I’ve discussed the fact many times about exhaust header overlap and I feel that it’s still a necessity, whether your header uses anti-reversion chambers or not. The header primary tube must be larger than the exhaust port exit, period.

On the intake side, we’re using one of our killer Skunk2 manifolds. We recently flowed the head being used on this project with our single throttle body intake verses a number of different individual throttle body set-ups and the Edelbrock manifold, and we found that our manifold kicked all of their respective asses at every valve lift. We also noted that there was less pressure differential between measuring points with our manifold, translating to better velocity and hopefully a nicer torque curve. Once again, my trusty 64mm throttle body that Russ Collins reworked back in 1997 is being used with this manifold. I’m not going into detail about the manifold’s mods, but there are some pictures of it elsewhere in the article. It weighs 2.3 lbs less than it did when it was stock, if that tells you anything, and we also had to coat the bottom of the plenum and runners with a carbon-filled epoxy to prevent them from sucking shut if the throttle was suddenly closed at high rpm. Sounds scary, right?

We’ve installed some _” vent tubes in the front of the valve cover, which will be plumbed to a second breather tank in front of the engine. These vent tubes must be situated behind the baffle in the top of the valve cover, or you’ll be filling the breather tank up with oil in no time.

There’s another breather tank plumbed from our normal fittings at the rear of the block. It’s simply not possible to have too much breather area on one of these 2-liter N/A engines.

Next step is to remove the engine from it’s stand and mount the clutch / flywheel combination. I’m a bit apprehensive about the operation of this twin disk unit, but we’re going to give it a try. I’m not one to complain too much about delicate clutch engagement, and or difficult transmissions, having learned to drive manual gearboxes in the early 60’s with Jaguar’s old Moss transmissions, which weren’t synchronized! We’ll see how it goes.

Mounting the transmission was easy, however, the casting (brace) that Honda bolts below the clutch housing required major modifications to clear the Moroso oil pan’s corners. 15 minutes with the die grinder “fixed” it. I feel that using the brace to stabilize the transmission (and the block) is extremely important.

That puts us ready to install in the car. We’ve removed the supercharged ITR engine, so the installation should be a bolt-in…..right.

The installation was relatively uneventful, however, we did modify a number of things including John’s header. The secondary tubes and collector hung a little lower than I wanted, so we cut them and re-welded the pieces to raise the collector up closer to the tunnel…..all-in-all a simple affair. We also did some cutting and welding on the Thermal 3” system under the car to align things better with the header’s collector, eliminating the curved section we used with the blower motor’s Kamikaze header.

The primary O2 sensor is actually mounted just aft the collector flange in the housing that connects to the header’s “donut”. Since this is about 10” further aft than the stock sensor position, I lengthened the wires connected to the sensor. While I was at it, I did the same with the wires connected to the secondary O2 sensor.

The B&M straight stick shifter (with my extension) has always bothered me, so I took the opportunity to heat it and bend the portion above the ball back approximately 1.5” for an easier “reach” from my seated position. While we were at it, we also fabricated a clutch pedal stop to prevent the pressure plate from being over-pressed. Remember this clutch only has about 1.5” of pedal travel. I made some major adjustments on the pedals “cut switch” too, so the engine can be started without pushing the pedal too far downward.

Mounting the breather tanks required a couple brackets that we made in about 5 minutes. I used clear tubing on the feeder lines so we could keep an eye on the system’s oil vapor flow.
Strapped for time, I used a stock (the original) ITR induction tube to connect the throttle body to the air filter. We’ll be making a “Thompson Tube” as soon as we have time….and as soon as Doug is finished with his composite Honda body parts experiments.

We also did a lot of work on the front suspension to get it ready for some serious quarter mile “work” in the future with street legal drag tires. Bushings were removed and replaced, shock valving was changed, and the ride height of the car’s nose was increased .5”.

The engine started instantly. I set the engine’s idle timing at 18 degrees and it’s running with the same “hot-rodded” factory ECU we used with the blower combination for the time being. As soon as the engine’s racked up some break-in miles, we’ll switch over to the MOTEC system, similar to the one we use for dyno room engines. Right now, the engine runs great. It cranks a lot slower than the blower engine…might have to do with a few more points of compression.

Drivability is excellent. It makes a lot of torque, once again due to the compression.

It’s got one of the quickest response times I’ve ever seen on a NA street combination. Just breathe on the “loud pedal” and the revs jump instantaneously. Compression and a light flywheel / clutch can be a wonderful thing.

The clutch operation is going to take some time to grow accustomed to with its short pedal travel. It’s pedal pressure feels lighter than the CM Stage 3, or the stocker for that matter, but it really bites hard. All in all, I think it’ll be the hot ticket.

I’ll update the article with driving impressions, dyno numbers, and performance data as the miles permit.