Evian

I recently rode in a 1979 Porsche 928 with automatic transmission in which the owner had a habit of shifting gears from drive to low to make the car go faster. He told me that this practice is normal for Porsche cars. I never heard of this before. I don't do this to mine. I was wondering if what he said is true.

Mark

ummm...maybe QUICKER but not FASTER. A '79 will go about 40-45mph "fast" in 1st...I believe it wil go 'faster' in 2nd and third...


When I AX and DE I 'manually' downshift my car a LOT!

Search the archives - there was a recent lengthy post on 'manually' shifting the auto's.

Jim bailey - 928 International

nope..... just makes a lot of noise and burns up gasoline.The automatic automatically should select the appropriate gear for the situation , if not adjust it . Exception being downhill driving using engine braking or holding a gear through a corner at the limit. Some early 356 engines used roller bearings on the crankshaft and lugging the engine at low speed could damage the engines ,every since Porsche drivers have been reving their engines ......whether they need to or not. The 79 makes peak torque at about 3,500 rpm

Randy V

I agree - dropping the trans into a lower gear via the selector allows you to get up into the max torque area faster than just pushing down on the accelerator to engage the kick-down.

Plus, it's lots more fun to be able to hold first to redline.

Jim bailey - 928 International

Ah Randy in many ways we just said the same thing....... besides no point going to redline if the horsepower is dropping off other than the noise and fun factor .

indefactorX

This is not good for your Automatic transmition due to the way it functions...

You could really badly grind some gears down over time, i've seen ricers in automatics do this alot on the highway and it really tears up their cars, my friend just had his transmition drop on him because he did this alot as well as nuetral drops..

i'd recomend that if you really want to down shift do a manual gear box conversion instead of having to replace your transmition after it's grinded to crap

mspiegle

Is manually shifting down all that different than the kickdown?

928ntslow

I have done this quite a bit with my 3spd 82. I've found that just cruising and everday driving is better to leave it in D and enjoy the drive. It's a 3 spd and the car was designed to do what it needs to do better than you can. If you want to have some spirited fun in the twisties though, then grab the shifter and have some fun. This is the only place where you can do it better and quicker than the car. I have even pulled down to 1st at times to control those hairpins in the canyons of so Cal. You have more control over the car in the curves with the engine braking rather than free wheeling through the turns and riding the brakes...something you will need and don't want to heat up too much. Some say it's a no no, but I say I am willing to absorb the price if I trash the tranny. Lastly, it's a blast to snick through the gears in this situation with more control.

The noise is fun too!...'specially if you have a brola with no cat

G Man

I downshift manually at times if I need to get the car into the powerband without mashing the pedal to the floor. I don't see any harm in the practice as long as you are not abusing the drivetrain.

SharkSkin

The main issue I've heard about with downshifting autoboxes in general is downshifting at high speeds and low engine RPMs. Example, coasting down from freeway speed and dropping it into first. The reason being, the clutches in the tranny are activated by hydraulic servos. The hydraulic pressure is usually provided by a pump on the input shaft. If the input shaft isn't spinning very fast, you may not have full pressure to engage the clutches when you downshift, and that causes a degree of slippage. The slippage can cause the clutches to glaze, causing more slippage... and it's downhill from there.

If you want to avoid premature glazing of this nature, wait until you need power, then downshift under power.

Nicole

Since I got my Jager Engineering Tip Shifter (www.jageng.com), I shift quite often - whenever I feel like I want to be a little more engaged i nthe driving. Expecially I shift back to thrid before turns to slow down and have a little extra power to gt out of that turn. It's fun!

I wish I could do this as nicely with my Saab - it has a four-speed auto that feels like a 5-speed with 4th gear missing. So I find myself often shifting back between D and 3, bu tthe shifter is really clumsy. And because it has a button on it, it can't be replaced easily...

Now, the ultimate treat for us 928 automatic drivers would be a Jager TipShifter of that new generation with the larger button, combined with a secondary kick-down switch - a switch you could just press for short term downshift, or leave in position for longer term spirited driving might be best. Not that I would know...

jserio

Wouldn't add more wear and tear on your cable?