Internal Combustion Engine. Most engines in road going vehicles are 4-cycle internal combustion gasoline engines.

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1answer
107 views

Formula 1 valve trains

There was a statement in a post regarding Formula 1 valve trains being pneumatic or magnetic. Are there valve trains driven magnetically or pneumatically that are on the market? When did they start ...
8
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1answer
79 views

How does Valve Overlap affect emissions?

In this question, it is suggested that valve overlap can affect emissions. In what way can valve overlap affect emissions?
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2answers
425 views

Why do Formula 1 cars use engines with many volumetrically small cylinders?

What's the benefit to Formula 1 using engines like a 3.0L V8 or a 2.4L V8? I read this Reddit discussion on why it's not practical to put small many-cylindered engines into production cars. Cost ...
10
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1answer
59 views

What Can I Learn From Exhaust Manifold Temps?

I was wondering what I can learn from the temperatures on the individual exhaust pipes coming out of each cylinder. The question is general, and my specific example is on my 98 Mazda 626 GF 2L. Last ...
15
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1answer
119 views

Dynamometer Question - How is it operated and what are they doing?

When guys are doing dyno runs they to do it in a gear, interact with the keyboard and then do it again in another gear. It seems they do multiple runs in multiple gears. In this post Paulster ...
8
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1answer
624 views

How to use an engine stand

This is one thing which I have asked many times on a car forum and never received a satisfactory response for. I know that the engine block is somehow bolted onto an engine stand like the one ...
7
votes
2answers
518 views

Two-Stroke Diesel Engine - Do they use forced induction on them?

As I have indicated before, I'm very diesel ignorant. I just know the basics, very basics. In a two-stroke diesel engine using forced induction seems necessary but at the same time I see challenges. ...
6
votes
1answer
158 views

Two-Stroke vs. Four-Stroke Diesel Engines - What is most commonly used in heavy vehicles?

I am not well versed in diesel engines. To prove my point, I've learned in the last month that a two-stroke diesel engine actually exists. My Question. What kind of diesel engine (four-stroke or ...
9
votes
1answer
100 views

What is Lobe Separation Angle (LSA)?

What is Lobe Separation Angle (LSA) and how is it used in camshaft design? How is it measured? What difference does a long or short LSA make?
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4answers
212 views

Cheap vs Expensive Fuels [closed]

What is the difference between the cheapest fuels in a place like Tesco's and the 'high quality', highly priced competitors? Is there actually any noticeable difference in available power, engine ...
5
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2answers
72 views

2004 VW Passat B5 Peculiar Engine Noise

Recently I have noticed that whilst driving there is a very high pitched whining coming from the front of the car. On closer visual inspection with the engine running I opened the bonnet to try to ...
3
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0answers
40 views

Break-in engine [duplicate]

I am going to buy new car Mitsubishi Pajero Sport (Model: MBS MT 4x4). I've heard stories of people 'breaking in' engines for the first few hundred or couple thousand kilometers using methods such as: ...
8
votes
2answers
318 views

Fiat Punto Wont Start. Fuel Light & Three warning lights flashing

My Fiat Punto 1.2 Year 2000 MK2 (I believe) will not start. The engine turns over but the car won't start. The fuel light is flashing and petrol gauge says empty which isn't the case. There are three ...
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4answers
2k views

When does it make sense to replace a camshaft?

Preamble (Rant) I was reviewing this question in which the OP presents a repair quotation that includes replacing the "intake camshaft" to fix an engine that had overheated. To me this ...
3
votes
1answer
277 views

VW Passat B5 EPC Light on Dashboard

There is a yellow light on my dash that says 'EPC'. I have no idea what this could mean on my car as I haven't noticed any difference in the way it drives, nor are there any unusual sounds other than ...
7
votes
1answer
203 views

What should one do to reduce the HP lost at the wheels on an automatic transmission?

