motor

1zippo1 · 12-28-2003, 08:23 PM

As some of you know I mostly drive my moms car since I don't own one myself. She has a Toyota Yaris 1.0 69hp. Not a bad car but not a good one IMO either... the suspension is to soft and the engine, well it's a 1liter, need I say more? The Top Gear guys say it's the best small car... but it just isn't sportive enough IMO.

But still you can have some fun with it, it's not a GTI but you can still discover it's limits or slide through some corners when the road is wet.
One of the things I like to do is when I'm driving "fast" is to brake and downshift at the same time, so the revs go back into the higher reagons.
This improves the braking distance and it's quite fun too. But I fear it's not so healthy for the clutch. I don't get the revs to high. I allways try to keep 500rpm beneath the redline when I'm accelerating and 1000 beneath the redline when I'm downshifting. But I notice that when I do it a lot I hear a metalic high noise when the clutch gets to the point where it clutches (or how do you call it in english). Even when I just do it normally the clutch still makes that noise for a few days when I downshifted to much...

Now my question is of course, is this normal? I can make up a few answers myself:

A. Yes any car, the clutch of an M3 would get damaged if you brake by downshifting and letting the revs go high. Even if you keep well beneath the redline.

B. It's a Toyota Yaris 1.0, if I had a WRX or maybe a Yaris T sport (sort of a gti) you could do this

C. No it's not normall when you do the same with lets say a saxo you don't have this problem

stracing · 12-28-2003, 10:02 PM

i think the technique you're talking about is "engine braking"?

1zippo1 · 12-28-2003, 10:13 PM

Thx for the tips. So normally it shouldn't be a problem. I just don't have to go from 5th gear at 2000rpms to 2th gear at 7000rpm... but I don't do that so that isn't why it's making that noise. When I downshift like that I go through all the gears most of the time...

1zippo1 · 12-28-2003, 10:32 PM

It's only when it clutches that it makes that sound and when I keep the pedal at the clutch point (ok not that healty but it's without applying any throtlle) to try it out it makes that same noise... So I'm sure yes. I suppose the clutch just doesn't tolerate much. When I do the same in my fathers car I never had problems... but I don't use it that often.

But thanks for the help, I'll ask it next time when I go to the garage.

takata · 12-28-2003, 11:29 PM

you shd use 'heel-toe' during a downshift
this will result in minimal drivetrain stress and wear

u juz burn alittle more fuel

SFDMALEX · 12-28-2003, 11:50 PM

When you downshift while braking you have to heel-toe or else: You put to much stress on your syncromesh, you can lock up your tyres, and depending on how many gears you shifter you can go way over the redline which is not healthy.

Heel-toe eliminates all of the stress on everything. If you downshift while braking without heel-toeing its not good and very unhealthy.

You can also double clutch, but that requires more skill then heel-toe and is not necesary.

Or you can just learn how to ommit using the clutch and blip the throttle while in neutral on downshifts.

fedezyl · 12-29-2003, 01:36 AM

I broke my dad's third gear synchromesher before I realized how important heel and toeing is, and learned it of course...so yes...you can break something...

1zippo1 · 12-29-2003, 07:19 AM

OK thx for the tip guys but

ops: euhm to be honest I don't exactly know how to perform that heel-toe thing. Is it when you brake with the front of your foot and at the moment when the clutch clutches you give a little throttle with your heel? But for this your pedals have to be aligned good and in the yaris they aren't

The throttle pedal is much lower then the brake pedal and I've just tried it, you can hardly reach it with your heel when braking...

I didn't know this heel-toe manoever was used by so many people. I thought it was just something like left foot braking... not really nessesary.

TT · 12-29-2003, 07:28 AM

Hehe, I often heel-and-toe even while driving around relaxed in town LOL.. I just watched to many Bestmotoring vids I guess, but my pedals are not perfect neither.. that's why sometimes it's more like left part of the foot on the brake, right part on the accelerator... to do a proper heel the "right" pedals

stracing · 12-29-2003, 08:33 AM

i don't heel-toe on everyday driving, only when i go on a circuit. if you're pedals aren't aligned, get some bolt on pedals to assist positioning.

draak666 · 12-29-2003, 08:40 AM

Heel and toeing doesn't work on every car. I first thought it was difficult in my BMW, but when I drove a new Vectra a week ago... That was simply impossible. The pedals were way too far apart. Also I don't use it all the time. It takes a lot of practice too.

Search the net for 'BMW M5 Virtual Driving School'. There's some expanation and also a video on the technique. If you can't find it, let me know and I'll put it on my site.

SFDMALEX · 12-29-2003, 01:37 PM

This is the best picture I found

This technique does take practice. It's not just about blipping the throttle, you have to know how much to blip it and that depends in which gear you are and how many rpms you have dailed in, and how many rpm you need for the next gear... After you learn it, it all becomes second nature and you dont have to think about anything.

What you do with the heel-toe is trying to match the speed of your transmission with the speed of your engine(or more precisly the flywheel). When you are driving at 100km/h in 5th gear at 2500RPM when you downshift to 4th gear this same speed will be achived at 4000rpm. So as you see you need to blip the throttle in order to reach the 4000RPM that are needed for the lower gear. Now this applies to braking also, because while you are braking the RPMs drop and so does the velocity, when you trail brake or just brake in straight line exactly the same situation happens except your working with smaller numbers.

A little tip, when you heel-toe to lets say 2nd gear or even 1st blip the throttle a lot since these gears are very short on most street cars.

Hope that helped.

SamuraiGti · 01-05-2004, 10:56 PM

I don't have a car, I usually ride with my dad's car or my brother's car.

I already tried to do heel-toe in both but it doesn't go.

In the "jeep", the brake pedal goes too deep and gas pedal stays much higher than the break pedal and "far away" from the break. The gas pedal is very tiny, i have to buy some racing pedals.

ChrisAW11 · 01-13-2004, 05:31 AM

Have the same problems with rather nasty pedal positions for heel&toeing in my MR2... So bolt-on pedals can actually solve these issues (throttle a big deal deeper in the footroom than the brake pedal)? I'd expect them to be the cure for pedals that are far away from each other in left-right direction, but can they correct a too big front-rear direction gap as well?

gottacatchup · 01-13-2004, 05:24 PM

as long as u match the revs correctly there should be no problem its just the straight drops that attemps to instantly rev the engine from 1000 to 5000 that will fuck everything