Supercharger and Intercoolers

The engine utilizes a Harrop supercharger. I, of course, made this decision late in the process which is why the already powder coated rear hoop has been ground and welded. Fortunately, unlike fitting a LS9, the chassis didn't need to be modified. Instead it was a fairly straightforward modification to the cage as can be seen below. You will also note that throttle body was relocated from its stock location.

A filter box will be built such that it can get cold air from the passenger-side rear duct. It's going to be a challenge to get the fuel filler tube routed around the induction tube and the frame.

Intercooler

There is a left and right intercooler. The outlets are really nice CNC machined billet parts. However they came with barb fittings and rubber hoses. Fortunately they are M18 x 1.5 ORBs so it was easy to swap the barbs with -6 AN male adapters.

Reservoir / Swirl Pot

Heat EXCHANGERS

Intercooler Pump

I chose a Peirburg CWA100-3 pump. Tecomotive has lots of information on Peirburg pumps.

• Connector to the CWA100-3 Pump: VAG part number: 4D0971993 (ebay for around $8)

• Connector to the stock harness: TE Connectivity p/n 1-1703494-1 (available on arrow.com for $1.69)

• Pump:

  • Tube OD: 20.0 mm

  • Barb:    22.4 mm

Cog Drive

Notes/Links

• Enhanced Automotive: Billet cog drive/belt for Harrop

• ATI Supercharger Super Super Pulley
  
  

Notes

• LS series FDFI supercharger kit

• Increasing Serpentine Blower Pulley Grip With Carbinite - Dragzine

• Belt tensioner

  • http://www.thumpracing.com/index.htm#belt_tensioners

Reservoir Location

The plan is to put a custom reservoir in the nose. That keeps the weight up front and lower than it would be if mounted in the tail. In addition, it won’t get heat soaked like it would in the engine compartment assuming that I have a nostril vent to guide radiator out of the nose.

The location of the reservoir is critical to the performance of the system, there are several things in designing a reservoir that must be taken into consideration.

• The fluid should gravity feed your intercooler pump i.e. placing head pressure on to the pump, this keeps the pump constantly primed with fluid.

• The inlet/outlets should be far enough apart so that the entire volume of fluid in the reservoir is used and the fluid isn’t doing a 180 degree turn on itself and not using the entire volume.

• The return inlet should be as high as possible and returning the fluid into an empty void creating a depressurized area so the pump doesn’t have to work as hard, pushing into a pressurized tank will be harder on the pump and reduce the flow rate.

Harrop Instructions

Harrop doesn't provide generic instructions. Instead the instructions I was sent are for  and isntallation into a Holden VE Commodore
and G8 Pontiac. Better than nothing, but not overly useful. Here are some extracts:

• Fill the intercooler system with coolant and thoroughly purge the circuit of air.

  • A corrosion inhibitor should be added to ensure longevity of the system. We recommend any product conforming to GM6277M: organic anti-freeze, anti-boil.

  • Do not run the intercooler pump dry, as it will fail and void its warranty.

  • It is often easiest to connect a small electrical jumper lead from the battery to the input side of the pump fuse to facilitate priming the pump and purging the air.

• Be sure that the system is not exposed to greater than 70kPa (10 psi) as the system has been designed to operate at atmospheric pressures.

• It is imperative that the intercooler pump is primed and the radiator is free from air pockets.

  • One method that has been successful is to fill the system via the return line (the ؾ” hose that attaches to the base of the intercooler coolant reservoir) until the coolant has passed through the entire system and into the reservoir.

  • As the system fills, release the air from the radiator via the bleed nipple at the radiator top.

  • Operate the intercooler pump for several minutes, ensuring there are no leaks and that the air is purging from the system via the coolant reservoir.

  • A strong flow from the two inlet pipes into the coolant reservoir should be visible.

  • The coolant level should be approximately 50mm from the cap sealing face of the reservoir.

  • The level will need to be monitored and replenished during the first few weeks of operation, as some air will continue to be purged from the system.

• According to the LS Instructions "Ensure the MAF Sensor is mounted in the middle of a minimum 6 inch length of 4 inch diameter tube, and is a minimum of 10 inches from the throttle body."

Delta T ETC

Some folks insist, that because of the higher coolant flow velocity (if one use a larger pump), the heat transfer in the radiator or charge-cooler is smaller, because "the heat does not have enough time to convect out of the coolant, because it flows too fast trough HE" . Therefore, they postulate that slowing the flow of coolant is beneficial.
Well, thermodynamics proves them wrong!

The equations cited in this paper http://jullio.pe.kr/fluent6.1/help/html/ug/node245.htm
show the only time dependent element, m=fluid mass flow rate (kg/s), is in the numerator, hence the heat flux q increases proportionally with fluid mass flow rate.

In another words, bigger pump trough-put results in a higher heat transfer and efficiency. Time the coolant remains in the HE doesn't matter!

The same is true for the heat transfer coefficient,

Faster flowing coolant will always have a larger delta T between it and air in a liquid to air HE, especially toward the coolant exiting end of the HE. Q is always greater with a larger delta T. Therefore, faster flow enables more cooling of the coolant in the HE.

Blow Off Valve

Blow off valves are sometimes confused with bypass valves, which in a supercharger, diverts the air back into the engine directly, it doesn’t vent out into the atmosphere. If your supercharger is centrifugal, a blow off valve can be used however you should only use them if your supercharger has a blow-through mass-air meter (mass-air flow, or MAS) installed or your vehicle will suffer performance problems. If your supercharger isn’t a centrifugal one or utilizes a mass-air meter, a blow off valve is pointless. A supercharger typically is always on, and doesn’t need a blow off valve to sense the pressure build up and engage to vent the pressure. Some Roots type superchargers can have a blow off valve installed, but still you would need to have a bypass valve to properly run the supercharger as designed.