Top engine Components for naturally aspirated engines

[Vortex347]

Hi all,

I was just wondering if any of you guys would have a list of top components and materials to include in a performance engine (modifications if you will). Basically if you took an engine (naturally aspirated out of a road car) to a performance engine builder what would he change to get the best out of the engine.
In regards to limitations, I'm not talking about putting a turbocharger on it or anything like that. Basically just keeping the engine as is and swapping out parts.

I'm thinking of things like dry sump system as opposed to a wet sump system, bigger manifold, roller rockers and titanium valves even.

Would you also be able to say why the change is an improvement to the engine over the original component

[flynfrog]

What engine?
What do you plan to use it for?
What car?

This is completely depended on end goals and starting point. If the chassis has a good fuel system ect

[J.A.W.]

Indeed, the technical emphasis would be markedly different for power/longevity modifications to the same engine..
Optimal considerations for a 24hr endurance race build versus a drag race configuration for example..

Some mass production engines are specifically modified - solely for dyno power contests.. see "Engine Masters"...

[Vortex347]

What engine?
What do you plan to use it for?
What car?

Is this really relative?
and no it will not be used for drag race purposes.

Don't think the engine really matters that much or the car. Use hmmm think of it as a normal road going car during the week and a track car on the weekends.

I'm just seeking a list of the top components you can put in an engine to maximize power and torque and the reason why they're better than other parts.

as for the engine, 3.5L v6 out of a toyota aurion, 2.4l 4cylinder out of a toyota camry, 1.8l out of a chevrolet cruze whatever.

I'm not chasing specific part identities. I'm just chasing a list of top engine bits and why they're good.
something like uh.... bigger manifold allows greater air flow and doesn't constrict the engine.

[NL_Fer]

It's not about parts, it's about tuning your engine. Three most effective ways of getting more power is:

1 Pressure charge with a turbo or supercharger
2 Increase displacment with bigger pistons or a new crankshaft
3 Increase rpm, using a different cam, manifold

So what route are you taking? Trully depends of what your project engine is capable off.

[flynfrog]

What engine?
What do you plan to use it for?
What car?

Is this really relative?
and no it will not be used for drag race purposes.

Don't think the engine really matters that much or the car. Use hmmm think of it as a normal road going car during the week and a track car on the weekends.

I'm just seeking a list of the top components you can put in an engine to maximize power and torque and the reason why they're better than other parts.

as for the engine, 3.5L v6 out of a toyota aurion, 2.4l 4cylinder out of a toyota camry, 1.8l out of a chevrolet cruze whatever.

I'm not chasing specific part identities. I'm just chasing a list of top engine bits and why they're good.
something like uh.... bigger manifold allows greater air flow and doesn't constrict the engine.

It all matters. If the stock parts are good enough for the intend power level and use then there is no reason to change them. As NL_fer pointed out its not about parts. An engine is a complicated tuned air pump. Lets take your example of a bigger manifold. I am assuming you mean larger diameter runners to flow more into the engine. So you bolt this on your engine doesn't flow any better because the bottle neck was in the heads but now you have lost port velocity so your intake side is now flowing worse than it was. Also since this was a super high performance race manifold its runners are short tuning the engine for a higher rpm so it wont start making power until long after you are out of the rev range of you cam and other parts.

To piggyback on NL_Fers statment. The fromula for HP is PLAN=HP

P= Pressure in the combustion chamber
L= Length of the crank stroke
A= Area of the piston
N= Number of firing cycles per time.

So think of how the mods you propose will be affecting these parameters.


Ill use the example of the GM Ls series motors. Mostly because I have been building one lately.

Lets pick a power goal of say 400hp. Our engine is out of a junk yard van and makes 300 or so hp. You said no turbos so thats out. I would change to better flowing factory heads change the cam and switch to the car intake to match the heads. It has shorter runners than the truck intake pushing the power into slightly higher rpm, and will fit under the hood a little better. We should now be pretty close to our power goal and around $2k in parts plus another $1000 or so for the engine.


But lets say the factory fuel system isnt up to the task now you need fuel pumps lines filters and fittings. add on another $1000 pretty quickly

[J.A.W.]

& differences in production applications of similar engines used in different vehicles also apply..

The Chev V8 as fitted to a Corvette is differently configured to a truck mill, & will likely be lighter & lower too..

& the ostensibly similar Toyota units will differ between basic auto econo-box FWD Camry & sporty RWD Supra/Lexus types..

[Cold Fussion]

The OP's question is so vague that it has no meaning at all. Without any context it's impossible to have any logical discussion. If I had two rotax max engines which I gave to two different engine builders, one I told it needs to make 50 hp, the other I told it needs to power a spitfire, the list of changes they would each recommend will be completely different. Without requirements it is impossible to achieve anything.

[flynfrog]

[youtube]www.youtube.com/watch?v=6bkDKqoGSdU[/youtube]

Here is a pretty good video by Steve Dianan. Its mostly focused on ECU tuning but gets lightly into general engine upgrades as well.

[mzivtins]

I would uprate all valve train components, go titanium where possible, stems and sleeves.

Go magnesium for the heads for reduced weight.

Pneumatic valves.

Light-weight high comp pistons

full titanium exhaust manifold.

adjustable velocity stacks on intake ports, programmed to actually work

The biggest improvement would come from completely new ignition systems, race spec coil packs and full Mil-spec wiring.

Low mass flywheel, stage III clutch (or even more extreme, but you'll struggle ever reversing up a hill )

All i can say is.. look at any litre superbike on the road in the last 10 years, see what they use and apply it to the NA engine ideas it is a great place to start