Compression braking
01-24-2006, 09:18 PM
#1
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Most of the time when I've read a discussion about engine or compression braking, someone usually suggests that it's bad. But I've never seen any real explanation of why. First, is this true? And if so.... why? An OMP issue? Maybe the design nature of the apex seals, or something else entirely? And I'm especially curious to hear from some of the track guys, as it seems like engine braking would be hard to avoid during a race or serious track session.
01-25-2006, 07:14 PM
#2
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ok which would you rather replace a set of pads that are designed to wear out or put extra stress on the engine on your way to get a gallon of milk?
it isn't a big engine. def not a diesel. car sure as hell isn't too heavy for the brakes. and i ahve no Mt. in florida. will it blow the engine? no. is it "good" for it? prob not. is a good idea on the track but kind of pointless in daily driving, our brakes are good why not use them?
it isn't a big engine. def not a diesel. car sure as hell isn't too heavy for the brakes. and i ahve no Mt. in florida. will it blow the engine? no. is it "good" for it? prob not. is a good idea on the track but kind of pointless in daily driving, our brakes are good why not use them?
01-25-2006, 08:25 PM
#3
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Engine braking is not bad for your car in small amounts. So in the course of daily driving, allowing the car to slow down some due to engine resistance is fine.
However, using it to slow the car on your way to a stop is plain silly. While engine braking is quite useful when towing and you really need to keep the brakes from getting super hot, it never occurs in street driving an FD. It creates extra shifts and clutch engagements that put extra wear on the transmission internals and clutch. Not to mention the extra wear it might put on the engine (I don't know exactly what it does / does not do to the engine).
Brake pads are cheap and easy to inspect, so the only time I'd use significant engine braking is when the brakes aren't going to stop the car alone.
Dave
However, using it to slow the car on your way to a stop is plain silly. While engine braking is quite useful when towing and you really need to keep the brakes from getting super hot, it never occurs in street driving an FD. It creates extra shifts and clutch engagements that put extra wear on the transmission internals and clutch. Not to mention the extra wear it might put on the engine (I don't know exactly what it does / does not do to the engine).
Brake pads are cheap and easy to inspect, so the only time I'd use significant engine braking is when the brakes aren't going to stop the car alone.
Dave
01-25-2006, 08:41 PM
#4
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Something would have to seriously wrong with your engine for any damage to occur , however a great amount of stress is transfered to gear box , diff and clutch. I have been in a car where the driver was using the engine as the brake ( on gravel) after about a dozen or so corners the clutch plate let go (std) .
01-25-2006, 09:05 PM
#5
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Originally Posted by tampaFD' post='796321' date='Jan 25 2006, 07:14 PM
ok which would you rather replace a set of pads that are designed to wear out or put extra stress on the engine on your way to get a gallon of milk?
it isn't a big engine. def not a diesel. car sure as hell isn't too heavy for the brakes. and i ahve no Mt. in florida. will it blow the engine? no. is it "good" for it? prob not. is a good idea on the track but kind of pointless in daily driving, our brakes are good why not use them?
Look cupcake, I think it was an honest question, though maybe it could have been better explained. But if all you have to offer is a sarcastic way of saying "I don't know" you could have avoided humiliating the Florida public schools with your post.
degessaman and Nospig, thanks for a civil answer. FWIW, I don't regularly use the engine to brake. As a matter of fact, I rarely do it. I'm in the habit of bumping it into neutral and just coasting often. My car is mostly stock and I'm a pretty conservative driver. Aside from the drivetrain, I was just interested on any particular stress on the engine internals unique to the rotary. To be truthful, someone asked me and my initial response was "brakes are cheap" too. But it did get me wondering about guys that track regularly.
01-26-2006, 06:51 PM
#6
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cupcake huh? so in your vast reading comprehension skills my post came off meaning "i don't know" ok.
is a good idea on the track but kind of pointless in daily driving, our brakes are good why not use them?
that was unclear? did you want a thorough discussion of what engine wear is? how it happens? you could also hit the brakes hard enough to activate the abs on your way to get that gallon of milk. should we have a discussion on why not to do that aslo?
i just did not think my post was all that sarcastic unless you take offense to the idea of going and getting milk in your fd?
is a good idea on the track but kind of pointless in daily driving, our brakes are good why not use them?
that was unclear? did you want a thorough discussion of what engine wear is? how it happens? you could also hit the brakes hard enough to activate the abs on your way to get that gallon of milk. should we have a discussion on why not to do that aslo?
i just did not think my post was all that sarcastic unless you take offense to the idea of going and getting milk in your fd?
01-26-2006, 09:07 PM
#7
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Originally Posted by tampaFD' post='796621' date='Jan 26 2006, 0651 PM
i just did not think my post was all that sarcastic.....
01-26-2006, 09:14 PM
#8
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just so we are clear. going down a mountain is a good time to engine brake a bit as it will save the brakes from overheating, especially on a large car/truck. if you dont know why diesel engine/compression brake i know a great site google.com. maybe you have never been to florida, but there are in fact no mountains here. and you dont like my post so you make some obtuse remark like my car is on stands?? nice one fruitcake, yes.... fruitcake. since you seems to have a culinary bend to you.
