Exhaust Notes

Fuel Rail Science
Are all fuel rails created equal? Fuel consumption and matching it correctly with the air intake has always been something that has plagued my mind. Are fuel rails simply another engine dress-up modification, intended as something cool-looking to hold the injectors in place, or do different fuel rails suit different applications better than others? What would be the best fuel rail for my K20A3 with an AEM cold-air intake?
Dan Creegan, Flushing, New York

We're sorry that fuel rails have plagued your mind for so long, hopefully we can help. High-horsepower engines that consume a lot of fuel will benefit more from a high-volume fuel rail than, say, a bone-stock B16A would. But there's a lot more to it than simply bolting on the rail. You've got to consider the fuel pump, lines, and filter, and injectors too. Increasing the capacity that the rail can hold without doing the same to the filter and lines will help very little. And unless you have fuel injectors that are capable of doing something with all of that extra volume, or a pump that can push it, you're really not getting much more than a shiny chunk of aluminum under your hood. That's not entirely a bad thing though; most aftermarket fuel rails feature NPT or AN ports, which makes external fuel regulators easier to adapt and can often solve tricky engine swap dilemmas. Unless you're pushing some serious power out of your K20A3 though, don't expect any performance gains from one brand to the next, in fact, don't expect any performance gains over your stock one.

All-Motor B
I have a '97 Acura Integra RS. Right now it has the B18B1 engine in it. I'm looking into swapping my head for a B16A, GSR or Type R one. I know the cheapest way would be the B16A but what would I add to get my engine to 220 hp? On my list of things to add is Crower Stage 2 cams, a Hondata S300, a Blox intake manifold, a Megan Racing 4-2-1 header, and 330cc/min fuel injectors. I honestly think that with tuning I could hit 220 hp but would that be to the wheels? Also, I want to make it stick. What is the best LSD for an Integra tranny?
Patrick U., USS Dubuque LPD-8

The main difference between the B16A and the Type R cylinder heads is the hand porting that Honda applied to the Type R's. Honda didn't hog out the ports though, but rather massaged key areas, like the critical bend where air transitions from the ports past the valves. Of course, the Type R head also has a more aggressive valvetrain with higher lift, longer duration camshafts, but you don't care about that since you're talking about the Crowers. The GSR head isn't that much different and will actually yield a slightly higher compression ratio because of its smaller combustion chambers, so choose carefully because, depending on what pistons you're using, you may need that extra compression. You're on the right track as far as bolt-ons go. However, you might want to consider a header that's more specific to your application, like one from HyTech Exhaust or Bisimoto Engineering. Headers like these are based upon years of R&D and dyno science. Don't skimp here; you could have the most sophisticated top end and valvetrain around, but if you can't evacuate what's being burned efficiently, then you're just wasting your time. Oh, and as far as LSDs go, stick with a reputable brand like Cusco, Quaife, or Kaaz and you'll be fine. Proceed with the eBay knock-offs with caution.