52
votes
Accepted
What does a water-like drip coming out of the exhaust of the car signify?
It signifies that the car is running absolutely correct. Here is the reason why:
A gasoline (petrol) molecule is made up as such:
C8H18 (or 8 Carbon atoms and 18 Hydrogen atoms)
Energy is obtained ...
- 139k
50
votes
Accepted
What are the benefits of a lightweight flywheel and why aren't they lightweight already?
The main advantage to a lower flywheel mass on race cars is that the reduced mass allows the engine to rev more freely. The overall weight loss to the car is really not the key thing, it's letting the ...
- 9,276
28
votes
What are the benefits of a lightweight flywheel and why aren't they lightweight already?
cdunn's answer is spot on.
To add a bit (especially for cars), in a race car you often want to be dropping from something like 7000 rpm to maybe 5500 rpm (or an even higher band, depending on the ...
- 682
13
votes
What are the benefits of a lightweight flywheel and why aren't they lightweight already?
Physics dictates that rotational inertia impedes acceleration...
which is why a lighter flywheel is considered to be a performance mod
Less rotating mass = more acceleration, if all else is equal
...
- 38.9k
12
votes
Accepted
What is a 6 Pack and will it add performance to my engine?
A six pack usually refers to the Chrysler (Mopar) carburetor setup which is three-two barrel carbs on an intake. You'll most often hear of it as a 440 Six Pack, the 440 referring to the Big Block ...
- 139k
11
votes
Accepted
What are the differences between a wet motorcycle clutch and a dry motorcycle clutch?
I pulled the following information from this site:
Unless you are a professional motorcycle mechanic, you normally can not see whether a motorcycle has a wet or dry clutch just by looking at the ...
- 139k
11
votes
What are the benefits of a lightweight flywheel and why aren't they lightweight already?
The flywheel keeps your engine spinning
The inertia of a flywheel is in direct proportion to the mass of the flywheel.
Newton's first law of motion states, "An object at rest stays at rest and an ...
- 32.7k
11
votes
Accepted
40MPG at 100MPH?
One of the reasons is loads of extra weight added by safety features and options. 8 airbags, 12 speaker stereo, 14 way adjustable seats, tons of insulation all around, power windows, power locks, 18 ...
- 8,393
10
votes
What is the meaning of BHP and torque in bikes or cars?
Torque in a motorcycle
The piston moves up and down, and the force for that comes from the fuel that is burned. Connected to the piston is a rod, the connecting rod, and that rod is connected (with ...
- 221
10
votes
Accepted
What are Performance Camshafts?
A cam...
in its most generic sense converts rotary motion into linear motion or vice versa using solid egg-shaped actuators (lobes)¹.
An engine camshaft...
refers to the shaft which houses a series ...
- 38.9k
9
votes
What does a water-like drip coming out of the exhaust of the car signify?
Every gallon of fuel your vehicle burns produces a gallon of water out of the exhaust. If the weather is cold you will see it as steam. If the rear of the exhaust system is still cold even in warm ...
- 6,749
9
votes
How do you plan an engine build?
bit of a braindump... Hard to get more specific without more specific requirements...
Is this a drag car, track car, street car, daily driver, etc. Basically this will lead you to - where do you ...
- 8,393
9
votes
What are the benefits of a lightweight flywheel and why aren't they lightweight already?
One thing which hasn't been mentioned here about why a lightweight flywheel may not necessarily be a good thing for the street is, just like brakes, the rotational mass of a regular weight flywheel ...
- 139k
9
votes
3 rings vs 4 rings pistons: which design is better?
There are trade offs, so no clear answer here.
First of all, just to be anal and clear something up ... what you have is actually a 4-ring and a 5-ring piston. The oil control ring at the bottom ...
- 139k
8
votes
Accepted
Cheap vs Expensive Fuels
Gasoline is made in large batches. Each batch has a number of attributes that should be met; Octane, specific chemistry, volatility, contaminates, ethanol content, and others. The output is dependent ...
- 11.5k
8
votes
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How does a dynamometer work?
NOTE: The following example assumes output in lb-ft & horsepower. Dynamometers can also measure torque output in Newton Meters or Kilowatts just as easily, or any other measure of torque and power,...
- 139k
8
votes
Increase my cars BHP?
I'd say the only realistic option with a 1.3 liter turbodiesel besides an engine swap is chiptuning/remapping. And even then I'd research the potential of this engine, you'll be shortening it's life ...
7
votes
Does Max Power RPM Equal Max FE?
The short answer is no. The engine is most efficient at the RPM when maximum torque is achieved. It's easiest to explain with a picture.
Power is a function of torque and RPM. Maximum torque is ...
- 15.9k
7
votes
Accepted
Dynamometer Question - How is it operated and what are they doing?
Generally, in the automotive world, there are two different types of dynamometer (or dyno for short) which might be used: chassis dyno; engine dyno. I'll discuss the general procedures for each type ...
- 139k
7
votes
Accepted
How much horsepower to expect from a cold air intake in Dodge Ram
Would there be a substantial enough of a horsepower boost to be noticeable?
The most you could see from such a modification is 15hp. This would not be enough for the seat dyno to register, unless ...
- 139k
7
votes
Accepted
What is the benefit of Forged Internals in an engine? Pistons, etc
Forging is a process where hot metal of the rough shape is then very forcibly squished by exact shape dies, severely compressing the metal or alloy molecules. There are internal tensions created ...
- 12.2k
6
votes
Accepted
Using an open vs closed clutch cover on a motorcycle with a dry clutch
Reading through some of the Ducati forums has lead me to believe the selection between an open and closed clutch cover on these bikes is mostly for aesthetics. There is some consideration for cooling, ...
- 139k
6
votes
How to increase horsepower?
Engine Remap
One way of increasing the power from your engine, depending on the car is to get your engine "remapped". This effectively means that your cars on-board computer (or ECU) has had its ...
- 7,907
6
votes
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Consequences of a Dirty Intake Manifold
Upstream the throttle body
A dirty intake by itself isn't the problem, but it is a sign of contamination of related components:
MAF sensors don't take kindly to dirt
This will usually lead to the ...
- 38.9k
6
votes
Does an Engine Strut Bar have any effect on performance?
This question and answer from @BobCross is very illuminating and may help you in your decision making process. Have a look.
- 32.7k
6
votes
Accepted
What are the consequences of using an expired tire?
Short answer: Yes, yes and yes. BUT: A tire doesn't have an expiry date.
The reason for all three points is that the rubber gets harder over time and looses its grip / traction, especially on wet ...
- 6,997
5
votes
Does Max Power RPM Equal Max FE?
No, the engine speed at which maximum fuel efficiency is obtained is different.
In fact, the faster you go in any given gear the worse the resultant fuel economy will be because it takes increasingly ...
- 38.9k
5
votes
Accepted
Are there any negative sides to using multiple air filters?
If driving with multiple filters, your vehicle will lose performance. Your car will have a greater restriction in the intake system from having to pass through two separate elements. You would, ...
- 139k
5
votes
Are there any negative sides to using multiple air filters?
If you use more than one air filter, you will make it harder for the engine to suck air into the intake manifold, meaning you will lose power. Less restrictive filters will give you more performance, ...
- 8,805
5
votes
Accepted
Wheel offset effect on performance
Offset is one of a number of measurements applicable to a road wheel and it describes the distance from the centre line of the wheel which the mounting face of the hub is.
As a practical example, lets ...
- 23.3k
Only top scored, non community-wiki answers of a minimum length are eligible