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Engine – Desmogging Your 22R

This image provides the abbreviations and functions of each piece of smog equipment:

The following images show the location of the various smog components. In the first image below, I have crossed off everything you will be removing with desmogging your 22R

The quickest and easiest way to get rid your smog equipment yourself is to hike up your britches and start yanking anything with a vacuum hose attached to it. Be brave, because at first you will second guess everything you should remove.

You do not need smog equipment for your engine to function properly!

Below are items that you can start to tear into first (going counter clockwise), from the top left circle::

  • EGR Vacuum Module and Outer Vent Control Valve.
  • The pesky hard vacuum lines (remove all the vacuum lines attached to it too).
  • Thermo switch
  • Air injection piping (on the exhaust side of the head attached to the headers).

From the far left Circle:

  • Vacuum switch (the High Altitude Compensator will be in this area too if you have one).
  • VSV
  • Reed Valve
  • BVSV (attached to the center hole in the intake side of the head.

You will remove two components from the back of the timing cover. Unfortunately, we do not have pictures of them, but these are the locations of them (they will later be blocked off).

Remove the Thermo switch, vacuum switch and that big obnoxious vacuum hose port fitting from the intake manifold (these will later be plugged too). You can also remove all the factory plugs as these will be replaced with new plugs included in the LC Engineering kit.

This is optional. There is a plate on the base of the intake manifold that has a temperature sensor for the electric choke. We prefer a manual choke simply because manual chokes are far less likely to fail. The LC Engineering plate does not allow you to retain the sensor housing, but will have a fitting for the heater core.

Right now, your engine should be free of the birds nest of vacuum hoses and emissions equipment. Go ahead and remove your headers if you haven't already (you'll probably need a new gasket anyway). If you removed everything then you should have the following left.

  • The core of the motor (block, head, valve cover, timing cover, water pump, oil pump, fuel pump) -Distributor (with no vacuum hoses attached).
  • Intake manifold (bare with no carb, hoses or fittings attached).

It should look a little something like this (if you removed the intake manifold).

If you left the intake manifold on, it should look like this.

This is a good opportunity to clean the gasket surfaces and make sure that everything is removed. Now it's time to reinstall everything. First, water block plates in the LC Engineering Pro Water Block Plate Kit. Two of them go right on the back of the timing cover, you do not have to remove the head to install these plates as seen in the pictures, but make sure that either the gasket is in good condition or use some gasket sealer when installing these plates).

The other plate in this kit goes in the middle of the head on the intake side (Second circle from the right in the pictures below). This was just a mock up, however the intake manifold gasket runs between this plate and the head. Make sure that gasket is good or use gasket sealer.

Also in the above pictures, is the LC Engineering EGR Block Plate Kit (second circle from the left). The intake manifold gasket also runs between this plate and the head, again, check the condition of the gasket or use gasket sealer. The EGR crossover plate can be a challenge to get to with the engine installed, however it can be done. It is located in the rear of the head show below. The kit comes with the gasket and new bolts:

Next is the LC Engineering Water Block Plate Kit (11 Bolt) located under the intake manifold. The elbow fitting supplied with the kit is for your heater core (optional if you choose to keep your heat) and new bolts are included with the kit as well. The factory hard fuel lines will bolt back up if you decide to keep them (recommended). Also in the below picture, you can see the locations of the plugs that come with the LC Engineering Intake Manifold Plug Kit. The far left two plugs were temporarily plugged during my build, but will later be used for the brake booster fitting and the manifold advance to the distributor.

Here is the intake manifold bolted up. Notice the plug locations, the EGR block off plate to the left and the water block plate in the middle of the head. The barb fitting with the yellow arrow pointing to the PCV valve is an option. That particular plate and barb comes with the Weber kit; however, you can use the LC Engineering EGR Block Plate Kit (Carb Manifold Plate) which DOES not have a barb and utilizes a breather filter on the PCV valve (for race applications). We do not recommend using the breather filter on the PCV because it can get messy under your hood really quick if something goes wrong.

Here's a image of the LC Engineering Spiral Adapter for the Weber 32/36. We recommend this, however it's not necessary to desmogging. This pic also gives you more of a close up of the manifold plugs and block off plates.

Now for that Weber! You can use a factory carb, but they are notorious for adjustment issues and they certainly don't increase the power like a Weber. Follow the weber directions for installation.

