Engine, Intake, Exhaust Modifications to your Normally Aspirated Hyundai engine. Cold Air Intakes, Spark Plugs/wires, Cat back Exhaust...etc.

Thermo Block Spacers Aka Phenolic Spacers

Old 06-16-2005, 01:52 PM
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Following is a list of common questions and answers regarding ThermoBlok spacers. If you have others Please feel free to contact me proturbotiburon

Do I need to install gaskets with the ThermoBlok spacers, or do they replace the manifold gaskets?

ThermoBloks should be installed with gaskets, which is why most kits contain extra gaskets for the spacers. Users may elect to apply a "sensor safe" gasket sealant such as Permatex #1 instead.

Won't the additional length/volume added to the intake manifold mess up the power curve (or VRIS valve resonance points)?

The 1/4" (6.35 mm) addition to the runner length will indeed shift the torque curve to the left slightly, about 50 RPM. This has actually been proven to be a benefit as it helps to restore some of the torque lost due to the addition of larger intakes and exhausts. Take a look at the dyno plot on our TECH page (or on your specific vehicle application page) and you will see that although the torque curve is shifted, power is up across the entire power band.

Will ThermoBlok spacers void my warranty?

Although Outlaw Engineering makes no claim regarding the voiding of factory warranties, most dealers take the stance that if the aftermarket part did not contribute to the cause of the failure, it is a moot point. Outlaw Engineering has literally thousands of ThermoBlok spacers in the field and we have never known of any type of failure related to our product. EVER.

Will ThermoBlok spacers cause me to fail an emissions test?

In a word, no. Outlaw Engineering has tested vehicles before and after insulator installations and passed the stringent California State emissions testing. The vehicles that were tested were California emissions vehicles, not federal, and they were inspected by a VERY picky tech inspector at a California authorized Test and Repair facility. The tech would not allow the Hotshot intake on a vehicle even though the law stated that it was acceptable. However, the tech did not notice the intake and throttlebody spacers as they looked like stock equipment. Outlaw Engineering has sold many, many sets to other California residents and has never received or otherwise heard of any smog inspection issues in California or any other state. CARB certification is a hurdle that we may pass in the future. However, Outlaw Engineering makes no claim regarding the results of improperly installed insulators.

Are ThermoBlok spacers reusable?

Yes. spacers that are carefully removed and cleaned may be reused indefinitely.

What are the negative side effects of running with ThermoBlok spacers?

None. Seriously. Outlaw Engineering does not know of any drawbacks to the use of properly installed ThermoBlok spacers. In addition to power increases, we have received reports of better gas mileage, better sounding induction noise, and longer life of underhood components such as hoses do to reduced temperature to name a few.

How thick are ThermoBlok spacers? Will they cause interference problems with other components like strut tower bars?

Outlaw Engineering chose a ¼" thickness for the insulating material as striking the best balance between heat blocking characteristics and the need to fit within today's compact engine bays. Each Outlaw Engineering kit contains all the parts and instructions necessary for making the insulators operational on a stock engine. If you have added aftermarket equipment such as a strut tower bar, you will need to determine if the bar will clear the ¼" shifted manifold. If interference does exist, most bars can be slightly modified to fit with bending or spacers.

Do ThermoBlok spacers come in other thicknesses?

ThermoBlok spacers are completely modular and can be stacked into any thickness of ¼" increments. If you want a hugely thick spacer for your monster motor, please contact us.

I don't feel the need to keep the throttle body cool, can I buy the intake manifold spacers only?

This is a common question made by people that don't fully understand the operation of the system. The throttle body spacer is not meant to keep the throttle body cool, but is meant to keep the intake manifold insulated from the heat of the throttle body. Remember that most throttle bodies are heated by engine coolant to keep ice from forming in cold climates. This heat transfers from the throttle body to the intake so that the intake is now effectively heated from both ends. If we sold intake spacers only, we would only be providing half the system. If you simply must have the manifold spacers only, please contact us.

But I plan to bypass the coolant passage in my throttlebody?

