Maximum Downshift Question

[masraum]

svandamme, if you aren't H&T, then what do you do when you get to the end of the straight, need to brake, downshift, and accelerate out of the corner with as little wasted time as possible?

[svandamme]

i have very fast feet
i also tap dance

[masraum]

Do you downshift during braking or after?

[svandamme]

during, my driving instructor has hammered engine braking in my tiny little brain when i was 18... i do admit , that my 911 is a different breed of car ( only had her for 3 months), and it's a lot harder then with my other cars to get things lined up through a corner, but it seems to work out.

edit > for the record that instructor was a friend of the family who had won a bunch of Rally's driving in Group N in 1978 and 1979 so i guess he knew something about it.. ok it wasn't group A or B , but he came first more than once

[ted]

Heel and toe besides helping the car stay balanced also prevents alot of abuse on the gear box and axles.

[jester911]

There is a reason why the tach is in the center of the dash and not the speedo. I don't ever consider the mph when shifting up or down. I am sure that most of you guys are the same. I watch the tach but just the sound of the engine is usually enough to go on when shifting anyway.

[Isabo]

Svandamme: Sorry if I was a bit abrupt. I am surprised h&t, double decluthching etc were not covered. This does not mean they are not valid choices. Nor do I believe they are obligatory for either fast road or competition. I do believe you should learn and master them before deciding to reject them. However, I am not sure how else you could balance engine speed with travelling speed with steering input and then drive smoothly.
Ted: I know that brakes are for braking. But I am past the point of caring what the "book" says is correct. I engine brake, trail brake etc as and when I consider appropriate.
"The car does not care what gear you are in during turn in"? To me that sounds like the logic a proponent of automatic transmissions would offer I think being in the right gear and at the right speed before you start turning in is critical. Whatever, if it works for you its fine with me.
There are lots of driving styles and techniques, one checks them out and uses those that feel right for one.

[Jack Olsen]

Since we've all got opinions: I don't believe it's possible to drive a car to its maximum capability without being able to downshift smoothly, and (three-footed people aside) it's not possible to downshift smoothly, under braking, without having one foot work two pedals.

For street driving, I honestly don't think it's a very important skill to develop -- since I don't think you should be that close to the limits on public roads.

[speeder]

Originally posted by JackOlsen

For street driving, I honestly don't think it's a very important skill to develop -- since I don't think you should be that close to the limits on public roads.

Amen. A rule of thumb that I always use is that if the inside of your 911 stinks of burning rubber on a public road, you're getting the tires too hot.

[masraum]

Agreed, my personal opinion, h&t is a necessary skill when going 10/10ths, otherwise it is not possible to go 10/10ths, also part of what sets a cars attitude through a corner is how much you are on/off of the throttle, and being at too low an rpm due to being in too high a gear will affect that. Of course, if you aren't at or very near the limit it's not important.

[svandamme]

no worries isabo, i didn't think it was that abrupt at all, i do know double clutching, used to drive a truck without synchro's ( an old army truck we used for hauling stuff around in the familly )
i didn't actually reject the heel and toe thing , i just didn't get it , still don't get it completely as untill now i found the fast foot work fully acceptable and completely good enough for my driving, i don't race on the track, don't drive slow either, but my car is a bit to old and out of shape do start pushing the envelope... yet

it has always been my habit to learn the car before pushing the car, i've seen to many people pushing a newly acquired care before they knew it.. and that's when the car demonstrates it's superiority to the driver... and kills said driver...

my current experience is such that i think that it's extremely important to be at the right speed and gear when you turn in , since it's the safest way to exit the turn at an efficient speed. variation might exist, but for the non professional (sponsored) driver, i think it's not worht risking your car for that minute gain in speed.. no use trying to out brake ones own ego on a public road...you can't win if you do

[MRM]

Vic Elford goes into H&T in great detail in his book "High Performance Driving". He explains why it is essential to drive your car at its limits. That being said, I've spent hours reading that chapter of the book and I still can't do it right. I'll figure it out if I spend enough time on a track.

[ted]

[QUOTE]Originally posted by Isabo
Ted: I know that brakes are for braking. But I am past the point of caring what the "book" says is correct. I engine brake, trail brake etc as and when I consider appropriate.

Isabo it is very difficult to debate engine braking in a letter.
Are you saying trail braking is done with the engine?
I prefer to be either on the brakes or on the gas but never slowing via engine braking.

What is correct is what works for you, great. Are your non book techniques based on improved lap times? What are your favorite tracks to race at?

1. Perhaps your 911 may have a marginal brake system which has brakes designed for the demands of the street environment. Brakes like these in longer run sessions may fade away at which time you use whatever you can to slow the car for the corners. In that case you certainly do use engine braking to slow the car, but it’s a last resort.
If at threshold braking with good brakes you are using engine braking too perhaps you have a brake bias issue?
If you are engine braking at the end of a straight and your brakes and brake bias are good I expect you may have time to gain in the braking zones.

