slowing down your car using gears V.S using brakes

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Postby FANGIN » Wed Nov 24, 2010 10:34 am

Adamal wrote:Low revs - Engine braking
Medium revs - Squeels the tyres
High revs - Straight compression lock yo!
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Postby Mr. Mainstream » Wed Nov 24, 2010 10:37 am

FANGIN wrote:COMPRESSION LOCK - the best thing about MK2 Escorts

:lol: :lol: :lol:
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Postby BZG Wagon » Wed Nov 24, 2010 3:19 pm

Adamal wrote:Low revs - Engine braking
Medium revs - Engine braking with a brakes to assist
High revs - Brakes with heal-toe to shift down


Summed up nicely :wink:.

Next lesson: rev-changing.

I recall my flatmate compression locking the rear wheels his unwarranted, unregistered Datson 1200 by smacking it into 3rd coming up to a corner in Tauranga. We were trying for 100mph down some of the straights <- another reason why 16 year olds shouldn't be allowed to drive.

Oh and my flatmate had lost his licence for speeding in his WRX. And the Datsun had noooo brakes.
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Postby Tagged » Wed Nov 24, 2010 6:08 pm

ah~thanks guys.

So, its still best to down gear with rev match while trying to slow down right?
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Postby pc » Wed Nov 24, 2010 6:14 pm

Braking while having the car in a suitable gear for the speed you are doing is not engine braking, because the brakes are doing the work.
Slowing down gradually without using brakes while in gear, or limiting your speed while going down hill, while technically is engine braking, I don't view it as such.
To do any real engine braking, you would have to put it into a gear that is too low for the speed that you are doing.

I think engine braking is pointless unless your brakes are not working correctly.
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Postby sergei » Wed Nov 24, 2010 6:55 pm

pc wrote:Braking while having the car in a suitable gear for the speed you are doing is not engine braking, because the brakes are doing the work.
Slowing down gradually without using brakes while in gear, or limiting your speed while going down hill, while technically is engine braking, I don't view it as such.
To do any real engine braking, you would have to put it into a gear that is too low for the speed that you are doing.

I think engine braking is pointless unless your brakes are not working correctly.


not pointless.
Safer.
For example it puts the engine in rpm range to allow you properly abort and escape if needed.
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Postby Bling » Wed Nov 24, 2010 7:09 pm

Only need 1st gear for around town, and open road only needs 2nd gear. I save wear on my other gears. Saves changing gears, and engine braking just comes naturally when you lift your foot off at 8k...... what?..... :lol:
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Postby BZG Wagon » Wed Nov 24, 2010 7:21 pm

pc wrote:Braking while having the car in a suitable gear for the speed you are doing is not engine braking, because the brakes are doing the work.
Slowing down gradually without using brakes while in gear, or limiting your speed while going down hill, while technically is engine braking, I don't view it as such.
To do any real engine braking, you would have to put it into a gear that is too low for the speed that you are doing.

I think engine braking is pointless unless your brakes are not working correctly.


I disagree - for starters you're taking some of the load off the brakes.

As for being pointless - you're not in complete control of the car when you're coasting along in neutral. If something happens (say you lose traction on a corner) there's no way of controling it with the throttle.
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Postby h8wrxs » Wed Nov 24, 2010 7:57 pm

BZG|Bling wrote:Only need 1st gear for around town, and open road only needs 2nd gear.


i agree i used to have a 91 bluebird with a wrecked gearbox that only had 1st and 2nd gear left, it loved doing 95km down the motorway in 2nd gear at like 9000rpm :D

*edit* i should mention i seized the motor in that after about a month

BZG|Bling wrote: engine braking just comes naturally when you lift your foot off at 8k...... what?..... :lol:


how many teeth did u lose on the steering wheel when you let off the throttle at 8k in 1st gear :D
Last edited by h8wrxs on Wed Nov 24, 2010 7:59 pm, edited 2 times in total.
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Postby allencr » Wed Nov 24, 2010 7:57 pm

Sure it's better to put wear on the rings pistons bearings clutch trans U-joints and ring&pinion or CV's then some pads. :D What bullshit!
Of course this doesn't apply to all situations, like needing to save the brakes or just slowing down a gear or two for a corner and not a complete stop.. Too many junior racers out there!

I'll bet that many of the advocates even double-clutch on their up-shifts let alone all their down-shifts. Anyone familiar?
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Postby matt dunn » Wed Nov 24, 2010 8:45 pm

If the question is when slowing to a stop or going down hill should you have the car in gear?

The the answer is yes.


If the question is should you drop it down three gears so it does 7000rpm and you hardly need any brakes at all?

then the answer is no.
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Postby holden_fan2005 » Wed Nov 24, 2010 10:04 pm

Hit first gear in my old barina going down the gorge in Welly.....at 90kph.



Now that was some well proper engine braking. Even lost my oil cap :lol:
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Postby h8wrxs » Wed Nov 24, 2010 10:33 pm

holden_fan2005 wrote:. Even lost my oil cap :lol:



hahahahahahahahahahahahaha im impressed
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Postby ch4ng » Wed Nov 24, 2010 10:49 pm

@holdenfan_2005 did the car survive after that??
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Postby holden_fan2005 » Wed Nov 24, 2010 11:06 pm

It seemed to be fine. Revved to the days but being a light car, slowed down quickly.

Ended up selling it for a grand - bonus! :D
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Postby h8wrxs » Thu Nov 25, 2010 12:04 am

FANGIN wrote:I'v
COMPRESSION LOCK - the best thing about MK2 Escorts


ive never actually unserstood what compression lock was, can someone explain it to me?
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Postby shihad » Thu Nov 25, 2010 1:21 am

http://www.youtube.com/watch?v=IGFeugl4BLg
not the best explanation as its more about how to drift.

but basically its just downshifting aggressively and this locks up the car as the revs spike... from there you can do sweet drifts au .


thats my understanding of it correct me if im wrong.

FANGIN wrote:
COMPRESSION LOCK - the best thing about MK2 Escorts

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Postby h8wrxs » Thu Nov 25, 2010 3:53 am

so does it lock your wheels or does it make you wheelspin?
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Postby RomanV » Thu Nov 25, 2010 7:40 am

It locks your wheels.

Basically engine RPM is at idle or there abouts, and you're jamming it into a gear where it needs to be doing 7000rpm or whatever to match the engine speed.

So either the wheels speed the motor up, or the motor slows the wheels down.

Shift locking in a KP starlet on gravel is possibly the best fun in the whole world.
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Postby spoonza6 » Thu Nov 25, 2010 7:52 am

Tagged wrote:wow looks like im totally wrong on this one haha~
thanks to all your replies!
I only learnt how to drive manual from a friend which learnt from his friend so yea....never really learned how to drive manual properly...lol!


break the cycle hahaha
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