Fallstar01

I'd like to better understand this.
If I were to stroke my engine to 5.0, or bore it out to 5.0, Whats the difference in power and torque. Also, How does each one affect the RPM band (assuming the same compression).

If I were to increase compression, how does it affect my power band?

How do cams affect the power band and limits?

Finally, how do valve spring and other head components affect the RPM band and Limits?

Lets say that someone wanted to make an engine that revs up to 9000 rpms(for this example), has a fairly broad (not steeply climing) power distribution and has decent torque, how someone make decisions on the above.

Finally what happens when you throw in factors like
boost/highflowing incoming air vs. restrictive intake
backpressure vs. highflowing exhaust
hot air coming in vs. cold air.
hotter or colder plugs

P Zero

First off, increasing compression naturally doesnt change your power band at all, it just increases power. Cams on the other hand is what decides your powerband, obviously the higher the lift and duration the more power and the worse it idles, and the higher the powerband kicks in. Biggest problem that people come across with cams is they usually put in a cam that can flow more than their heads, which then actually robs you of power. So cam selection is critical.
And makin a streetable 9000 RPM car is hard to do without variable cam timing etc. Dollar for dollar the best thing you can invest into is your cylinder heads, as in getting aftermarket 2 valve heads, they have a overall larger surface area then the 4 valve heads do. The thing that mainly controls how high you can rev your motor is the bottom, if it can handle it is basically the question. More often then not you need forged crank, some good aftermarket con. rods and pistons. Get it balanced and blueprinted boom you can rev as high as your cam will allow. You have to decide how you want to build your motor boost or N/A, turbo or supercharger, or is it gonna be a nitrous car. When you figure out how you wanna do it itll be a lot easier to assemble the motor with the right parts. ANd usually when you increase compression and power, you want a colder plug.

86gt5.0HO

9000RPM's is anything but streetable.

99saleen351r

In stangs anyway

Fallstar01

who said anything about streetable?

Thanks for the info P Zero. Is there anything you can tell me about how stroking the engine affects RPMs/power curve? I'm looking for a nice broad power curve instead of a really steap slope.
Thanks.