Outlaw Engineering does not feel that bypassing the throttlebody coolant passage is a very elegant solution to throttlebody heat for many users. This often leads to rough idle, increased fuel consumption and possibly higher emissions. Many TB's contain thermosensors that would never reach operating temperature. It is similar to running an old carbureted vehicle with the choke all the time. Also, there truly is the possibility of ice formation in the TB during the colder months without this system. With the addition of an insulator, the vehicle can operate as it was meant to and the intake will remain cooler.

Won't moving the fuel injectors 1/4" mess up the "aim" of the fuel stream and cause driveability and mileage problems? Doesn't the injector have to hit the back of the intake valve perfectly to work properly?

This was an initial concern of Outlaw Engineering also. After investigation, testing, and real world experience, it would seem that injector pulse placement is not as critical as some may feel. For example, most modern 4 valve/cylinder engines have two intake valves and only one injector per cylinder. If you take a look at some of these injectors, many have a "splitter" that breaks the fuel shot into two streams to shoot it in the general direction of the intake valves. Hardly a precision aimed component. There have been racing organizations that successfully move the injectors several inches from the stock position without negative effects. With literally thousands of ThermoBlok spacers in the field, this has never posed a problem.

What about the EGR? Doesn't the hot exhaust gas heat up the intake manifold anyway?

During EGR operation, exhaust gas is fed into the intake during part throttle operation. This is done to dilute the intake charge in order to cool combustion and reduce NOX emissions. The amount of exhaust gas bled into the intake is minimal and does not appreciably heat the intake charge. Additionally, the EGR valve is closed during full throttle and doesn't dilute the intake charge at all. The temperature data on our TECH page speaks for itself.

Now that the manifold is absorbing less heat from the engine, won't my engine run hotter?

The amount of total thermal energy produced by an engine is enormous compared to the amount that is conducted to and radiated by the intake manifold. The vast majority of this heat energy is removed from the engine by the cooling system. If the installation of ThermoBlok spacers causes your engine to run hot, your cooling system is on the verge of complete failure and in immediate need of repair or replacement. Outlaw Engineering has known no instances of increased engine heat do to the installation of spacers.

What about turbo or supercharging?

The tensile strength of the phenolic material is certainly high enough to withstand any level of boost. Remember that the increased pressure of the intake charge is contained within rubber and silicon hoses held with hose clamps. Outlaw Engineering knows of customers that run ThermoBloks in addition to turbo or supercharging.

Can Outlaw Engineering ship overseas?

Certainly! Outlaw Engineering regularly ships to destinations all around the globe. ThermoBloks have gone to places like Australia, Belgium, Finland, France, Germany, Hong Kong, Ireland, Italy, Japan, Netherlands, New Zealand, Northern Ireland, Norway, Slovenia, South Africa, Switzerland, Sweden and the UK to name a few
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Old 06-16-2005, 02:01 PM
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What are ThermoBlok spacers and what do they do?

Outlaw Engineering ThermoBlok spacers are thermal insulating replacements for your stock intake manifold and throttlebody gaskets. Made from a heat blocking phenol resin laminate, ThermoBlok spacers increase power from your engine by keeping the intake cooler.

Key benefits:

» Produces a cooler intake manifold and intake charge resulting in MORE POWER
» A cooler intake charge also reduces the tendency for detonation, meaning ignition timing can be
advanced for MORE POWER
» Almost invisible modification, looks stock for the stealth factor
» Better gas mileage
» Replaces stock gaskets
» Reusable over and over
» No undesirable side effects

Want to know more? Read on…

Most are well aware that the reciprocating internal combustion engine is simply a highly modified air pump. While many avenues exist for boosting the power output of an engine, most focus on ways to increase the volumetric efficiency of the system. Ported heads, larger diameter exhausts, headers, and bigger throttlebodies all serve to decrease airflow resistance. The greater the amount of air that passes through an engine, the greater the power that engine can produce.

FACT: Every 5°F reduction in temperature increases the density of the air and therefore the power by

Why? From chemistry class, we remember PV=nRT, the Perfect Gas Law. This simple equation signifies that the volume of a gas is directly proportional to the temperature of that gas, in this case air. Cold air is denser than hot air. Why is this important to the performance enthusiast? Simple, your engine can ingest more air when it is cooler and denser; more air can be mixed with more fuel, which releases MORE POWER.

