Project Honda CRX: Part 1

There are a few things that are always true with cars. More power is always better, for example. Less weight, however, is even more important. All horsepower can do is get you into trouble faster. Light weight, however, helps handling, braking and acceleration equally, allowing you to get into trouble, get back out of it, and then quickly stop and park away from temptation.

Lighter cars demand less power, they demand less of their brakes and less of their tires, which ultimately means light weight is contagious, spreading from one component of the car to the next as the demands of inertia are reduced. It is no secret that the champion of lightness in the Honda world is the diminutive CRX. Our choice of a CRX as our newest project car, then, should require no explanation. If you want the ultimate Honda performance car, this is where you should start.

The 1988 CRX debuted alongside the fourth-generation Civic and was therefore among the first cars to use Honda's ingenious new four-wheel, double-wishbone suspension system. The CRX has always been unique in its purity and simplicity. By not even attempting to accommodate more than two people, the CRX was able to make exceptionally good use of its shortened Civic platform. There is plenty of front seat room for six footers, and the rear cargo area is truck-like in its capacity. CRX owners have been known to haul complete engines around in the commodious rear compartment. Light weight was obviously a design priority for the CRX, but as the years passed, marketing demands for a longer list of features and regulatory demands for passive restraints added weight and complexity. Care should be taken, therefore, to get the right CRX when shopping for your hotrod.

The lightest of all CRXs are the HF models. Designed with the singular goal of exceptional gas mileage, the HF is in many ways the low-tech spiritual predecessor to the Honda Insight.

The quest for gas mileage included a hopelessly under-powered engine wheezing out 89 hp at 4900 rpm and putting it to the ground through extremely tall gearing. If you start with an HF, plan on swapping the engine immediately. Every part of the HF's engine is as small and light as possible. The intake pipe could be clogged with a golf ball, the manifold runners are like Slurpee(R) straws and the catalytic converter is nestled up to the exhaust ports--not to improve emissions, but to shrink the heavy, cast iron exhaust manifold. Despite being the same engine family, the HF's engine was 25 lbs lighter than the D16 in the CRX Si. Nothing is impossible, but making power with an HF engine is awfully close.

The quest for mileage also included a comprehensive lightening program. The lightest of all CRXs, the 1988 HF, weighed in at just a hair over 1,800 lbs (with a dry gas tank), almost 200 lbs lighter than the contemporary Si. While this bantam-weight chassis seems like a dream come true, remember that much of this lightness comes from the undersized engine, tiny brakes and light, 13-inch wheels. The HF even went without front and rear anti-roll bars to save weight. Adding performance will naturally involve adding weight. The HF is still the lightest chassis to start from, however, thanks to limited standard equipment (The lack of a sunroof alone saves nearly 50 lbs.), lighter bumpers, a slightly smaller gas tank (by 1.3 gallons), less sound deadening and lighter seats. Because of the skinny, low rolling resistance tires it was equipped with originally, the steering on the HF is actually quicker than on the Si.

The 1988 CRXs are slightly lighter than any of the subsequent years' models, thanks to their conventional seat belts. 1989 and later cars had door-mounted passive restraints that required stronger, heavier doors. The '88 CRX also has a different rear suspension than any other CRX. Honda's unique sort-of-double-wishbone, sort-of-trailing-arm rear suspension uses a toe control link and a compliance bushing in concert to give a passive rear steering effect.

On the 1988 models, the passive rear steering is exceptionally strong, making them extremely nimble. On later years, much of the rear steering was tuned out, bringing handling more in line with conventional front drivers. Many road racers prefer the earlier car's more aggressive handling, but warn that they must be tuned differently. A big rear anti-roll bar that you would use on any other Civic or CRX is an invitation for snap oversteer on an '88. Most CRX experts agree that for a street car, '89 and later cars are preferable.

Also unique to the '88 rear suspension is a rear main lateral link or lower control arm (what you call it depends on whether you consider it a trailing arm or double wishbone suspension) of stamped steel rather than the cast iron arms of later cars. The rear shock attaches to the control arm with an eyelet, rather than the fork used on later cars. The only other U.S.-market Honda to use this style rear control arm is the Integra Type R, though many of the high-performance Japanese models used this rear arm.

The reason this matters at all is the fact the rear shock must be different to accommodate that rear mount. It is much easier to find rear shocks for the later cars. The later control arm, of course, can be swapped in to accommodate newer shocks.

By 1991, the CRX Si had grown to 2,115 lbs--porky, when compared with the original, but still exceptionally light by modern standards. If you intend to drive the car while you modify it or if you want more than just a bare chassis, the Si is the model to choose. The Si came with rear disc brakes (many road racers consider the drums adequate), front and rear anti-roll bars and a non-VTEC single-cam 1.6 making 108 hp at 6000 rpm and an even 100 lb-ft of torque at 5000 rpm. Though far from a powerhouse, the Si engine can be supercharged, turbocharged or otherwise convinced to make power.

The third option is the middle-of-the-road DX model, which has none of the advantages of the HF or the Si. The chassis has not been lightened, but the engine is still hopeless. Using a two-injector throttle body fuel injection system, the DX engine is on the short list of Honda engines without hope.

