kylebb6

Hi all,
H22 jdm swapped lude, bb6 chassi. Have full exhaust system and CAI. Want some more power mods before I take it in for tune, but it's my daily driver.
My big question is, should I do air upgrades such as intake manifold and throttle body before I do fuel rail, pump, injectors, etc.? I'm leaning towards yes for the intake stuff, but I'm running a stock tune.
Sorry if I sound dumb, new to the car scene, especially the horsepower upgrades area.

Aradin

Stock fuel system is more than sufficient for a basic bolt on engine. Upgrades are not needed until you get into forced induction or more serious NA territory like with cams.

An engine is basically an air pump. The more air you can feed it, the more fuel you can burn. Where do you think you should focus your efforts? A naturally aspirated engine can only suck in so much air too, regardless of what you have available for it in the intake manifold.

Quickly though, Skunk2 intake manifold is a waste of money. Euro-R or PCBx are signifcantly better OEM options. Bigger throttle body is a waste of time too and in fact can be detrimental because it slows down the air velocity coming into the engine. All the fuel system upgrades you listed are a complete waste of time and money on a stock NA engine and won't show any gains. Those things should only be done if required because you have a limitation in the system.

Unless you plan to do cams or boost(which I would not recommend if this is your first adventure into car mods), you will see very little gains with any bolt ons. For a stock H22, a good 3" intake, header w/ collector mod, 3" exhaust, and a tune is about as good as it's going to get. Money on other things is better spent elsewhere like gearing, proper tires and suspension, etc.

There's 20+ years of info out there about this chassis and engine platform at this point. I would recommend searching and doing some research.

kylebb6

I understand it’s like a big ol’ air pump, more air and fuel means more power, so that’s the way I was thinking in. I kept doing my research but couldn’t get a straight up answer from forums of any sort. Thanks for the knowledge! Going straight to a tune.

TimiK

oem injector duty cycle is becoming too high with aftermarket exhaust system and intake manifold

motoxxxman

the stock fuel rail is good to over 400hp. There is absolutely no need to replace that below 400hp unless you just want the cosmetic appearance. Same goes for the FPR.

You can replace the fuel pump though, and that would actually be a good idea, no matter what your plans are. If the pump is original, it's obviously old, and possibly starting to lose performance anyway. Your best bet is to go straight for a Walbro 255HP. They're pretty cheap, and great pumps, and will last a long time. And no, you do not need to replace the rail or FPR when you install it.

If you put aftermarket injectors in, you will NEED a tune immediately. So whatever you do, you should not swap the injectors until the car is at the tuner's shop, or right before winching it up onto a trailer to tow to a tuner. You can not drive the car with stock ecu and aftermarket injectors.

Euro R intake manifold will gain mid range torque, but will lose top end HP.
Skunk2 manifold (the regular cheaper one) is junk. You won't gain anything.
The skunk2 race manifold gives minor gains in top end when N/A, big top end gains with giant cams and/or boost, but also costs several grand and LOTS of dyno time to determine the ideal spacer thickness to use for best performance. Wrong thickness actually hurts power.
The best gains you'll get n/a with stock cams or mild aftermarket cams is just modding the OEM intake manifold; gutting the iab plate and webbing in the upper and lower manifold sections. Time and time again, dyno results have proven this to give better gains than pretty much every aftermarket manifold on the market.

Biggest N/A gains come from cams. Do some research, some work well, some don't. They also NEED to be degreed when installed, you can't just slap them in and call it a day.

Tuning almost always gives gains in power and in gas mileage, if tuned well by a reputable tuner. This applies to every setup, even bone stock. And most mods will pretty much require a tune too, except CAI. The key is the quality of the tune though. And LOTS of so called honda tuners are actually quite terrible. So make sure to do plenty of research before choosing a tuner. And do NOT cheap out. Cheap prices are usually a sign of a lazy or inexperienced tuner. The quality of the tune will literally make or break the engine, and the power figures. Also, once you get it tuned, if you change the setup at all, you will NEED to get it re-tuned. So keep that in mind when deciding what to do when. For example, if you slap some exhaust stuff and a CAI on it then get it tuned, if you change or mod the intake manifold you will NEED to get a full re-tune.

And lastly, as mentioned by the other guy above, a larger TB is a waste of money unless you're running big cams. And to be honest, most of the aftermarket TB's on the market are total junk anyway. And the ones that are decent usually require some knowledgable adjustment to get working properly because they are never adjusted correctly out of the box.

Oh, and if you do ever change the injectors, don't skimp on those either. You get what you pay for. Cheap out on the injectors, and it'll run like crap, and be quite difficult to tune, IF it can even be tuned with them. ID and FIC are the only brands I recommend. Or OEM RSX injectors if bought new from a dealer or reputable seller.

Check out Rosko Racing for all your intake manifold needs. No matter what route you take, you will most likely end up getting at least something from him.