B16A powered CRX

by Eric Bauer

What I did: First gen B16A(1) + SiR ecu + Y1 tranny (w/o LSD) all from a JDMspec EF9 ('90-1 Civic/CRX SiR) swapped into a USspec D15B2 (under)powered '90 CRX Dx.

I thus went from dual-point throttle body injection on the Dx to multi-point injection (as on an HF or a Si). Given the choice any one wishing to have a B16A powered Crx ought to start with an HF or Si to avoid unnecessary headaches.

With that said: Motor, tranny, and ecu are HIGHLY recommended to be bought as a whole (never try to pick one off of here, and expect to find a matching tranny or ecu somewhere else... Not enough 95 Del Sol VTECs in wrecking yards to make this feasible. My whole package came from K Watanabe Importers in SoCal. My swap was supposed to be done by a shop in Orange, CA. I dropped the CRX off on 6/1/97 and was promised it would take two weeks and $2500. Neither turned out true. After two months of incompetence and no progress I towed it out on 8/1 and took on the swap myself.

They hacked my pass side engine mount and rewelded it to fit. Driver side and Rear Motor mount remained stock, they bolted up just fine. Passenger side had to be cut and welded in a different place. Front motor mount gone. As it stands now, the motor is a wee bit fwd and high in the engine bay. What would fix it is swapping my mounts for '90-3 Integra units which I will be doing soon. It does run fine now, although valve cover and hood are in contact as well as my JDMspec (oversized) RS*R headers resting on the front subframe member which at idle gives the car a sometimes not so unpleasant vibrating feel ;)

I have found a professional welder in the meantime. It looks as though I will be doing the following shortly (I have seen it done on another B16A Crx), cut off pass mount and reweld in original location. most likely try to use dynamic's custom adapter mounts, and probably have a front motor mount fabricated by splicing it into the front subframe...

On second thought: probably not! I have heard some people arguing against them. I will replace the bolts that hold my mount to my tranny and get a better (hardened/higher grade) setup.

So yes the B16A1 and Y1 tranny fit inside the engine bay without any dimension problems.

My shift linkage is actually a shortened Integra unit. (We put the Integra one, marked it, cut and rewelded)

My Y1 tranny came sans LSD. It appears as though I may very well have inherited a B16A/Y1 tranny out of the Integra XSi, not the '90-1 Civic/CRX SiR. This doesn't make a difference hp-wise, only confirms the lack of LSD as no Integra XSi came with an LSD (wasn't even an option)

One more thing about trannies, the Y1 is geared for acceleration over top speed (runs at nearly 4K rpm in 5th on freeway at 75-80mph. I have seen a couple Y1s come over from the JDM with bad 2nd or 3rd gears... You can't put in US parts as replacements. There are ways to get the OEM JDM Honda gears and synchros though. Mitch Dunefsky is one of these persons who can order direct from Japanese Honda dealerships. Anyone with a Y1 will be hard pressed NOT to stand on the gas and start smacking through gears. These motor/tranny combos sure do GO!

Clutch is cable, not hydraulic. No difference from Dx there.

Had to swap out throttle cable for a '90 Integra unit. The DX one snaked around the motor nearly one complete time (way too long). The Integra unit needed some modifying as it was still a bit too long (5 inches). Nothing that a bit of creativity and duct tape can't fix...

Drive axles are custom, sadly enough. These are a veritable mix of 92-95 Civic ends, 88 Integra shaft, as well as my CRX pieces - I will have to give you the exact recipe later, don't remember off hand (but has to do with spline count inside my stock DX hub and differing spline count inside the tranny casing of the Y1. The 88 Integra shafts are the perfect length, just have to find the right end pieces to put on...

What else? The JDMspec RS*R header has two O2 sensors, one with a green plug (this is the same one as the US 02 sensor for same year Civics and Integras. And one with a white plug. NOT available in US. Whether they have different resistance and such I don't know, didn't measure them. So I can't tell you if putting two US green ones will work or not. Thing to keep in mind though, the JDMspec ecu does expect two O2 sensors. Stranger still, on my RS*R header they are both located immediately after the first bend coming out of the block, so maybe a max of 6 inches away from the exhaust manifold gasket. They are NOT located on the downpipe as with your standard issue DC or other such aftermarket header. I am also running a Trust S/S exhaust, I did for the time being conserve my stock DX cat sandwiched in between the two. I'll be trying a straight test pipe once road race season gets back underway.

The oil pan on my B16A1 was missing, so I have a 95 GSR one, bolts right up. the headgasket was blown so again 95 GSR. Intake manifold gasket is off of a 95 Del Sol VTEC. Also my motor looked beat up from the outside but super clean on inside, my guess since I have no way of knowing it's exact history is that it might have been raced in its past life in Japan. Also needed a new timing belt: 95 Del Sol VTEC. Be wary of alternator and distributors... they will rust out if they have been sitting in a wrecking yard for a while. And no matter what the Acura/Honda dealership tells you a '90 Integra USspec distributor will not be compatible with the EF9 motor (different crank angle sensor). Alternator may be replaced by Integra model same year. Actually to simplify it, once up and running a '90 Crx (or civic) with a B16A1 is basically as far as the electrical side of things go a '90 Integra with the addition of all the VTEC goodies.

It has been an expensive week:
Previously: headgasket changed
Monday: distributor fried (ignitor wires melted)
Tuesday: timing belt changed, alternator fried
Wednesday: Alternator fried, VTEC solenoid fried
Thursday: VTEC solenoid ordered, throttle cable changed
Friday: VTEC Solenoid replaced

I have the pleasure of telling you it finally is up and running, six months three days after the swap started.

Getting it up and running isn't the end of the saga though. I only run 92 octane chevron supreme. When I started it for the first time it had the stock DX map sensor. The thing was running way too rich. SO much so that it would bog (next to no power) at anything under 3K rpm. What solved this? a '90-3 Integra MAP Sensor from Kelley as well as a FIELD SFC-VTEC controller from Frank Lin. Right now I have it set to their recommended settings: -7% fuel for 1K-3K
-5$ for 4K
0 for 5K (left it at stock)
+15% for 6K
+10% for 7K
0 for 8K

I have VTEC set to turn on at 5K rpm, and off at 7800.

As a result I have noticed a great improvement on my A/F gauge (Cyberdyne), and then obviously behind the wheel... Highly recommended for US users who can't garage 104 Octane 55gal drums of race fuel at home, even if it is pricey at $400+. Forget anything less than 92 octane... Oh yeah ad you'll need to run those expensive Del Sol VTEC PLATINUM NGK sparkplugs...

latest update 4/14/98