Address reads “555 4th Street · Unit H4-H6 · Cherry Hill, NJ”. The number 555 has been of great historical significance to Subaru’s World Rally efforts. Unit H4-H6 is a play on the engine layout designations (H4 = horizontally opposed 4-cylinder). Last but not least, Cherry Hill, NJ is the home HQ of Subaru of America.

Also available in ash grey.

Price:	$13
Size:	MediumLargeX-Large

Other product images (click to enlarge):

While looking for some heat shielding to add to the pieces already in use, I started considering the bang-for-buck factor of the various products on the market. Previously, I’d just ordered DEI products for no real reason other than familiarity with the brand name. It occurred to me that although all of the manufacturers’ products in this arena seemed to be made of extremely similar material, maybe one of them worked better than the others.

After a few rounds of email to ThermoTec and Heatshield Products (a new name to me, but they’ve been around a long time), I had some similar products in hand to put through some testing. I already had some of DEI’s product to use.

The Combatants

For the testing, I stuck to one category of heat shielding product: sleeving / sheathing.

DEI Heat Sheath

“Heat Sheath is made from a Hi-Temp fiberglass fabric bonded to an aluminized material then sewn into a tube. Designed to slide over wires and hoses this product can be easily shaped to fit the tightest bends. The Heat Sheath will reflect up to 90% of the radiant heat and can insulate against up to 500 degrees direct continuous heat. Easily cut to length with scissors or a sharp knife.”

ThermoTec Express Sleeve

“Thermo-Tec’s new Express Sleeves are just exactly what our customers have been looking for. The new easy to use sleeving is a combination of a high temperature insulation material to a highly reflective mylar foil with a Velcro closure. The sleeving is designed to provide maximum protection for wires, hoses, and cables from the very damaging effect of radiant heat with an easy application. Simply pull apart the material, wrap around the wire, and re-close the sleeving. Express Sleeves reflect over 90% of radiant heat, is fireproof and fire resistant, and just looks good.”

Heatshield Products Reflect-A-Sleeve

“Keep your wiring, fuel lines, brake lines, and cables safe from heat damage. Our heat resistant hook and loop seam makes installation easy. No disassembly required. Trying to protect your wires? Use our sleeve as a high temperature heat resistant wire loom! Use it as a shield for your intercooler or air intake pipes. Reflect-A-Sleeve acts as a thermal barrier capable of reflecting up to 95% of radiant heat away. *Weight*[sic] there is more, a 3′ length our Reflect-A-Sleeve weighs less than 6″ of the old silicone covered stuff. Though it weighs much less, it offers superior heat shield protection. Reflect-A-Sleeve withstands 1100°F continuous of radiant heat and 500°F direct heat. ”

I recently had the pleasure of replacing my throttle body. In the process, I learned plenty about the setup that I can share with you.

Disclaimer: I can only confirm these instructions and torque specs for the 2002-2004 non-STI WRX models. Using these instructions on any other model could be problematic. For instance, I know for sure that the 2004+ STI torque spec for the 4 TB mounting bolts is 1/4th of what it is for the WRX.

The Pieces

• A - Idle Air Control solenoid valve and gasket directly on top of main chamber (2 screws)
• B - MAP sensor located on the top left (2 screws)
• C - Throttle Position Sensor located low on the driver’s side (2 screws)
• D - Coolant line attached to driver’s side with spring-loaded hose clamp
• E - Coolant line attached to bottom side with spring-loaded hose clamp
• F - Throttle body to intercooler hose (2 hose clamps)
• G - Gasket between throttle body and intake manifold

Removal

NOTE: Before you remove anything, it is recommended by Subaru that you prepare to use a replacement gasket for the throttle body.

NOTE: If you remove the Idle Air Control solenoid valve from the top of the throttle body, replace the rubber gasket inside. I didn’t, and sucked quite a bit of coolant into my engine before I wised up — not good.

NOTE: During this job, I tore the heads of two sensor screws due to the force needed to break them free from their factory over-tightened state! Be prepared for some trouble. I ended up having to ride my bike to True Value to find replacements.

Tools needed: 1 rag, pliers, socket wrench, 12mm deep socket, large flat-head screwdriver, 10mm short socket or preferably a 10mm GearWrench (for the 3 breather line screws in the front of the intercooler)

1. Let the engine cool. Your coolant should be cool/warm and no longer under pressure.
2. Remove the intercooler and thoroughly clean the bolts (they will be used in a bit to plug the TB coolant lines)
3. Remove the intercooler-to-TB hose and hose clamps
4. Unplug all 3 sensors (A, B, C)
5. Disconnect the throttle and cruise cables by pulling each spring-loaded assembly toward the front of the car, then pushing the small cylinder at the end of the cable out of its housing. You should see what I am talking about. It is not difficult, and is just like a bicycle’s brake cable set up. Holding the spring-loaded housings for 10-20 seconds while you unlatch the cable can start to become…uncomfortable. You might want to put a work glove on your pulling hand.
6. Using pliers, compress the coolant line hose clamps and slide them down each respective hose about 2-3 inches. Don’t worry, the hose shouldn’t pop off the TB without effort.
7. Now, one by one, remove the 2 coolant lines from the TB. Plug the ends of the hoses with your clean intercooler bolts. Use your rag to dab up any coolant that may have dribbled around - no big deal.
8. Unbolt the 4 bolts holding the TB to the intake manifold
9. Set the TB aside and remove the TB-to-manifold gasket
10. If you’re going to have the TB off for more than 10 minutes or so, I highly recommend finding a very clean rag to stuff in the intake manifold opening. Better safe than sorry.

Installation

Reverse the order of removal, but be very careful not to overtighten any bolts. The torque specifications are as follows:

1. 4 bolts holding TB to intake manifold = 15.9 ft/lb (22 N-m)
2. MAP sensor screws = 1.2 ft/lb
3. Idle Air Control solenoid valve screws = 2.1 ft/lb
4. Throttle Position sensor screws = 2.1 ft/lb

You may need to bleed your coolant system afterward (unlikely).