correct RPM to shift at?

[wantatlc]

so, on my 74 FJ40 with Chevy 350, I have always wondered if there is a way, belief, system, standard at what RPMs to shift at? Since I was a kid, I have kind of followed this 3000 RPM belief. is that sufficient, or some old wifes tale? does it matter? is there a better method to determine when to shift?

 

[Horsehead]

well... for the most accurate you get it dynoed, then shift either where the tourque and horsepower meet or where your torque begins to fall off... but thats more for race stuff... I shift my 327 at 4500 all the time, no biggie... gone all the way to 5200 before when racing.

 

[Poser]

seems fine....

 

[bad_religion_au]

when the valves are floating, it's time to snatch another gear.

 

[camcruiser13]

when i gets to loud

shift

 

[DSRTRDR]

Except for my last two cars, I have never had a tacho (don't have one on the cruiser, either), but I have always driven manual transmissions; I go by ear, and I have never broken a clutch. When I grew up, there were two camps, the one that believes that you should generally drive a car underrevved (relative to optimal fuel economy and performance) the rationale being it would save fuel, I have no idea where that came from, but my driving teacher (mind you 30 years ago) believed this, as does my husband. Then, there are those who think it is better to rev it up to its optimal performance parameters, then shift, and try to keep it at the optimal balance of revs and speed. Ever since I once had a high compression engine, I have tended to be in the latter camp - rev it up. For what it's worth, the cruiser hasn't crapped out on me driving half-way across the country twice, speeds of 75-80mph included. 2F motor, not Chevvy.

 

[Full_M3tal]

When It Starts Cutting Out You've Gone To Far

 

[Full_M3tal]

By The Way Whats Red Line On Your Tach?

 

[andrewfarmer]

I don't think there can be a hard and fast rule that says 'shift at this rpm'. Depends on driving, road, speed, and to many other variables.
If I'm going hard out on road, I shift at around 3500.
Off road - if I'm working it hard I shift at around 6000

on road normal driving, shift at 1500.

For me it's about how loaded the motor is. Going hard uphill, the motor is working, so I'll rev it higher. Cruising along the orad, little load, so the shift point is earlier.

 

[projektdotnet]

when i gets to loud

shift

that's how i drive my 40...also the "engine rumble" when it shakes the vehicle but seems to be quieter than normal...you've definitly gotten close to redline SHIFT ALREADY!!! Frankly just try to keep it back a lil from redline (i like to shift 500RPM before at MOST and keep it down about 2k below redline...my style...so long as it runs who cares?

 

[treerootCO]

when the valves are floating, it's time to snatch another gear.

Heck no! When the valves float, it's time to put some Z28 springs in there

I flattened two cams before I "learned"

 

[PabloCruise]

when the valves are floating, it's time to snatch another gear.

Yep... x2

 

[FJBen]

I usually shift around 2,200 to 2,800 depending on the circumstance...

Like when I'm racing that 94 Civic with NOS, then I'm up to 2,800 grabbing gears...

 

[Rice]

If you have to ask you're shifting too soon.

 

[Horsehead]

Originally Posted by camcruiser13
when i gets to loud

shift

Haha... when i drive my truck ('68 Chevy C10, 327, cammed, holley 670 cfm carb, long pipe headers and flowmaster 70 series) when it gets loud is at idle. It SCREAMS when you're hitting 4500 and it doesn't redline for about another 1300.. So I am very thankful I have a tach, there is no driving that thing based on your ear... If you did that I'd be so paranoid I'd shift at 2000 everytime.