do you downshift to first or coast to a stop?
It's probably unnecessary for cruising the strip in Huntington Beach, but when you're going into an off camber decreasing radius turn and lining yourself up for the second apex and you need the power that the car makes at 5k, not the torque that it lacks at 2k, and the whole drivetrain is wobbling around, you do what you have to in order to get it to crank.
Evolving Member
Joined: Jul 2004
Posts: 302
Likes: 0
From: Cincinnati, OH
Evo is my everyday driver. I downshift through ever gear at every stop (never into 1st). It's not hard downshifting mind you, just your basic slowing down and matching-gear-to-speed type downshifting. I'm on the stock clutch at 23K and drove the same way on my previous 2 manual trannie cars. I have never seen any resulting damage from downshifting or heard of anyone who can prove that downshifting was the cause of their driveline failing. In my opinion, coasting and braking to a stop from 50 MPH with no downshifting is just dangerous.
If you are worried about your clutch failing, 1) you have the wrong car, and 2) don't launch.
If you are worried about your clutch failing, 1) you have the wrong car, and 2) don't launch.
Originally Posted by kcross
im glad the double clutching crowed showed up... you guys are aware that these are modern passenger cars and not model t's right? double clutching is completely unnecessary. i guess you guys are just 2fast.
actually... to be more accurate... try doing the above going at 40mph wheels speed while braking.
Originally Posted by 4G63>OOOO
I downshift and engine brake excessively and have never had a clutch wear to nothing.
For what it's worth, engine braking is a bit tougher on the engine itself. Due to the geometry of the crank and connecting rod, the largest force exerted on the rod is at the top of the stroke, and it's a tensile load on the rod. The high vacuum (or more accurately, the low manifold absolute pressure) created by closing the throttle at high revs adds to the tensile load on the rod by virture of the corresponding vacuum in the combustion chamber (primarily during the transision between exhaust and intake strokes), and denies the piston the cushioning effect of the combustion chamber charge during both the compression/power and exhaust/intake stroke transisions.
English version? Bring your car onto the highway and go wide open throttle until about 7k, where I want you to abruptly come off the gas. Feel the whole car say **** you? That's the conrods trying to clearance themselves right out the side of the block. While this is an extreme example, I think that you may get more engine wear by downshifting and engine braking, but it sure does feel good when you get it right!
For what it's worth, engine braking is a bit tougher on the engine itself. Due to the geometry of the crank and connecting rod, the largest force exerted on the rod is at the top of the stroke, and it's a tensile load on the rod. The high vacuum (or more accurately, the low manifold absolute pressure) created by closing the throttle at high revs adds to the tensile load on the rod by virture of the corresponding vacuum in the combustion chamber (primarily during the transision between exhaust and intake strokes), and denies the piston the cushioning effect of the combustion chamber charge during both the compression/power and exhaust/intake stroke transisions.
English version? Bring your car onto the highway and go wide open throttle until about 7k, where I want you to abruptly come off the gas. Feel the whole car say **** you? That's the conrods trying to clearance themselves right out the side of the block. While this is an extreme example, I think that you may get more engine wear by downshifting and engine braking, but it sure does feel good when you get it right!
Last edited by trinydex; Nov 9, 2005 at 02:41 PM.
id actually rather build boost left foot braking in 2nd instead of going in high rpm in first so i have a longer run in 2nd instead of having to shift back up to 2nd. but hey, different strokes... nothing to get upset about.
actually i don't necessarily downshift to first for racing cuz yeah left foot braking in second is prolly a better option unless you're facing the hairpin from hell (which happens). but what i do do it for is when i'm pulling into my garage and i don't wanna stop or slow down to shift into gear, or if i'm looking for parking in 2nd and i see one pop it in first. but in a racing situation you'd prolly NEED to double clutch to not be locked out of first (when facing hair pin from hell)
ill give it to you on the hairpin. however im not sure if you can do it on an evo but... on my corvette you could disable the solenoid that lock the gear out. does it work the same on the evo, and if so who has the part?
i think i might be sticking my foot in my mouth here because i'm not totally positive, but i think the lock out is mostly due to the fact that the first and second gears have 3 synchros... so it's not really an electronic lock out (this was very popular in t56 equipt ls1 and lt1 powered chevies because of gas mileage issues). it's a sort of mechanical lock out that you experience because it takes so much time for the synchros to finish synching... you can sit there and wait for them... but usually by the time they mesh you're already at a very low rpm and wouldn't need them to apart from how much you need them to when putting it in first from a dead stop.
