Carb Vs EFI discussion
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Carb Vs EFI discussion Which is better? Which makes more power?
I say EFI is better because you can actually tune for a perfect A/F Ratio across the RPM band so it makes the max power at every point.
Can anybody tell me why or if carbs are better or make more power and how?
I say EFI is better because you can actually tune for a perfect A/F Ratio across the RPM band so it makes the max power at every point.
Can anybody tell me why or if carbs are better or make more power and how?
You can get equal power thru carb and its cheaper but that would only be peak power, EFI will dominate in all other area's.
It would be so cheap for manufacturers to still be producing carby engines but there is a reason why the spend billions of dollars on EFI and continuously upgrading it, world emission standard get stricter byt the year and its harder and harder for manufacturers so they must make the cleanest possibly engines, if they could do it with a carby they would, but they can't.
It would save them hundred of billions of $$ but they simple can not so they need EFI.
But if your into 1/4 mile action, theres nothing wrong with a carby setup as its only 4-7,000rpm, all you need is something dumping fuel in, no need for circuitry and economy stuff.
It would be so cheap for manufacturers to still be producing carby engines but there is a reason why the spend billions of dollars on EFI and continuously upgrading it, world emission standard get stricter byt the year and its harder and harder for manufacturers so they must make the cleanest possibly engines, if they could do it with a carby they would, but they can't.
It would save them hundred of billions of $$ but they simple can not so they need EFI.
But if your into 1/4 mile action, theres nothing wrong with a carby setup as its only 4-7,000rpm, all you need is something dumping fuel in, no need for circuitry and economy stuff.
EFI gives a little more flexibility with street engine combinations, but in most cases a carburetor can equal the performance of EFI.
There's MUCH more money to be made by the manufacturer for service and replacement of EFI parts.
Parts and repairs for carbs would be so cheaply and easily had that manufacturers couldn't even make a small fraction of the money on service after the sell of a vehicle.
There's MUCH more money to be made by the manufacturer for service and replacement of EFI parts.
Parts and repairs for carbs would be so cheaply and easily had that manufacturers couldn't even make a small fraction of the money on service after the sell of a vehicle.
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From: Norn Iron
A carb cannot match an efi system for power spread, torque spread, emissions, economy and general driveability.
They may have the ability to match outright power, but that isnt really important. its the spread of useable power that counts, and a proper efi system will always win.
Assuming carb and efi systems are built within similar constraints. Obviously some economy based efi systems have shortcomings relating to airflow, as would some very small carb+air cleaner assembleys.
They may have the ability to match outright power, but that isnt really important. its the spread of useable power that counts, and a proper efi system will always win.
Assuming carb and efi systems are built within similar constraints. Obviously some economy based efi systems have shortcomings relating to airflow, as would some very small carb+air cleaner assembleys.
I have seen where EFI can hit more hp, and have much better overall driveability but can cost a lot more. I've seen articles that showed a huge increase in part throttle driveability, fuel economy, power curve, and peak hp.
A carb will always make a little more peak power, the mixing of the air and fuel creates a cooling effect which a typical port injected engine doesnt have. OTOH a TBI style setup will be very close to a carb in ultimate power output.
Port fuel injected manifolds can be packaged a lot more efficiently and have long runners (better torque) since fuel puddling/seperation isnt a concern - to a point, air doesnt like to go around corners either.
Anyhow, for emissions, drivabilty, cold starting and tuning ease its hard to beat EFI. A carb is much less complicated (welcome on a race car or old school conversion), can maybe make a bit more power and is much more forgiving to tune, one or two mismatched injectors can drag the output of a whole motor down if you have to tune to the one bad injector. Newer setups can change the individial injector fueling and timing so thats not a huge concern anymore.
Honestly in a n/a drag race only car I'll take a carb for the sheer simplicity (way less wires), but without EFI you wouldnt be driving around cars everyday with the somewhat radical cams and still getting decent milage and pass emission testing.
Port fuel injected manifolds can be packaged a lot more efficiently and have long runners (better torque) since fuel puddling/seperation isnt a concern - to a point, air doesnt like to go around corners either.
Anyhow, for emissions, drivabilty, cold starting and tuning ease its hard to beat EFI. A carb is much less complicated (welcome on a race car or old school conversion), can maybe make a bit more power and is much more forgiving to tune, one or two mismatched injectors can drag the output of a whole motor down if you have to tune to the one bad injector. Newer setups can change the individial injector fueling and timing so thats not a huge concern anymore.
Honestly in a n/a drag race only car I'll take a carb for the sheer simplicity (way less wires), but without EFI you wouldnt be driving around cars everyday with the somewhat radical cams and still getting decent milage and pass emission testing.
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Originally Posted by Bryan TTM
carbs are king...they got that rumble to em...and for those of you who just dont understand em...then run your EFI
id go with carb if i could but because of insepection and such i have to go with efi. but i do trust the carby, reliability wise. for blow through FI systems i would trust efi more though. i guess im split.
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Originally Posted by Bryan TTM
carbs are king...they got that rumble to em...and for those of you who just dont understand em...then run your EFI
EFI or bust.
Originally Posted by stevieturbo
In terms of overall performance, economy, driveability, a carb will NEVER match, or indeed even come close to that of an efi system.
