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-   -   downshift to first gear? (https://rennlist.com/forums/997-forum/873495-downshift-to-first-gear.html)

Saaboteur 05-13-2015 01:44 PM

downshift to first gear?
 
Just for discussions sake – do you ever downshift to first gear on the fly?

I used to do so all the time in my modified Saab Turbo SPG. As part of the modifications, I went away from the standard 5 speed manual transmission to a rally-spec, toughened 4-speed box with taller gears. The old Saab transmission were notorious for exploding when too much power was made with the engines, so I upgraded. The 4-speed was built by a noted Swedish gearbox builder. First gear in the 5-speed was basically useless when the engine was tuned to basically 100hp over stock, so the taller gears in the 4-speed were quite useful. But then that mean for tighter corners in city driving, I’d go into first on the fly.

The 997 has relatively tall gearing, and lately I’ve also taken to shifting into first gear from second, on the fly. Just curious as to others’ experience.

Carmichael 05-13-2015 01:56 PM

I'm gonna be doing a lot more of downshifting to first this autocross season.

In my previous car, an R53 MINI Cooper S, I'd leave it in second gear, even through the tightest corners. A good tune, Quaife LSD and a roots type blower meant I had lots of torque everywhere in the powerband to shoot out of corners. The 997 has more torque, but second gear is a little too long.

I've been practicing downshifting (heel-and-toe of course) to first and it's pretty easy. I should probably upgrade to Numeric cables in the future, too ...

Quadcammer 05-13-2015 02:22 PM

nope, 2nd is the furthest I go while moving.

the gap between 1st and 2nd is big on my turbo, so I just deal with being slightly out of the powerband in 2nd.

jmt053 05-13-2015 02:36 PM

I downshift to 1st all the time. Going to a red light almost stopped, turns green and I downshift. Not a big deal. Just don't like to lug the engine too much.

Quadcammer 05-13-2015 03:19 PM


Originally Posted by jmt053 (Post 12279002)
I downshift to 1st all the time. Going to a red light almost stopped, turns green and I downshift. Not a big deal. Just don't like to lug the engine too much.

I don't think "almost stopped" is what he was referring to.

wc11 05-13-2015 03:48 PM

Nope.
1st is from a dead stop for me.

PTParks 05-13-2015 04:44 PM

IMHO, no first gear until stopped.

Lvt19672 05-13-2015 04:52 PM

I can't engage first gear while the car is moving.

jmt053 05-13-2015 05:48 PM

I'm talking about rolling at 10 to 15 MPH. I'll downshift. As I stated, I don't like the lug the engine. It will get around 2K or lower and I'll downshift.

GrantG 05-13-2015 06:06 PM

When downshifting to 1st while going over 15mph or so, it's nice for the equipment to double-clutch rev match (put it in neutral, release clutch pedal, blip throttle to match revs to road speed, press clutch and select first gear, release clutch and give gas as needed to be smooth).

I'm assuming we're talking 6M here. PDK should downshift to 1st without issue.

Saaboteur 05-13-2015 09:01 PM

6MT discussion for sure. I only downshift to first at pretty low speed, I've never noted it when I do it, but it's gotta be sub 20km/h. Nice to see everyone's comments on it. Lately, evo magazine's discussions about the Porsche's sportscars is that the gearing is too tall. I guess they're built for Autobahn cruising!

BTW, @Carmichael - I had a MINI too, an 02 Cooper S with JCW package. Great handling car. Wish mine had an LSD. I only drove it for about 9-10 months before selling it. Washer fluid tank was waaay too small for winter use, and of course the trunk was laughable, but it was very fun to drive. Loved the supercharger whine. I remember reading an article at about the same time that I initially got the car back in 05 that F1 spark plugs cost about $50-100 each. The previous owner of the JCW (my buddy's uncle) had done a recent service, and the plugs cost $65 each! Nuts.

awrryan 05-13-2015 09:12 PM

Never. And I could not tell you why even if I want to. I was just taught never to downshift into first gear.

Hella-Buggin' 05-13-2015 09:47 PM

I live in a very hilly area and keeping it in second at a decent rpm would require driving at an unsafe speed in some areas. I often do a rolling downshift into 1st gear by first blipping the the throttle to ease it into gear and then blipping again to let out the clutch. It's a little jerky the first few times but you get better at it. I have to easy out the clutch a little slower than a regular rev match shift but I figure I'm at low enough rpm's that any clutch wear is better than lugging the engine up a hill.

GrantG 05-14-2015 12:24 AM


Originally Posted by awrryan (Post 12279959)
Never. And I could not tell you why even if I want to. I was just taught never to downshift into first gear.

All depends on the car and gearing. A well designed racing gearbox uses 1st for the slowest corners and top gear for the fastest straights on a given track (adjust gearing as needed to match track). Some modern street cars can go well over 60mph in first gear too...

yabawdy 05-14-2015 12:36 AM

It's fine to shift to first while moving with rev matching preferably.

In past there were not synchros between 1st and 2nd so many that learned to drive MT before the 80's were taught not to shift to first until stopped:

"The modern cone system was developed by Porsche and introduced in the 1952 Porsche 356; cone synchronisers were called Porsche-type for many years after this. In the early 1950s, only the second-third shift was synchromesh in most cars, requiring only a single synchro and a simple linkage; drivers' manuals in cars suggested that if the driver needed to shift from second to first, it was best to come to a complete stop then shift into first and start up again. With continuing sophistication of mechanical development, fully synchromesh transmissions with three speeds, then four, and then five, became universal by the 1980s. Many modern manual transmission cars, especially sports cars, now offer six speeds. The 2012 Porsche 911 offers a seven-speed manual transmission, with the seventh gear intended for cruising- top speed being attained on sixth."

http://en.wikipedia.org/wiki/Manual_transmission


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