ low rpm. They must have learned that from experience because my side mount intercooler WAS plumbed through the cooling system. The boat ran ok for short idle times but would start to load up if I idled for any length of time over 5-10 minutes. As a side note the engine had champion plugs in it & my experience with champions is that they are junk in anything but a Chrysler product. Jmo Randy

mcprodesign

you can run off the main water supply w Mercury fuel injection. Mine runs perfect and like I said . When you run salt water . the waterpump will keep water in your motor will keep your chiller wet over night, like Catalina or when you pull it out and they wont let you flush at the launch ramp ( welcome to san diego)My motors started out as 04 575's,

ICDEDPPL

iTrader: (1)

I figured I`d use my blow off valves for water.. they don`t open till on plane.
No salt water around here MACPro

MILD THUNDER

iTrader: (3)

Yes, our buddy has them plumbed that way. At idle , no water psi, so cooler isn't getting water. As soon as water psi hits like 6psi, pressure relief valve opens, sending water thru the core . He had high water psi to begin with, so now instead of blowing that water off and dumping overboard, he feeds his chiller with it .

mcprodesign

mine runs 8 - 10 psi and about 2 at idle. The best part is with my set up it dumps water out the side of the boat at idle almost like the bilge is on. this keep water out of the headers. and makes "HIM" idle REALY loud
I just stand behind it and let my ears ring at the docks/ That's probably my favotire part of boating. That and the bj's under the deck. your set up sounds like a great Idea