it is hard to say considering i do not know the specific car, but here are some general mods that will improve general preformance and horsepower....cold air intake, exhaust system, new cam, bigger gears, port and polish heads, supercharge or turbocharge it(this will be pricey $1000+ but will add near 100 more horsepower), new ignition wires(faster throttle response), and the always stated, what you dont need, get rid of. Overall, i suggest getting the cold air intake and exhaust system. these are probably the cheapest and will make your car much more gas effecient and will add SOME horsepower. hope this helped:)
Chip
Researching the horsepower of the Honda XR650 has provided some different results. This could be due to the motor of the specific bike. As a rule the horsepower of the XR650 is 43 horsepower at 6750 rpm's or revolutions per minute.
it makes you exhaust louder or " meaner " and some say it causes an increase in horsepower
130 for 2.2L 4 cyl. engine (the VTEC version available in the EX was 145) Some sources say 135 for standard engine.
You can try to get a bigger carburetor for the bike. The XR80 carburetor will fit with some modifications. Another possibility is to bore the engine out to 90 cc but then you will need a different piston and rings.
A Chevy 305 with a roller cam will have MORE power than a 305 with a flat tappet cam if both are installed in the same engine. The horsepower of any 305 depends on what all is done to the engine. Changing from flat tappet to roller will gain some. There are other ways to increase horsepower and there are other ways to increase torque.
One simple screw on inside of the pipe near the rear shock remove screw. Grab some pliers Nd pull the baffle out of the pipe. Simple as that
the easyest/cheapest solutions: a 4barrel carb a 500-600 use the crank of a ford 302 engine buy some racing headers and maby a exaust use smaller gaskets to increase compression
a K&N air filter will probably help some with Hp and it will also increase your gs mileage!!! good luck!!!
most Hayes or any other auto book will give you wiring diagrams some stock horsepower and torque quotes. actual numbers check consumer reports or a review website.
Honda is one of the best brand in the market. Some of the Honda hybrid cars are Honda Accord, Honda Civic, Honda CR-V which offer very good car features.
Boring out an engine to get more horsepower is a bit of an art form. The actual increase in horsepower will depend on the bore ( the new volume of your cylinders ) and the weight of the car. Keep in mind that when you bore out your motor you are going to have some differences in fuel and air requirements. This means oversize valves need to go in your head or larger injectors and, depending on your ecu and o2 programming, maybe a high performance chip. The actual increase in horsepower is not easily calculated; even with the actual size of the bore and type of car.