For example, a 150hp engine can gain an additional 3 hp for every 10°F the temperature drops. In modern EFI engines, the intake charge is drawn through an intake tube, filter, MAF (or VAF, etc.) and throttle body and into the aluminum intake manifold. The manifold is made up of a plenum and runners that direct the air into the intake ports in the cylinder head. However, during its residence in the intake, the air charge picks up unwanted heat, which increases its volume. By blocking the heat transferred from the engine, ThermoBlok spacers reduce the temperature of the intake manifold and therefore the air entering the engine. This search for cooler air is the reason behind cold air intake tubes, intercoolers, and icing down the manifold between quarter mile runs.

An additional benefit is that cooler air allows an engine to have a higher resistance to knock and ping. The engine computer can then dial in more ignition timing advance and even boost in supercharged applications.

But how do ThermoBlok spacers keep the intake manifold cooler?

Aluminum is a great thermal conductor. As a result, heat is very efficiently transferred from the hot aluminum cylinder head and throttlebody to the aluminum intake manifold. By placing a thermal insulating material between them, this heat conduction can be greatly reduced.

ThermoBlok spacers are made from a laminated phenolic composite with a thermal conductivity of 0.29 W/m*K. Aluminum on the other hand has a thermal conductivity of 150 W/m*K, more than 500 times higher. You must also remember that there is a gasket, commonly steel (20 W/m*K thermal conductivity), placed between the manifold and head. Replacing the 0.025" thick steel gasket with a .250" ThermoBlok thick spacer will conduct an amazing 688 times less heat (yes, that's nearly 70,000% reduction!).

The ThermoBlok spacer material also exhibits high stiffness and compressive strength, can withstand temperatures up to nearly 300°F, and has a thermal expansion coefficient very similar to aluminum to increase sealing capabilities.

Enough talk? Here are the numbers:

Dyno Results

The following dyno plot was taken from a 1994 Ford Probe GT with a 2.5L V-6 engine. The only modification done to the car between runs was the installation of ThermoBlok spacers.

This plot shows an average gain of 5-7 horsepower and 9-11 ft-lbs of torque across the powerband. Each engine and combination of mods reacts slightly differently, but on average, Outlaw Engineering ThermoBlok spacers result in a 3-5% gain across the entire powerband with peaks as high as 10 horsepower and 12 ft-lbs of torque.

Temperature Results

Temperature data was taken using a CPS T200 temperature sensor with a time constant on the order of 5 seconds. An A/D convertor was used for real time data-logging of the readings into a laptop. The vehicle was driven with a speed of 60 mph. Following the driving test, the engine was allowed to idle for a sufficient time to reach the steady state maximum temperature.

Notice that the temperature difference between the intake manifold and the outside air is the same regardless of the ambient conditions. As you can see, the temperature of the intake manifold reached a steady state of approximately 35° F lower with the ThermoBlok insulators than without during 60 mph cruising. During the idle test, the non-insulated engine was nearly 60 °F hotter.

This means that after idling in the staging lines waiting for a quarter mile run, your insulated engine would have an immediate advantage.

Racing Results

Here's an example: One test vehicle (1994 Probe GT) recorded a best of [email protected] mph with a 60' time of 2.209 seconds prior to the installation of ThermoBlok spacers. Following the installation, the best run yielded a 15.262 @89.315 mph with a 60' time of 2.282 seconds. The temperature during both runs was 55°F. To summarize, the car was ~0.1 seconds quicker and ~1 mph faster, all with a .073 second slower launch. According to rule of thumb, it would require approximately 5 additional peak horsepower for the trap speed to increase by 1 mph.

Many people spend hundreds of dollars on performance mods of dubious value. We wanted as much data as possible to show that ThermoBlok spacers really worked.

In summary, it was shown that:

The intake was 35°F cooler at cruise and nearly 60°F cooler at idle.
Engines gain 3-5% power across the power band and up to 10.0 hp and 12.5 ft-lbs of torque.
The test vehicle was 0.1 seconds quicker and 1 mph faster in the quarter mile.
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