I have a 1990 Toyota Supra Turbo 4 speed auto. I've done some research about automatic transmissions and manual transmissions and what are the positives and negatives of each. (For example, MT is said ...
6
votes
2answers
165 views

RPMs jump to 2500 when clutch is disengaged or transmission put in neutral

Good morning all. I drive an 05 Chevy Cavalier, 2.2L, 5-spd manual trans. Lately I've been having issues which I am told is throttle related. As I'm driving for a little bit (time varies) I go to ...
4
votes
2answers
144 views

Engine idle surging on startup & sputters during acceleration

So I don't know anything about cars. But my truck has been having a few problems. It starts up fine and then the idle is really weird, the RPM's surge. The motor keeps bogging down and when you try to ...
5
votes
1answer
65 views

New fuel pump and spark plugs but gas pedal still not responding

I have a Ford Explorer 2007 and I'm experiencing the car cutting out on me. For example, when turning a corner with the engine revs low, the gas pedal wouldn't respond and then the car cut out. It ...
14
votes
3answers
521 views

What is valve float and how does it impact engines?

The Wikipedia entry is hard to grok: Valve float is an adverse condition which can occur at high engine speeds when the poppet valves in an internal combustion engine valvetrain do not properly ...
4
votes
1answer
81 views

Can snowblowers auger belt weaken or is this just wet snow

So I have an old Toro 824 used snowblower from the mid 90's. The last two times I used it we had wet snow. Snow kept getting clogged and I had to break it up with broom and then it would just clog ...
15
votes
2answers
660 views

Why did Ducati decide to use the desmodromic valve train rather than a more tradition valve train?

Ducati's use a unique method to open and close their valves. It's called the desmodromic valve train. The desmodromic valve system does not use springs to close the valve, it uses the cam and has a ...
7
votes
3answers
367 views

Why don't all diesel engines have throttle plates?

I learned recently that many older and some newer diesels don't have throttle plates to control airflow. I was also quite shocked to learn about a condition called diesel engine runaway. Apparently ...
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0answers
46 views

My 94 Toyota 4runner doesn't seem to gain speed even while I'm flooring the gas pedal…whats the issue and how can I fix it? [closed]

94 toy 4runner 6 cylinder. Just replaced sparkplug wires and distributor cap..
7
votes
1answer
147 views

Scatter Camshafts - What are they and why do I want one?

It seems in the world on mini's as in Mini Cooper, there is a camshaft called a scatter cam. It changes the timing for cylinders 2 and 3. I've heard of changing the timing to have 1 and 4 firing at ...
4
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0answers
40 views

Saying its running hot but full of coolant and not over heating

2005 Hyundai Elantra. Says its running hot but has coolant and so far hasn't over heated and also can't turn on heat in car because smoke pours from vents into the inside of car.
5
votes
2answers
66 views

What senses/controls how much fuel is spent for a given RPM?

When maintaining a constant speed on the highway whether up, down or flat the engine still has the same RPM (assuming the incline is shallow enough not to require a gear change) - common sense would ...
4
votes
1answer
85 views

Valve Adjustment - 1975 Harley Davidson Ironhead

On Harley Davidson Ironhead motor (1975 XLCH), how do I adjust the valves? I seem to remember a mechanism in the bottom end but....I can't recall.
4
votes
1answer
90 views

Why do old motorcycle engines rev so slowly?

I know someone with an older Yamaha XS750. It's from the late 1970's. When I rev the engine in neutral it rev's up really slow. It comes down from the revving a slowly as well. When I rev a 2005 ...
4
votes
1answer
101 views

What is causing a clacking knocking like sound on my toyota camry 1999

I got the heads redone by a engine tech, but for some reason after it starts I get this clacking knocking like sound. The timing is correct. I'm assuming the firing order is correct as well, But just ...
6
votes
1answer
182 views

Can diesel engine be harmed as easily as gasoline engine by over-revving?

There is an excellent Q&A about why diesel engines have lower redline RPMs (about 4500 RPM) than gasoline engines (about 6500 RPM). The reason is related to the combustion of diesel fuel. ...
3
votes
1answer
100 views

Top speed of my Bajaj Pulsar 135 is decreased after changing Clutch plate

I would like to know if my clutch plate can be the reason that my top speed is now lower. Top speed of my bike is 115. I drove my bike after the clutch plate replacement and the top speed is now 90- ...
5
votes
1answer
111 views

Is pre-heating a modern engine worth it?