The Plan After all this, you might expect our project car to be a 1988 HF. If we had been shopping for one, that probably would be our choice, but we didn't shop for Project CRX, it landed in our lap. Our 1990 CRX HF actually belongs to Holley. What does Holley have to do with a CRX? That question had us stumped at first too, but in addition to the Holley fuel pumps, fuel rails, throttle bodies and such, Holley also owns Earls, Airmass, NOS and Annihilator--all companies that make stuff for Hondas. OK, so they can have a CRX. And we can borrow it for a few years.

The car arrived at our door on the back of a trailer--a sign we didn't consider ominous until we tried to drive it. Though it fired up and ran immediately, forward motion occurred on a glacial timescale. Not only was it HF slow, the clutch was so worn out that you could actually put it in first, rev the engine to 5000 rpm and dump the clutch without the slightest shudder or complaint from the driveline. The revs would slowly drop and the car would creep from a stop with the smoothness of an automatic.

As we said, starting with an HF means swapping the engine immediately, so a dead drivetrain only meant we wouldn't get a chance to get familiar with the chassis before we started work. No big deal. The options for engine swaps are nearly limitless, as you should know from the engine swap guide in this issue.

Our plan is to start with a Japanese-spec B16 for the simple reason that they are far more abundant than B18s and they can be made to bolt in with a simple engine mount kit from HASport. A B18 will fit with the same kit, but a different hood is required. Besides, our B16-powered Civic Si project car was stolen last year, long before we had learned everything we wanted to know about the B16. Our CRX can pick up where that car left off.

Before we can get to engine swaps however, a casual glance at our new boarder told us that a visit to the body shop was in order. If we put a B16 in the car as is, there would be a pile of shattered body filler after every burnout.

Cypress Auto Body was our next stop. Cypress Auto Body actually has two shops; one that does standard accident repair and another that does street rods. When looking for body shops, a parking lot full of smooth, shiny street rods is always a good sign that they know how to do quality work. After one look at our new CRX, Tom Rodriguez, owner of Cypress auto body, told us we should have started with a better car. And so we pass that advice to you. If you were actually paying money for a CRX, this would be a bad one. Besides the exhausted driveline, it had a bent wheel, blown shocks, doors and front fenders full of body filler and very poorly repaired accident damage in the front bumper and headlight area.

When removable body panels such as doors and fenders are damaged, it is usually more cost effective to replace them with less-damaged examples than to fix them. This was the case with ours. For straighter doors and fenders, we contacted Honda Auto Salvage, the all-Honda wrecking yard that HASport, our engine mount supplier, sprang from. Not only does Honda Auto Salvage have lots of Honda parts (that's a given), it actually knows what to do with them. Crossover parts are its specialty and we intend to use both its knowledge and its parts to improve our CRX's brakes and suspension once the engine is in place.

Since the front bumper was damaged anyway, we decided to get a Wings West body kit for the car that replaces both bumpers. The Wings West kit is very similar to an old Mugen kit that is no longer available. The difference is the Wings West kit adds a small lip to the bottom edge of both bumpers and the side skirts. We actually hope to use the kit without the side skirts, as they seem like unnecessary extra weight, but they may be needed visually to keep the front and rear bumpers from looking heavy. Mugen does still offer the small rear lip spoiler for the CRX, so we ordered one of those from King Motorsports.

As of now, the CRX is without an engine, the body is mostly straight and it should be wearing a fresh new coat of Type R yellow by the next time you see it. With luck, and a good alarm, we should learn a lot from this car.

Starting with an HF gives you the lightest car, but everything under the hood has to be tossed. Note the damaged front bumper, tweaked core support and misaligned headlights. This is a good example of what to avoid in a used CRX.

Our CRX was in such sad shape that it had to be weighed before and after each trip to keep track of all the parts falling off it.

Our very first modification was this um...elastomeric exhaust locator strap. The HF's exhaust is not actually hot enough to damage our space-age strap.

Most of the wheels were actually round and all of them held air for at least a week at a time!

Once the front bumper was removed, some old welds were uncovered from a previous accident repair. This is another sign of what to avoid when shopping for a used CRX.

We plan to install a twin-cam B16 engine using HASport's engine mount kit. The instructions that come with the kit show two places that must be massaged slightly to clear the larger engine. For obvious reasons, we had Cypress Auto Body make these modifications before painting.

This particular dent is necessary to clear the alternator pulley on the B16.

When we looked at our new CRX, we just saw a sad, old car that really wanted a new engine. When Tom Rodriguez of Cypress Auto Body looked at our new CRX, he saw the sloppy job done by the last body shop. These doors, according to Rodriguez, were not worth the time to repair. We got new used doors and fenders from HASport in Phoenix.

The new used doors required far less work than the original parts.

Before we pump our CRX up to 300 hp and start buzzing around racetracks at 140 mph, perhaps we should make sure the car is actually straight. Cypress Auto Body's frame rack was the little CRX's next stop.

The frame rack looks like an elaborate automotive torture device. Prior to measuring and straightening, the car is lifted onto these stands that clamp onto the rail under the rocker panel.

These jigs are then clamped onto various points at the front, rear and center of the car that are known to be symmetrical about the car's centerline. With these in place, you can simply sight along the pins hanging down under each jig. If they all line up, the car is straight, but if only two can line up at a time, it's time for the chains.

Surprisingly, our car didn't need any straightening, but we wanted to see how it was done anyway. With the lower rocker panels clamped firmly in place, a clamp is bolted onto the front of the car and a big chain attached to a big hydraulic ram yanks things into line. Ouch.