Originally Posted by kcross
id actually rather build boost left foot braking in 2nd instead of going in high rpm in first so i have a longer run in 2nd instead of having to shift back up to 2nd. but hey, different strokes... nothing to get upset about.
Let me get this straight...
You have perfected the concept of left foot braking and yet it is "2 Fast" to double de-clutch?
Double de-clutching allows you to drop to first gear while moving because it brings the transmission up to the same speed as the engine which, if done correctly, corresponds to the speed the car is moving. It is kinder on the syncros if done any time when down shifting -- especially when the transmission is cold.
If one can learn to do it smoothly then why not do it??
Originally Posted by 4G63>OOOO
I downshift and engine brake excessively and have never had a clutch wear to nothing.
For what it's worth, engine braking is a bit tougher on the engine itself. Due to the geometry of the crank and connecting rod, the largest force exerted on the rod is at the top of the stroke, and it's a tensile load on the rod. The high vacuum (or more accurately, the low manifold absolute pressure) created by closing the throttle at high revs adds to the tensile load on the rod by virture of the corresponding vacuum in the combustion chamber (primarily during the transision between exhaust and intake strokes), and denies the piston the cushioning effect of the combustion chamber charge during both the compression/power and exhaust/intake stroke transisions.
English version? Bring your car onto the highway and go wide open throttle until about 7k, where I want you to abruptly come off the gas. Feel the whole car say **** you? That's the conrods trying to clearance themselves right out the side of the block. While this is an extreme example, I think that you may get more engine wear by downshifting and engine braking, but it sure does feel good when you get it right!
For what it's worth, engine braking is a bit tougher on the engine itself. Due to the geometry of the crank and connecting rod, the largest force exerted on the rod is at the top of the stroke, and it's a tensile load on the rod. The high vacuum (or more accurately, the low manifold absolute pressure) created by closing the throttle at high revs adds to the tensile load on the rod by virture of the corresponding vacuum in the combustion chamber (primarily during the transision between exhaust and intake strokes), and denies the piston the cushioning effect of the combustion chamber charge during both the compression/power and exhaust/intake stroke transisions.
English version? Bring your car onto the highway and go wide open throttle until about 7k, where I want you to abruptly come off the gas. Feel the whole car say **** you? That's the conrods trying to clearance themselves right out the side of the block. While this is an extreme example, I think that you may get more engine wear by downshifting and engine braking, but it sure does feel good when you get it right!
EVOlutionary
Originally Posted by EVOlutionary
Actually I tried this. I was kind of surprised when my car said, "Good day sir! Nice to see you again. Ah, looks like you are ready for some spirited driving today. Hold on tight, old chap."
EVOlutionary
EVOlutionary
Evolving Member
Joined: Jun 2004
Posts: 361
Likes: 0
From: Memphis, TN
Originally Posted by Killboy
Those who think compression braking (engine braking) is harmful to the drivetrain clearly have no idea what is going on. With such a small engine, running fairly low compression due to the turbo, it will never put enough strain on the drivetrain to hurt anything. You put way more stress on it accelerating.
Compression braking does not use gas, and it does not wear the engine. It uses the lack of air/vacuum in the pistons to slow things down. No more wear than cruising along at the same RPM.
Compression braking does not use gas, and it does not wear the engine. It uses the lack of air/vacuum in the pistons to slow things down. No more wear than cruising along at the same RPM.
Originally Posted by dsmythe2
By wear to the drivetrain, I mean gearbox, clutch and diffs. Engine braking without a doubt absolutetly causes wear on these parts. Unless you have the need to downshift into a lower gear to exit a corner at a lower speed, or accelerate out of a turn, or keep from lugging up a hill, fine. IF YOU ARE SIMPLY COMING TO A STOP USE THE FRIKKIN' BRAKES, or wear out the aforementioned parts. It's your choice.
The point you are missing is that you should stay in an appropriate gear for the speed you are doing. You have more control when you do this -- period.
Of course there is more wear by slowing down in gear. The question is whether this wear is significant or for that matter relevant. It is lazy and not correct technique to coast to a stop in neutral if indeed that is what you are prescribing.