| Ubersuber |
09-08-2014 08:27 PM |
Quote:
Originally Posted by MrAnthonyC
(Post 1936885)
Is there any noticeable lag on the tach? Hypothetically, if I was fully depressing the throttle and trying to shift at precisely 7400 rpm, would I shift a moment before the needle hit it, or is the tachometer pretty much exact? I'm a computer guy..i'm used to things lagging behind.. :mad0259:
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You need not worry about overrevving this engine while accelerating up through the gears as the engine is electronically rev limited to 7,400 rpm, and as a bonus it seems the rev limiter is a soft limiter: the engine doesn't so much cut out as refuse to rev any higher. This is a bonus if you unintentionally hit the limiter before you actually shift. The trick is to shift just before the limiter cuts in as hitting the limiter will slow your acceleration runs. Generally I reach for the shifter as the tach passes through 7,000 rpm or so and then by the time the red light begins to flash indicating the rev limiter is about to cut in I can complete my shift.
Do NOT downshift at too high a speed for the gear selected. If you do so you may wreck your engine. There is no protection built in to the car to prevent you from making this mistake (unlike an automatic which usually just beeps at you if you paddle shift down to too low a gear). I'm pretty sure this engine will hold together at 8,000 rpm, maybe only once and I'm only pretty sure. Engines blow up when they are overrevved with the intake valve open on a cylinder. It's the inertia of the piston and connecting rod that breaks the rod or sometimes it's the inertia of the valve and spring that crashes the valve heads into the rising piston, referred to as valve float.
Should you ever sense that you've just selected too low a gear as you let in the clutch pedal shove that left foot to the floor immediately and hope you didn't reach the full rpm for that road speed in that gear. You do get some warning even from an engine that likes to rev this much but it is only a split second before the engine is actually driven to excess rpm by the wheels travelling too fast for the gear you thought you wanted. This is a very rev happy engine whatever the press may say about the noise and torque dips etc. It loves to rev and sounds great while doing it. It isn't a lot noisier at 7,000 rpm than it is at 5,000 rpm.
Learn to shift up aggressively before you learn to downshift aggressively.
Here's the calculated speeds in each gear:
http://www.ft86club.com/forums/showthread.php?t=6325
The spread is a little unusual in that you normally expect a mathematical progression. Why Subaru chose to make fourth closer to fifth and fifth closer to sixth than is ideal is puzzling which then makes the spread from 2 nd to 3rd look odd. This may account for the impression that second gear isn't quite tall enough, or first gear isn't short enough depending on whether 0-60 means anything to you or not. Normally you expect the speed differences as you shift up the box to become wider in nominal numbers: 22/24/26/28/30 would be within the expected range and a progression would be even more logical.
Also, the steps are 22 mph/26 mph/22 mph /22 mph/ and fifth to sixth is not relevant to the discussion because it will be an "overdrive" deliberately selected for fuel economy, this engine won't pull redline in sixth and that is now very usual. |
