Okay, I'm placing this post for my own enlightenment. Would people please start listing factors affecting redline, and how to raise it? I know the valvetrain has a lot to do with it, but what else? Especially, how does the r/s ratio affect it? As the r/s ratio varries in either direction, what happens to the torque, horsepower and redline? I'm not a newbie to hondas so you can throw technical terms around, this is just one area I'm not that familiar with.

 

Dude, When (if) you get a response to this, let me know... I have a 97 EX Coupe and would love to have the same question answered.

 

First question would be why?

Do you have the parts to require a higher redline?

Powerband would be the first thing that effects where redline should be. From there you work to safely achive the redline you need.

Stroke determines piston speed. And piston speed definitly affects where a cars redline should be.

Rod length in relation to stroke affects sidewall loading, which should also be factored in.

Valve springs are important.

How well the crank is balanced is important.

Generally, an engine with a higher rod to stroke ratio will have a smaller powerband, but will be powerful in that area. Example is a CTR motor. Basicly it is a b18c block with a b16 crank and longer rods. Lower R/S ratio's will loose effectivness at high rpms. Less dwell time for the piston at TDC and BDC.

Wow...I am just rambling!

 

redline is usually 500 rpm past the RPM at which you make peak HP.
i.e. H22A1 190 hp @ 6900 rpm, redline 7400
B18C1 170 hp @ 7600 rpm, redline 8100.