Hot Boat

I was thinking of adding a inter cooler to my 454 with a 177 blower on it. The motor built just about 600 HP but had 565Hp at 5300 rpm. I am only running 4 Lb of boost with a set of long tube headers and the motor is breathing cool air through a hole in the hatch. I am running a oil thermostat to keep the oil hot but my water temp is very cold. I didn't even see it above 110 degrees yet.

If I was to add a inter cooler what kind of gains could I see if any. I heard deferent opinions and also heard that there is minimal gains on the 177 blower. That sounds strange to me because the 177 runs very hot and would seem a prim candidate for a inter cooler. also if it was inter cooled could I safely be able to run a bit more boost like 6 psi or so. What kind of HP gains could be expected with the inter cooler and 2 psi more boost???

Smitty

I would have to guess at maybe 50 hp if you added a cooler and went to 6 psi boost. I would not go over 6 psi with that blower. It generates to much heat. Putting a chiller on is almost a mandatory thing on a marine application for longevity because of the load on the motor. Give Dustin a call at whipple and see if they sell a chiller to work with that blower. They have awesome coolers. I have a Whipplecharger on my stock 454 w/chiller and it runs really good and runs cool.

Dave

Hot Boat

Thanks Big Wavz I will have to get a hold of him

I Also heard that you have to increase the boost to compensate for the loss in pressure created by the inter cooler. and that I might have a problem with fuel puddling up on the bottom of the intake at low rpm due to the restriction in the cooler. is this all true ????

it is sounding better to just leave everything the way it is rather than run the cooler and turn the blower faster.

mltdwn12

Those blowers are orignally designed to make about 550 horsepower. You're there now You will see a slight drop in boost just because you've introduced a restriction in the intake track. Don't know if it's really that much. You can avoid the puddling deal by running your water supply to the intercooler off of a separate offshore style pick up vs tapping into the seawater pump hose. At idle and below 30 mph or so, it's not really cooling anything and therefore super cooling the charge. Once you get the boat up in speed, the pickup will start forcing the water through the cooler. This is the recommended method of plumbing a PFM intercooler, but not necessarily the only way.

As a side note my machine shop said the Whipple cooler is a super nice piece, but it costs about a grand more then the PFM. Buddy of mine and I run almost identical set ups except for the cooler, and there wasn't a lot of difference on the dyno. Granted we don't boat on a dyno

Craig

Brad Perry

Putting in an intercooler with lower your boost about 1 to 2 psi. That is not all because of physical restriction, it is also because it is doing it's job. Cooling the air makes it more dense and hence you will see a drop in pressure below it. It is a good sign. Even thought the boost drops, you will pick up a few hp. Raising the boost back to where it was gets you the real gains and longevity. The effective compression ratio will be the same as before (which is safe), but the air charge is cooler and denser, which means that you will be even further away from detonation and make more power than before. You might give nickerson a call or Marv at the blower shop. Both have mentioned numbers around 20-30 hp just putting it in, and letting the boost drop. it's when you bring the boost up to previous level that the real gain is realized.

Desktop dyno might be able to give a reasonable, relative comparison. Let me know your specs and I can run it for you.

RumRunner

Contact Marv Hineman @ The Blower Shop. He used to Work for both Weiand, and B&M before starting his own company, he can give you the information you're looking for. www.theblowershop.com

Doug

Brad Perry

He makes a killer intercooler!! (at least it looks that way)

Guy needs a vacation though.

tomcat

Brad

It's interesting that just adding the intercooler adds horsepower. I assume that this occurs without changing timing to take advantage of the lower air temperature.

The drop in pressure in the intake manifold due to the lower air temperature exceeds the resistance of adding the intercooler core, reducing the overall resistance that the blower is trying to overcome as it forces air into the engine. I know that this works with centrifugal blowers, but I always assumed that it wouldn't make any difference to a positive displacement blower, that the only thing really adding any power was the pulley change, and the intercooler just made this feasible by preventing detonation.

Theoretically, a positive displacement blower should always move the same volume of air, just consume more crank power when the resistance is higher. Obviously this isn't the case in real life and it makes sense. There is leakage of air back through the gap between the rotors and the case, and the higher the resistance the more the leakage. Since the blower drive ratio is initialy unchanged, there must be less leakage with the intercooler (more air into engine) to make the extra 20-30 HP.

Blackhawkdn

when you use a blower,the blower adds heat of compression which makes the air and fuel less dense. The intercooler removes the heat of compression making the fuel/air more dense again, allowing the engine to build more power. Example your motor has more power on a cold day then a hot day because of the dense air

Brad Perry

I have no apples to apples real world experience, just before and after tales from Nickerson and Marv. My dyno tests have not experimented with this.

Sounds like positive is relative!

Your logic makes sense and I never really thought about how this happened. Since the air is becoming more dense after passing through the intercooler, the blower would seem to see less restriction and possibly flow a little more (obviously more efficiently) for these gains to be possible. All this without changing any pulley ratios.