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 ...
cdunn's user avatar
  • 9,326
29 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 ...
J...'s user avatar
  • 692
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 ...
Zaid's user avatar
  • 39.1k
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 ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
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 ...
DucatiKiller's user avatar
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 ...
rpmerf's user avatar
  • 8,443
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 ...
Zaid's user avatar
  • 39.1k
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 ...
rpmerf's user avatar
  • 8,443
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 ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
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 ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
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 ...
Fred Wilson's user avatar
  • 11.6k
8 votes
Accepted

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,...
Pᴀᴜʟsᴛᴇʀ2's user avatar
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 ...
I have no idea what I'm doing's user avatar
8 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 ...
SteveRacer's user avatar
  • 12.4k
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 ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
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 ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
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 ...
Max Goodridge's user avatar
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.
DucatiKiller's user avatar
6 votes
Accepted

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 ...
Zaid's user avatar
  • 39.1k
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 ...
sweber's user avatar
  • 7,047
5 votes

What are Performance Camshafts?

Performance cams have various cam lobe configurations where the valve lift and duration are changed from OEM to provide better efficiency for the combustion process. I would like to make a ...
DucatiKiller's user avatar
5 votes

Increase my cars BHP?

Unfortunately, there isn't a whole lot you can do with a 1.3CDTi - as the others have said, make sure it's in the best condition you can, but you're not going to get the 'kick' you desire. I'm ...
Nick C's user avatar
  • 28.7k
5 votes
Accepted

Remapping a used engine

That's a broad question, and I'm a Subaru geek, not a VAG geek, but I'll share my never-humble opinion. Any flash that increases performance obviously increases stresses. A proper remap with careful ...
SteveRacer's user avatar
  • 12.4k
5 votes

What is gained with "performance" spark plug wires?

Here's an article that explains spark plug cables. It had some interesting information that I hadn't really thought of. That said, I'd say the largest difference in consumer grade spark plug cables ...
kyle_engineer's user avatar
5 votes
Accepted

What is gained with "performance" spark plug wires?

There isn't any performance to be gained from spark plug wires, just better build quality, which gives you not a better spark, but rather maintains an appropriate spark for more miles/years before ...
tlhIngan's user avatar
  • 12.2k
5 votes
Accepted

Most effective weight reduction in modern cars?

Depends on your comfort level. AC system (complete, condensor, compressor, evap, piping, etc), stereo, and every bit of interior except the seats and critical controls. Glovebox, airbags, related ...
SteveRacer's user avatar
  • 12.4k
5 votes
Accepted

Why do most performance cars have longitudinal engines?

It's quite simply because a longitudinally mounted engine equates to less of an engineering challenge to achieve "balance". Imagine something like a large V formation engine, two banks of cylinders, ...
Steve Matthews's user avatar
5 votes
Accepted

Is it more efficient to drive with the windows down or the AC on?

This depends on driving conditions, mainly speed and temperature. AC fuel consumption increases with temperature fuel consumption due to open windows increases with speed The SAE found that AC is ...
Hobbes's user avatar
  • 4,422
4 votes

Does an Engine Strut Bar have any effect on performance?

Tl;dr: it might be better for noise, vibration and harshness than for handling. Once upon a time, I had a Fox body mustang. I remembered it being chock full of rattles and squeaks. It was ...
Bob Cross's user avatar
  • 24.3k
4 votes

Why do modern vehicles omit a temperature gauge?

Your sample may just be non-representative. All the ones I know (I'm mostly into Japanese performance cars) have oil temps. Even many non-performance cars have an indicator that goes out once the ...
Rory Alsop's user avatar
  • 18.6k

Only top scored, non community-wiki answers of a minimum length are eligible