What are the most common bottlenecks that make engines put out much less power than neccesary...

What are the most common bottlenecks that make engines put out much less power than neccesary? I could start modding the shit out of an engine but that won't do much if there are restrictions in the intake/exhaust system.

intake (manifold, throttle body,air box (CAI))
exhaust(headers,catalytic converters, exhaust size)
injectors
fuel pump
mass air flow size
Stock tune is usually for 87 octane fuel

Older cars really benefit from that, newer cars are more hit or miss since most parts are well designed for the car, not to drop the power so it gets some efficiency pass

By necessary, do you mean "potentially"?

>all emission equipment
>injection system
>turbo pressure
Remove the first, modify the other two. Note; doing this improperly will kill your engine

Does the length of the intake negatively affect anything, like throttle response? If I were to ever modify the intake I would make a proper CAI which involves routing the intake as close to the outside as possible. I guess the benefit of having a cold air feed would outweigh the possible drawback of a mile long intake, right?

Added +50 hp to muh subaru

Added a decent amount to my speed 3. Also have an AP3 with purple drank tune 93 tune. Have a boost intercooler tube that I got for free that I'm gonna add when it stops raining, next is the more expensive things and fucking with the turbo/exhaust. Can't decide to do sway bars and tires before that or after, cause gonna have to save for a bit. Also this stuff was really easy to install.

Congrats on your 51 hp Subaru.

Good stuff.

It has at least 300 per drive wheel after this sicc mawd

>boost intercooler tube
wat

Go full catless and 3" from the turbo back

I just painted all my caps red. What are my gainz?

Idk, I got handed it and Googled it to see wtf it was, I know where it goes and what it does, just not what it's exactly called I guess. I was thinking catless turbo back cause it should be cheaper catless and I don't get emissions tested really where I live. I need to just send in a run to a tuner and say that I don't have cats and they'll send a map back for catless right?

Oh look it rotated my picture. Does that mean my turbo was rotated too?

I'm actually unsure on the speed 3. The subaru's ots cobb maps are the same for catted/catless

It means your engine is rotated. Congrats on the longitudinal mount simply by tilting your head.

Anything that hinders the flow of air into the cylinders. That includes tha camshaft profile.
A cam and head swap can double output easily. Streetability may suffer. Ymmv.

>Does the length of the intake negatively affect anything, like throttle response?

Yes. Shorter intakes will give better throttle response and more top end power. Longer intakes will improve low and mid range torque and horsepower. A properly designed intake with a supporting tune will likely increase power in all areas over stock

One of the common problem with stock intakes are the baffles. The accordion like shape is designed to quiet airflow but creates air resistance and little pockets of turbulence that slow the air. Some cars even have a "muffler" which is basically a separate chamber attached to the intake to again reduce noise.

if they have a r o t o r

No one has mentioned it yet, but on older engines:

-Cam timing is retarded from the factory to run lower-octane fuel.

how old is older

different cars are different

Pistons/rods
Clutch
Most stock give out 40-80 ft/lbs over stock
Assuming you plan on making actual power, not muh 300hp cobb stage 5227622 vapemachine, a decent set of forged & balanced internals with the right size turbo/supercharger, a grand or so into fuel, another few in tranny/tuning mods you'll have a real high hp. Without dropping the compression too low and keeping your stock top end, you'll keep the reliability and drivability of your stock car (so so assuming you don't have a 4 puck+dogbox).

On the other hand, if you only have a few grand, pick up a cheap civic/integra and turbo it. With a proper tune you'll be able to hit at least 200hp in a car that weighs barely over a ton.

Whatever you do, don't fuck with your daily unless you have the dosh to get quality parts and every supporting mod that comes with it. Take this from first hand experience being a dumbass teen.

What year and engine?
Exhaust foremost. Intake is negligible unless you run without a filter. Camshaft duration and valve lift is small on modern engines so they can put out more torque (because they're fucking small). Almost any engine pre1996 was limited by exhaust port flow. Engines before 1986 had retarded camshaft and low compression. Modern engines are now limited by shit displacement

post 1973

Really depends on the car. I have a wrx for example and the stock stuff can handle a lot more HP than it is stock.
>so wait lol why wouldn't they just give it more HP then lol Subarufag?
Emission restrictions are probably one of the biggest factors, look up and see how other people tune your car before you start bolting on intakes or new exhaust systems.