Red Line (not oil)

A quick question for the group, What is the red line for the 1600 engine(1971). My bug has an aftermarket tach with an adjustable pointer. Glenn

This usually happens around 5000-5500 rpms, depending on how tired the engine is. It either starts floating the valves, or simply runs out of breath.

Jan

For the less-informed, what does "floating the valves" mean?

Thanks, Ted

Jan Anderss> >

Yeah, it's like the camshaft rotates and the cam lobe pushes the lifter (cam-follower) which pushes the pushrod which pushes the rocker which "rocks" on a pivot point so that the other end of the rocker pushes on the valve which is normally kept in its seat (closed) by a valve spring and the cam continues to rotate and the lifter starts to drop back down off of the lobe and the pushrod follows along and the rocker starts to "rock" back into its original position and the valve starts to close. The valve closing and the rocker rocking back and the pushrod going back down and the lifter going back down are a result of the valve-spring pressure pushing the valve back towards a closed position which pushes the rocker, causing it to rock back and push on the pushrod which pushes on the lifter which follows the cam lobe. But before the valve can get fully reseated, the camshaft has already rotated enough for the cam lobe to start pushing the lifter back up against the pushrod which pushes against the rocker which rocks which pushes the valve back open before it can even get fully closed again. When your valves don't close all the way, you lose power so the engine can't rev past a certain point so in a way, worn-out valve springs are sort of like a built in rev-limiter. I'm sure now that it's all perfectly clear so as always... you know the line. :-P

pointer.

the STOCK induction system will not let you overrev the engine unless you blow a downshift. That is forced overreving and WILL damage something.

Stock engine: redline 5000...keep it under 4500 to be absolutely safe. This limits your top speed to around 82 MPH IIRC.

If you have dual carbs or a bigger carb, the engine will happily rev its way to destruction. If you put dual carbs on, you can buy rev limiters that attach to the dizzy rotor and may save your engine. Don't trust your eye on the tach.

~Anthony