Your engine should now look something like this. You'll notice there's no vacuum hoses and fuel lines. If you still have some fuel lines and vacuum lines then you didn't read the first step.

Now you can start the plumbing. Run a hose from the PCV valve to the manifold using the barb fitting that came with your Weber (note, if you chose to use a breather filter on your PCV valve then you will be installing that instead).

Install the Holley fuel pressure regulator. You can use the bracket that came with the regulator and mount it to the intake manifold, or run it back to the fender wall. We prefer it this way because it is cleaner and keeps the hoses to a minimum. You will have to use the 3/8" NPT male to 1/4" NPT female reducer fitting to install the gauge and the 3/8" male NPT to 1/4" barb fittings to attach the fuel hoses. Run the Fuel "IN", Fuel "RETURN" and Fuel "FEED" lines as shown below.

Make sure that you have the Fuel "IN" and Fuel "RETURN" lines hooked up properly at the other side of the hard fuel lines under the manifold and at the tank. You will only need about 6 ft of 1/4" fuel hose to do the job.

You now only need two (2) vacuum lines and will use about 6ft of 5/32" vacuum hose.

  1. Main/Port Advance: From the vacuum port on the distributor closest to the radiator to the vacuum port on the Weber.
  2. Sub/Idle Advance: From the vacuum port on the distributor closest to the head to the vacuum port on the intake manifold. For the manifold port, we installed a 1/4" NPT Male to 3/16" barb fitting on one of the existing holes on the intake manfold (temporarily plugged earlier).

Also in the picture below, you can see the 90* barb we installed for a brake booster (you can use the factory barb, but we wanted the hose to be better routed) and the 90* barb for the heater core that comes with the LC Engineering Under Manifold Water Block Plate Kit.

On the exhaust side, you will need to install the LC Engineering Air Injection Block Plate Kit. These plates go on over the hole you have in your headers from where the air injection pipes used to mount. These plates come with new gaskets to install them, however we recommend getting a new gasket for your headers as well.

For the port in your valve cover that sits just behind the oil cap, you can do one of two things, we recommend #2. Don't forget to hook up your heater core and brake booster vacuum afterwards.

  1. Slap a 5/8" inlet breather filter on it and plug the hole in the Weber filter housing.
  2. Run a 5/8" hose from the breather port to the fitting in the Weber filter housing that comes with your Weber.

The vacuum switches and sensor plugs that come from the wiring harness on the passenger side fender wall can either be plugged, or taped off with electrical tape. You can also track all of those wires back to the Emissions Control Computer located on the driver side kick panel and completely remove all of the emissions electronics. It does not hurt to just have the wires and vacuum ports plugged, or taped. The emissions equipment only "communicates" to itself, if there's no emissions equipment, then it's talking to nothing! If you used all the block off plates mentioned above and removed all the smog equipment attached to the engine and manifold then there should be absolutely nothing the cap off.

Its now time to fill your engine with coolant before starting. After you complete your desmogging, you will need to time your engine, and adjust your carb. It will not run properly if you do not do this! The timing for a 22R should be 5*BTDC at 700-950 RPM without the Vacuum advance. Now your engine is officially desmogged!

Installation Notes:

  1. You can make your own block off plates, but we would highly recommend going with LC Engineerings products. They are the front runners in performance Toyota parts and are made with quality parts and service.
  2. Like we mentioned earlier, this can be done with a factory carb in a very similar fashion, however it does not work nearly as well.
  3. The reason we recommend the complete desmogging is due to the fact those little rubber plugs have the tendency to crack and cause vacuum leaks. When somebody mentions "my desmogged truck is running like horrible and won't idle," 50% of the time, it's from those little cracked plugs.
  4. These instructions are for a manual choke. You can desmog with an electric (or "water choke"), however the electric chokes are annoying. You will need to leave the appropriate sensors and wiring attached in order to use an electric choke.
  5. Again, don't be scared... The easiest way to look at it is to remove anything that is not your Weber, intake manifold, head, block, distributor, water pump, timing cover, oil pump, headers and valve cove, but remove anything attached to those parts and cover the hole.
  6. Do not throw away your smog equipment for two reasons. One, you may need it later on down the road. And Two, there are people out there doing the exact opposite of what you are about to do and they would like to have your parts.