I have a 2011 Toyota Yaris and live in climate where -5C temperatures are common and -20C are not unheard of. The car has an electric engine pre-heater installed. I don't know exactly what is the type ...
10
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1answer
48 views

VW Bora V6 2005 - Sump Replacement Question

My sump cover has a huge hole and I'm going to replace it. Can I take the cover off from underneath the car or does the motor have to be lifted to recover the sump cover?
7
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3answers
152 views

Will an old engine have worse fuel efficiency than a new engine?

I have a gasoline-engine car that is four and half years old and has been driven for 60 000 kilometers. I have noticed that the fuel efficiency is not what it was when the car was new. However, I ...
4
votes
2answers
185 views

Filling gouge on oil sealing surface in aluminum engine block

I bought a 2004 Subaru Impreza Outback Sport (2.5L EJ251 SOHC) a year ago and have found a leaking crankshaft seal. When going in to replace it, I see that the leak is probably caused by a small gouge ...
3
votes
2answers
299 views

Who gets title if you sell a frame and an engine separately

I have a POS (Piece of S**t) salvage motorcycle I purchased cheap for a purpose which has now passed. I'm ready to get rid of it and there's a guy down the street that mentioned possibly wanting to ...
11
votes
2answers
292 views

Diesel Engine Runaway - What is it?

I was watching some youtube videos and diesel engine runaway videos started to pop up where apparently the diesel engine runs out of control until it destroys itself. My Question What is diesel ...
6
votes
2answers
228 views

What's involved in getting a piston engine to spin the other way?

I've been thinking about this problem ever since I had to slightly crank my BMW's engine the opposite way to insert a crank-locking pin. What are the fundamental changes required to make an engine ...
2
votes
1answer
57 views

Is the Chevrolet TPI batch fire injection?

I'm looking at a Chevy Tuned Port Injection (TPI) system from a 91 Camaro Z28 with a 350 cubic inch motor. Is the injection on this batch fire (fires all injectors at the same time regardless of the ...
6
votes
2answers
165 views

Engine continues to spin after putting in neutral

I have a 2001 Plymouth Neon, it has a manual transmission. Recently the car has started to not stop the engine when I shift into neutral. If I shift into neutral while moving, the engine will rev like ...
6
votes
1answer
703 views

Car leaks oil when driving, Oil from exhaust pipe

Car leaks oil when driving not while parked. The bottom of the vehicle is covered with oil and there's white smoke coming from tail pipe when driving. It sat and there no oil puddle in garage but ...
5
votes
1answer
109 views

oil level on dipstick

Which way should this dipstick be placed? When placed in with the bend facing towards the engine it gives a different reading from when placed facing the opposite way. There is not a great deal of ...
3
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2answers
88 views

What would be better for an engine driving at 60mph or 70mph? I wish to get the most miles out of my engine?

At 60mph my engine revs at 2800RPM and at 70 it's 3200RPM. My qustion is which condition would give the most miles from my engine.
4
votes
1answer
261 views

What are the effects of excessive oil changes on an oil pump? (read description)

I would like to know what the effects on an oil pump are when oil is changed. Obviously after changing the oil filter the engine will run dry without oil pressure for the first few seconds while oil ...
5
votes
2answers
767 views

What is the “dollar bill” test?

One of the questions recently made reference to an exhaust failing the "dollar bill" test. How does one perform it and what does it tell you?
3
votes
1answer
40 views

74 Corvette with slight pop in exhaust

I've got a (new to me) 1974 Corvette with the 5.7 / GM 350 . Dual exhaust. Driver's side exhaust sounds perfect. Passenger's side exhaust has a subtle pop/rattle to it and does not pass the "dollar ...
7
votes
4answers
716 views

2015 Honda Fit iVTEC - Shifted into 2nd Gear at Highway Speeds

I was just driving on the highway and went to pass someone uphill, so I went to put it into 4th gear (from 5th or 6th). I somehow made the mistake of putting it into 2nd and the engine screamed and ...
3
votes
1answer
47 views

What would go into a tranny swap on a modern vehicle

I have a 1999 Isuzu trooper and I have been toying with the idea of doing an engine and transmission swap on it. If all goes well with the engine I plan on getting I would like to replace the ...
4
votes
3answers
150 views

What non-driver, non-terrain factors can affect vehicle miles per gallon?

I've been tracking the mileage on my 2015 VW Golf (a non-intercooled turbo, but not diesel, thank goodness). Of course, my driving habits and highway/city balance influence things greatly, but beyond ...