When Do You Shift Into 5th Gear?

[teamfee3]

I agree on the rpms and motors. While different, BMW bike boxer twins do much better being rev'd to higher rpm and seat the rings better and burn less oil. Our techs are always on customers to get the revs up. There is no reason redline shift or higher rpm running will hurt a motor if well cared for, valve adjusted and fluids changed. I see nothing fun or interesting about 3,000rpms, that's for transportation devices, not Porsches or BMWs. With metal and lubricant technologies you can run pretty much anything hard these days without causing problems. Engines wear our true, but the fun is getting there.

[carlosR]

I'm glad for this thread, I was wondering the same thing myself. Good to see all the different views on this too. I like to go through the gears but I agree that sweet sound in 3rd and 4th is music.

[RWebb]

I think Ian is technically correct, but high revs will take a loooong time to reduce the service life on a 911 motor. Longer than I'll be alive.

I don't redline my motor b/c the car likes it, I do it b/c I like it.

Of course, my valve train is good for about 1,500 more rpm above the redline...

[Argo]

Since I installed my cylinder head temp gauge, I rarely get into 5th. It runs noticeably cooler (cylinder heads, not oil temp) in 4th at highway speeds so I tend to keep it there.

Edit: Oil temp has never been a problem; it's never come close to overheating even when thrashed on a hot day.

[lane912]

i have a stock 912 with the 901 trans and 5th is after 4th and gets used on the freeway

[dfink]

Rwebb has better gearing than I do. 5th gear comes along around 118 for me. Seriously though I use 5th all the time on the highway. 65 MPH is around 3000-3100.
I tend to be either all out or conservative. I get my jollies on the track and my sanity on the highway.

By the way shifting from 2nd to 5th on the way to 3rd is OK. shifting from 2nd to First on the way to 3rd is expensive.

5th gear is either an economy gear or the natural progression from 4th if the track is long enough and you come out of the last turn fast enought.

[lucittm]

In my car, I thought the "5" on the shift knob meant that if I needed to be in overdrive for more than five minutes, I should select that gear. Seriously, if there was an economical way to raise the gear ratios in this car, I would do it. Since we don't have an Autobahn here in the USA (although sometimes I think I-70 could qualify) there is no reason to go over 100 MPH. I would much rather convert that horsepower to acceleration.

Mark

[sscates]

Never, got a 4 speed.

[bonkers]

Originally Posted by ikarcuaso

Do you have a rule-of-thumb you follow when deciding when to shift to 5th while driving your 911? RPM, MPH, traffic conditions, target fuel consumption etc.? Let's discuss.

Cruising comfortably on the open road with RPM significantly above 3k in 4th gear, no corners ahead and no intention of executing a maneuver.

[livi]

Above 90 km/h on flat ground for longer stretches.

[ianc]

3200 rpms is NOT high rpms for these cars

I know, that's why I shift there.

but if you think cruising at 3200 is bad, how do you even drive on the Interstate at all?

I cruise at 3200-3400 RPM (traffic permitting).

Driving ALL day long between 3-3.5K is NOT what you are insinuating, and you're simply missing what these cars are all about imo.

My comments were directed at people who make a habit of either never using 5th gear, or redlining on each shift. They seem to do this because either they don't think 5th is necessary, or that the engine 'likes' it (don't really understand that idea...).

If you travel down the road for one mile in 4th, and one in 5th, the engine will (obviously) see more revs in 4th, and hence will receive more wear. It just doesn't make sense to not use 5th if the engine will accept it at the speed you're going. Engine oil temps are lower and fuel economy and wear are reduced.

I'm not saying to drive the car like a granny. I enjoy a pull through the gears as much as the next guy, but staying in a lower gear when it provides no tangible benefits (as some here seem to do) is nonsensical. I make a habit of trying not to abuse fine machinery, and to me, running an engine hard when there's no need (such as highway cruise) is abusing it. The same goes for pulling redline on every shift when you don't need the acceleration for passing, etc.

But, whatever, run it all day long at 6500 RPM if you want. Your engine's rebuild is your own responsibility.

ianc

[KFC911]

Originally Posted by ianc

I cruise at 3200-3400 RPM...

I'm not saying to drive the car like a granny. I enjoy a pull through the gears as much as the next guy, but staying in a lower gear when it provides no tangible benefits (as some here seem to do) is nonsensical. I make a habit of trying not to abuse fine machinery, and to me, running an engine hard when there's no need (such as highway cruise) is abusing it. The same goes for pulling redline on every shift when you don't need the acceleration for passing, etc.

But, whatever, run it all day long at 6500 RPM if you want. Your engine's rebuild is your own responsibility.

ianc

I cruise at the same rpms you do, and the speed I'm going dictates which gear I'm going to be in, typically 3rd with the roads I'm on and speed I drive.

If you don't run through the power band (and it is NOT going to hurt a 911 engine) in each gear, then you're simply missing what these Carreras are all about imo and is certainly not abusing it. It's a sports car, not an F-150 .

Only you have mentioned running all day long at 6500, not I, and I agree, that would be dumb.

As Rwebb indicated, they're meant to be driven, not "pampered", and they'll last a LONG time, properly maintained, and driven in that fashion (as will most cars based upon my experience). These aren't high torque, low rpm American Iron...heck, for some motors, 4-6K rpms isn't even coming CLOSE to being in the power band. We've beat this horse enough, just have different perspectives on what is "abuse", and what is "fun" (yet still prudent) I suppose...be well.

ps: Shifting too early is indeed detrimental to your tranny...cruising at 35 in 5th (not you) is not a good thing, though the Carreras do indeed have the engine torque to do so.

[theiceman]

these things have 5th

[KevinS]

When driving hard I shift my '71 T into 5th at about 110 mph. Around town almost never. On the highway to save gas.

[porsche930dude]

i use fifth all the time. it does kinda suck shifting down to forth though. I know sometimes when im on a long highway haul coming down an off ramp not really paying attention downshifting ill nick reverse sometimes. Hopefully my new gate shift kit will cure that. I know my brother if he had it his way his car would only come with 1st and 5th. Hes got a vw gti 1.8t that he lugs out all the time. In that car hes got the low end power to do it though. Plus hes usto his old 69 nova with a v8. Our porsches like the higher rpms though. I dont think hes ever taken his gti over 5k though. sad

[Emission]

Originally Posted by sscates

never, got a 4 speed.

+1

[JeremyD]

about 3/4 of the way down the back straight at Sebring. But only if I nail 15 and 16 just right.

[Turboo934]

About ten years ago:Beep beep how do I get this thing out of second gear?

[Hugh R]

Originally Posted by livi

Above 90 km/h on flat ground for longer stretches.

That's what like 55 mph?



When I drive up to Palmdale/Lancaster (California High Desert) up the I-14 highway I put it in 5th.

[livi]

Originally Posted by Hugh R

That's what like 55 mph?

55.92 actually..


Edit: Look! Their tounges are sychronized!