I‘m thinking buying cold air intake for a 93 GMC Jimmy. How much of an improvement would it be? and are there any other benefits besides better mpg, exhaust sound, and added Horsepower?
I have no idea what your mechanical abilities are, but are you sure it's stuck? The pads will always rest against the rotor. It's not like they will pull back into the caliper when you release the lever. I only ask because I knew a guy that thought they should retract and spent a lot of time working on something that wasn't broken.
You did not mention the age of your bike. Most likely cause of your problem is that the piston in your brake caliper gets stuck and won't retract after your release the brake lever. Solution: You have to overhaul your brake caliper. There's lot gunk on the Orings inside the caliper. The drill is: remove the caliper off the fork, do not remove the brake pads but slowly pump the lever so that the piston moves out. Add fluid to the reservoirs. Remove one of the pads, then keep on pumping until the piston pops out. Remove the banjo bolt from the brake hose, do not lose the compression washers (2). Carefully remove the two orings inside the cavity. Pry all the gunk from the canals. I use a dental probe and toothbrush to do this. Rinse with soap and water. Once clean and dry, replace the two orings, use new brake fluid. If the piston is pitted, you might use fine sandpaper to smooth it out. Replace piston into the cavity, use brake fluid to lubricate. Push all the way back. Reassemble and attach to fork. Bleed. This might take time, so you have to be patient. Procedure guaranteed to solve your problem.
Most folks who install a CAI system get WORSE fuel mileage with the CAI. Why? All of those cool intake sounds tend to lead to a heavier foot on the gas pedal and THAT will kill fuel economy faster than just about anything. You might get a tiny increase in horsepower at the top end but any improvement at normal day-to-day engine operating speeds will be miniscule. You'd need a $100,000 chassis dyno to measure the improvement. Altering the intake system won't affect exhaust sounds (assuming that you don't mash it to the floor more often, which you very well might) but may increase intake sounds somewhat.
Well cold air is good to make horse power and burn the fuel better. Here is the fall back on some. Those that air open engine bay heat is not much better than the stock filter in the cold air box. They let more air go through than a stock filter. Free flow air filter can be got to to going your cold air box. It is the best of both world. More horse power and cleaner burn fuel. Yes it will give you a bit better gas mileages. How much better depend on the engine and the state of maintaince it is in. It depend on how one drive as well. Any gain is better than nothing. If it run cleaner it is using the fuel better and take a little less to do the same work. Plus the filter can be cleaned and reused over and over again. So it save you money buying more filters in the further. If you are getting 10 miles per gallion per tank. You will see some increse in the miiles per year. Some will gain more than others. Every little bit help. It help your engine run better. Those that have ii open in the engine bay will give you less because they use engine bay air and the heat of the engine. Not turely cold air. But they are free flow air cleaner and burn the gasages in the engine compartment. They will give less power because the air is hoter. The gain is not per tank. Eack give you a little better milageage. Some are better than other. They require that are kept clean to work right. The cold box is the best ones out there in my book. Cause cold air box get the air from out side the engine bay. It keep it a way from the engine bay heat. The air is much cooler. That is one of the reason they when from oil bath filter and dry filter on top of the air horn in the frist place. To get colder air to the engine to work better with a cleaner burning of the fuel. They add tub to the front of the vehicle and to the air cleaner housing. That brought gas milage up.
Do you even know why CAI works, or at least the theory behind it? Cold air means more oxygen content into the cylinders. That's all well and good. But guess what? To use that increased oxygen, you must burn more fuel. This is the difference between rich and lean. Very generically, 14.7:1 (air:fuel) is normal. If you have more than 14.7 parts of air to 1 part of fuel, the engine runs lean. Not good for emissions, and to the extreme will damage the motor. If you have LESS than 14.7 parts of air to 1 part of fuel, you are rich. Not good for economy, but normally how engines make the most power. Since all fuel injected systems strive for 14.7:1 under normal (non-heavy throttle) conditions, if you get more air into the engine, the computer knows this (why they have an air temperature sensor and an O2 sensor making sure the engine is not running rich or lean) and adds fuel to get it back to 14.7:1. So while you may make more power, you aren't saving fuel, because you can't. You end up with a net gain of 0MPG. By the way, since 1981 GM has used some sort of cold air induction on ALL of their US vehicles. It may be somewhat restrictive (to keep noise levels down) but if it's drawing air from somewhere other than under the hood, it's cold air. My 1985 Cutlass has cold air induction. My 1983 K5 had cold air induction. My 1985 and 1987 K5's have cold air induction. All factory. Hell, my 2004 Hyundai Accent has cold air induction. Manufacturers have known about it for a LONG time.