2. The car at turn in is not depending acceleration, do you brake turn in? But this thought requires the assumption that gears are used to accelerate.

Don’t confuse throttle steer car control techniques such as pitch and catch with my position of not promoting engine braking to slow a car.

Be very carefull engine braking in corners if the road is wet.

Perhaps we should just agree to disagree.

[smarjoram]

As for the downshift thing - I usually downshift if I want to overtake or pick the right gear for a tight corner. In which case I look at my rev counter and know that down shifting will add about another 1000 revs - if it ends up in the fun bit (3500- 6000) then I'm ok.

[Isabo]

[QUOTE]Originally posted by ted

Originally posted by Isabo
Ted: I know that brakes are for braking. But I am past the point of caring what the "book" says is correct. I engine brake, trail brake etc as and when I consider appropriate.

Isabo it is very difficult to debate engine braking in a letter.
Are you saying trail braking is done with the engine?
I prefer to be either on the brakes or on the gas but never slowing via engine braking.

What is correct is what works for you, great. Are your non book techniques based on improved lap times? What are your favorite tracks to race at?

1. Perhaps your 911 may have a marginal brake system which has brakes designed for the demands of the street environment. Brakes like these in longer run sessions may fade away at which time you use whatever you can to slow the car for the corners. In that case you certainly do use engine braking to slow the car, but it’s a last resort.
If at threshold braking with good brakes you are using engine braking too perhaps you have a brake bias issue?
If you are engine braking at the end of a straight and your brakes and brake bias are good I expect you may have time to gain in the braking zones.

2. The car at turn in is not depending acceleration, do you brake turn in? But this thought requires the assumption that gears are used to accelerate.

Don’t confuse throttle steer car control techniques such as pitch and catch with my position of not promoting engine braking to slow a car.

Be very carefull engine braking in corners if the road is wet.

Perhaps we should just agree to disagree.

I mentioned trail braking with engine braking as some "books", "experts", "instructors" consider them superflous, outdated or wrong. I think trailbraking is more a road than a circuit technique.

I wouldn't describe my driving style or technique as "non-book". I just refuse to be a slave to it. I find that I am faster and smoother when I do it my way. I have driven some circuits you will know such as, Monza, Misano, Brands Hatch, Silverstone and others you probably don't such as Varano, Snetterton and MIRA. This on trackdays and for instruction with cars and motorcycles. My competition experience is with hillclimbs. I'm not much more than a novice but I am not embarassed by my placings and times either. I seem to do best and feel more comfortable when I do it my way.

My car is in excellent shape mechanically even if it looks a bit sad. Basically it's a 71 with mostly SC mechanicals and fibreglass corners. Brakes are fine. But yes I think there is room for improvement when I enter a turn, I'm either braking too early or too late, I'm working at getting this right.

I like to do my braking in a straight line, be in the right gear as I enter a turn and either accelerate through it or go round with a constant throttle.

Engine braking in the wet: my car has about 200bhp, is quite light and fitted with 16X7&9 wheels with slicks (slicks: translation worn out road tyres)- An excellent way to add to my gray hairs

Agee to disagree? Always cool. But I think if we were discussing this in person with cars and road available we would find that our respective views were not that far apart

-Isa

[Danskman]

I can't imagine driving on a track at 10 tenths and not using H&T. I think on the "average" road racing track not using H&T would cost you possibly 3-4 seconds per lap.

I think that a lot of people that drive "fast" on the street think H&T is not really necessary. If you've never driven in a competitive situation on a track, you've never driven at 10 tenths. You may think you have, you may have even crashed on the street thinking you were, but most likely you haven't.

H&T is different with every model car. On some, it's very easy, on others, it's a very difficult skill to learn. Having used H&T for many years, in lots of different street and track cars, the 911 is by far the most difficult car I've ever driven to H&T. I'm still working to master it, and I think it will be a while. I'm sure having fun learning, however!

[ted]

You would think no H&T would cost time...Perhaps those that don't wait to the last second to downshift. Then releasing the clutch at idle so as not to chirp the rear tires and loose time controlling the car from the momentary rear wheel lock up.

At Big Willow one of the fast guys runs mid 120s and does not heal and toe. He recently also had to replace the transaxle twice in one weekend. Related to no H&T?

Isa it would be thrill to drive on some of the historic tracks you mentioned. Yes in person we might be not as far off. If anything perhaps we both demonstrate the confidece in ourselves required to drive at 10/10ths.
Good luck racing.

[mwbaum]

It seems that H and T is most applicable for track and "at the limit" driving? I rev-match and drive quite spiritedly...but am not a race driver and have never tracked my car. I am sure it can be taken to a much higher level then mine (Ive never lost the rear end for example)...but its surprising what performance our cars can put out even w/o knowing the racing techniques...