<
The torque wrench is one of the most universally useful hand tools available to the home mechanic. These magical little tools take the guesswork out of the amount of twist you’re putting on bolts, greatly reducing the risk of shearing the heads off of them. You can also rest assured that high-torque bolts and lugs are more likely to be close to specifications. Without a torque wrench, 40ft/lbs feels very similar to 80ft/lbs, but can be the difference between a wheel falling off while you’re on the freeway and having an uneventful cruise.
Mechanical torque wrenches come in two flavors:
Beam Style torque wrenches use a beam of spring steel that is bent by the force you put on it. These are accurate enough for most backyard repair and part replacement jobs, and are inexpensive enough that it won’t break your budget. For a first torque wrench, I highly suggest a Beam-StyleTorque Wrench.
Click Style (pictured) torque wrenches use a clutch-style mechanism. These are generally more accurate than beam torque wrenches, but are more expensive because of their complexity. The SK Micrometer Torque Wrench is one of the best feeling torque wrenches I’ve had the privilege of handling.
Photo courtesy of exfordy.
<
Establish Starting Point
As with any project, the first thing you should do is establish your goals. This is going to require a bit of math, but we’re going to determine the ideal target crank hp gain for your vehicle. A good rule of thumb is that every 10hp you make with a gas engine requires a pound of air per minute delievered into the intake manifold. For example, to transform a 100peak horsepower (php) naturally aspirated engine into a 200php turbo engine, you’re going to need a turbocharger capable of flowing 20lbs of air per minute at a realistic boost pressure. You’ll need to compute the basic engine airflow rate in CFM as follows:
Airflow=(cubic inches displacement * rpm * 0.5 * volumetric efficiency(V.E))/1728
The *0.5 is there because a four-stroke engine only breathe every other revolution, while 1728 converts cubic inches to cubic feet per minute
If you were to insert 83 percent for V.E for a typical 2.0L Honda engine’s 122CID * 7000 * 0.5 * .83/1728=247 CFM
At 83 degrees ambient temperature at sea level 247CFM converts to pounds/minute follows: lbs/min=CFM * .07
Therefore 247CFM * .07 = 17.29 lbs of air per minute.
Using this rule of thumb this 2.0l engine should produce approximately 173 NA HP. Now let’s see what we could do with that number using a compressor. (more…)
<
The b16a1 ROCKS.
The b16a1 is the holy grail of CRX motors. It boasts true vtec, aggressive dual overhead cams, a high safe redline, a lsd-equipped close-ratio cable-driven transmission, and a very tuneable ecu. It really is as nice a fit for the CRX as Honda ever made.
All b16 motors are good choices because of the aftermarket available and the near-perfect rod/stroke ratio, but the b16a1 is particularly suited to the ED chassis (88-91 CRX and Civics) because it’s obd0 and uses a cable transmission. If it came from a CRX SiR, the transmission will be LSD-equipped. If it’s from an Integra XSi, it will come without an LSD.
However, there are downsides.
Because the b16a1 was only available in Japan, and was only produced in the CRX and Civic SiR, getting one requires contacting an importer (who will generally buy one from a running car because of modern Japanese smog restrictions). You will not know any of the history of the motor, but if the shop is worth spending time on, they will offer a full test run on the engine (dyno run and leakdown test) to ensure that it’s in working condition.
The other problem that arises is finding replacement parts. The B family of Honda motors benefits from a large aftermarket parts availability, but stock parts are difficult to find because they need to be imported directly.
Final Thoughts
Overall, the b16a1 is a great choice to put in the CRX. As long as you find a reputable dealer that offers a “complete swap” (axles, ecu, wiring harness, intake manifold, throttle body, exhaust manifold, etc) and the motor and transmission are both in good repair, expect to spend roughly $3,000 USD on this swap, assuming you will be installing it yourself.
More Info
That’s just the beginning. There is a wealth of information available for the b16 series. Here’s a good start for your hunt for more:
The torque wrench is one of the most universally useful hand tools available to the home mechanic. These magical little tools take the guesswork out of the amount of twist you’re putting on bolts, greatly reducing the risk of shearing the heads off of them. You can also rest assured that high-torque bolts and lugs are more likely to be close to specifications. Without a torque wrench, 40ft/lbs feels very similar to 80ft/lbs, but can be the difference between a wheel falling off while you’re on the freeway and having an uneventful cruise.
