Airpak

im stupid.
are there any benefits of a carburated engine?
is a fuel injected one better?
i don't really know anything, so whats the difference.

RB83L69

It's typically much easier and far cheaper to get more power out of a carb compared to FI; subject of course to the rest of the engine, and the purpose at hand.

FI typically gets a little better gas mileage and potentially alot lower emissions than a carb; but is much more difficult to tune to an engine set up for racing.

If you already have a car set up for the one, IMHO it's best to use it, rather than trying to hack the other in. Unless you have a whole donor car to get all the little detail things that are different; starting with the gas tank and fuel lines.

ShiftyCapone

iTrader: (7)

A carb is a mechanical devise that lets an amount of fuel in for a certian amount air. Basic physics and thermodynamics makes it happen. The inlet air flows through a venturi nozzle and atomizes the fuel based on the difference of air and fuel speed entering into the manifold. Depending on the engine speed and throttle position fuel is meterd based on air flow.

The are many types of FI (fuel injection). Some are similar to carb (TBI) and others implement direct injection of fuel into either the port of the intake manifold runer (port injection like TPI,LT1, LS1) or into the cylinder head (direct cylinder head injection found on some newer nessans). A computer determins the amount of fuel required based on throttle position, engine load, AF ratio, and engine speed. The computer gets this data through a series of sensors that provide feed back to the computer.

Carb is a more simplistic system that can support large power numbers. However, it cannot touch the fuel managemnt, and emissions reduction capabilites that a FI system can meet because it is stickly a non-feedback system (it can't make corrections). Todays FI is far superior to most carb set-ups out there. It comes at an expense though. FI gives you the ability to change a whole slew of parameters throughout the powerband to support all kinds of engine combos. That is why you can have a 346ci LS1 making 500 at the crank while still holding a smooth idle and getting 20+ mpg. You won't see that with a carb.

Hope this helps a little.

Airpak

yeah i get like 13 mpg with my 350 =P
i dont really mind though. so what kind of advantages or things can i do to pump out the most power with my carbed engine?
its street driven, but not daily, its more occasional.. it probably wont be a track car either, since we have no track here =P n the closest one if probably a few hundred kms away.

ME Leigh

Thats not why, but i know what you mean.

ShiftyCapone

iTrader: (7)

I didn't want to go into the nitty griddy with cam design/profiles and such that allow for it Glad you catch my drift.

Airpak

what would be the most important performance enhancers for a carbed 350?
i should have a few grand (canadian) left this summer, and i'd like to do things myself, but right now i dont know much. i should probably find a dyno though, because im sure im pumping out quite a few horses right now.

ShiftyCapone

iTrader: (7)

Start with a full exhaust from the motor to the tail pipe and then look at a heads and cam swap. You may be able to make something out of the heads you have now pending they are not old smoggers.

Lonestar

In what way does thermodynamics have anything to due with a carb...unless you have a problem with vapor lock?

five7kid

iTrader: (14)

Phase change of the fuel, fuel/air mixing, etc.

ShiftyCapone

iTrader: (7)

Yup. An engine is a mass in mass out system.