By 6,500 rpm, my forged pistons should’ve collapsed, partially bending at least one connecting rod and smashing most of my rod bearings until, finally, that B18C would unwillingly stop spinning as a glorious cloud of oil-and-coolant-packed smoke transcended out of its tailpipe. Things didn’t happen that way, though. Turns out my mid-’90s, makeshift, 400hp B-series wasn’t all that foolhardy.
The Turbo System: The setup began with a T3/T4 hybrid turbocharger that was said to be good for roughly 350 whp, that hung off of an exhaust manifold made of sewer pipe, and that I had no problem spinning well past its purported limit to provoke the power I was looking for. The rest of my forced-induction circus was made up of some sort of entry-level blow-off valve, an internal wastegate, a side-mount intercooler from a Toyota Supra (I think) and intercooler piping made from plain old steel tubing. Later I upgraded to a more competent front-mount intercooler and an external wastegate that put an end to double-digit boost spikes like the smaller internal one was often responsible for.
Engine Management: If I was smart and well-to-do, I would’ve gotten myself some sort of stand-alone engine management system, like Accel’s DOS-based DFI or something from Electromotive. Instead I kept my stock GS-R ECU and backed off my ignition timing a few degrees. The setup was simple but limited just about everything else under the hood. There was also nothing to tune, so the only time I found myself paying the dyno guy was when I wished to see how much power it made as I cranked up the boost controller, which, by the way, was made from leftover air compressor parts.
It was around this time I realized the sorry relationship between Honda’s ECUs and forced induction. They don’t just ignore boost by not recalculating fuel tables or compensating with less ignition timing, they and their MAP sensors also tend to create all sorts of problems once positive pressure’s detected. The solution was obvious: Visit the pet store at the mall. Only there could I find the one-way check valves that normal people use for aquarium maintenance but that I would use to fool my MAP sensor, allowing it to continue to read vacuum but not boost, so that Honda’s ECU could conduct business as usual. A ramshackle setup, to be sure, but it was just about the only solution back then to the odd couple that was Hondas and boost.
The Fuel System: Normally when putting together a proper fuel system, you’ll crunch all sorts of serious equations that, when calculated right, result in the correct size fuel injectors, pump and lines. I’ve got nothing against equations or pretending I’m as smart as the Internet, but the factory GS-R ECU will allow you to run only so much fuel past its injectors and still be able to idle. Instead of running numbers past my calculator, I settled on a wee set of 370cc/min injectors that were fed by a factory pump teamed with some sort of in-line pump that pushed fuel through the Integra’s original lines, filter and rail. All would’ve exploded rather quickly were it not for the boost-dependent fuel pressure regulator, which featured a special diaphragm that increased fuel pressure by a factor of eight for every pound of boost it detected. Brilliant, simple, scary—all at once.
The Bottom End: Ask 1996 what a bulletproof engine’s supposed to look like and get ready to laugh. As you’d expect, this particular engine was made up of low-compression pistons and forged connecting rods to compensate for detonation. Machine shops experienced enough at stuffing ductile iron sleeves into four-cylinder aluminum blocks were sparse, and cylinder braces like block guards were still a year or two away from being invented. Instead, I drilled several calculated, small holes about an inch below the deck’s surface and threaded machine screws into place until they touched the cylinders. The process was known back then as “pinning the block,” and it was every bit as ridiculous then as it sounds now.
The Top End: I wasn’t looking for any more power than what my maxed-out turbo would give me, so the stock GS-R cams were left in place. The rest of the head remained untouched save for a set of dual valvesprings that were added to keep power from dropping off in the upper rpm range under higher boost. Because the ECU didn’t know any better, and severely lean conditions somewhere in the powerband were inevitable, I regularly torched exhaust valves due to high exhaust gas temperatures.
Other Stuff: Clutch technology back then was as antiquated as boost-creeping wastegates and nontunable ECUs. To hold the 400 whp I was hoping for, I went with a six-puck, unsprung-dual-diaphragm setup that was far more aggressive and far less effective than anything today. An OEM flywheel was milled down for further rotational weight savings. Colder spark plugs were added for good measure. All else remained intact.
At just over 20 psi my B-series laid down 420 whp. It idled pig rich, detonated up top and was an all-around sketchy setup that I was never really sure would hold together or not. Sometime later I tore that engine apart for a proper rebuild, complete with an updated engine management system, a sleeved block and revitalized fuel and turbo components for even more power, only this time, not so stupid.