Things must be very different over in Ireland.
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From: Norn Iron
Yes, we have modern cars that are fuel efficient yet still make reasonable amounts of power.
We did used to have old cars with Carburettors, but as times change, and technology improves, we move with the times, onto better things.
That is modern fuel injection. Unless regulations do not permit it, nearly all forms of top motorsport use fuel injection, although motorbike engines seem to be the slowest to take up on that.
The only other's really are dragsters, but then fuel economy and emissions dont even figure into that.
Many modern normally aspirated cars can make over 100bhp/litre yet return good economy, total driveability from idle to redline, in some cases say 9000rpm, even if you wanted to hit WOT in top gear from idle.
How many carburettor cars can match that ?? None.
And as for FI cars....efi works even better.
How many of the 8-900hp cars on this forum, many of which can be driven daily without worry, use a carburettor, seeing as you think they are so good ??
None.
Can some of them return nearly 30mpg...yes. Could a carb car of similar performance match that?? I doubt it.
Or to add...there are some smaller engined cars, such as Evos and Subarus making over 600hp from a relatively small 2000cc, yet they too can be used daily.
Do you think a carburettor version of that same engine could do that ???
No way.
We did used to have old cars with Carburettors, but as times change, and technology improves, we move with the times, onto better things.
That is modern fuel injection. Unless regulations do not permit it, nearly all forms of top motorsport use fuel injection, although motorbike engines seem to be the slowest to take up on that.
The only other's really are dragsters, but then fuel economy and emissions dont even figure into that.
Many modern normally aspirated cars can make over 100bhp/litre yet return good economy, total driveability from idle to redline, in some cases say 9000rpm, even if you wanted to hit WOT in top gear from idle.
How many carburettor cars can match that ?? None.
And as for FI cars....efi works even better.
How many of the 8-900hp cars on this forum, many of which can be driven daily without worry, use a carburettor, seeing as you think they are so good ??
None.
Can some of them return nearly 30mpg...yes. Could a carb car of similar performance match that?? I doubt it.
Or to add...there are some smaller engined cars, such as Evos and Subarus making over 600hp from a relatively small 2000cc, yet they too can be used daily.
Do you think a carburettor version of that same engine could do that ???
No way.
Last edited by stevieturbo; Feb 1, 2005 at 04:14 PM.
Carb will never match EFI for fuel economy and part-throttle driveability.
If a car is all about just drag racing, and there are no class limits, then slap a 1050 dominator on there and go racing.
If a car is all about just drag racing, and there are no class limits, then slap a 1050 dominator on there and go racing.
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Joined: Jan 2005
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From: Pleasanton, CA
From what ive seen, and my expirience is a bit limited. But EFI does make power throught the powerband better. I know this isnt a golden example. But I watched a HP TV and they where switching an older camaro i think it was from carb to EFI. The car gained something like 40-50hp more from beinf switched to fuel injected. And remember the power numbers from the older cars before EFIm wasnt SAE. So I would say EFI. But on the upside for carbs. I have heard(not an expert on this)that when it comes to making immense amounts of power carbs are the only way to go. You can dump an almost endless amount of fuel into those things.
But what about DFI, how much better is that that EFI?
But what about DFI, how much better is that that EFI?
Originally Posted by RaNsOm
Which is better?
Which makes more power?
I say EFI is better because you can actually tune for a perfect A/F Ratio across the RPM band so it makes the max power at every point.
Can anybody tell me why or if carbs are better or make more power and how?
I think it is also pretty well accepted that all other things equal, a carb will make more HP than EFI because the carb does a better job of vaporizing the fuel and a better job of cooling the intake charge because the fuel is introduced at the entry to the intake system rather than at (or near) the valve. This assumes an optimal intake manifold. Ie, it has even distribution, isn't heated by engine oil splash, etc.
If you are having an argument with someone about this, just define "better" to mean a daily driver. Then you win.
I do love the way my EFI car starts. Hot or cold, touch the key and it is running. Not like carbs where you tap the gas pedal to set the choke and maybe have to pump it a time or two, depending on the air temp and engine temp and how long it has been sitting.
Last edited by critter; Feb 1, 2005 at 06:32 PM.
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From: Norn Iron
injectors squirt the fuel in the best place possible ( given design contsraints ).
Fuel does not get washed on the walls of a manifold. You will not get a much better way, other than direct injection, for distributing the fuel than found in most modern injection systems. Having the fuel travel through/around an inlet manifold is not ideal..
You cant compare a maximum power carb/single plane to a stock efi system. Yes the carb may offer peak power , but thats about it.
If you want to compare a performance carb install, then compare it to an LS1 with a max effort multi throttle intake designed for performance. Which will win ?? I wonder.
As a rule, electronic fuel injection is better. It doesnt need broken down, it is just better in every area.
If you are to make comparisons with a stock factory efi, then compare it to a stock factory carb/manifold/air cleaner assembly.
Fuel does not get washed on the walls of a manifold. You will not get a much better way, other than direct injection, for distributing the fuel than found in most modern injection systems. Having the fuel travel through/around an inlet manifold is not ideal..
You cant compare a maximum power carb/single plane to a stock efi system. Yes the carb may offer peak power , but thats about it.
If you want to compare a performance carb install, then compare it to an LS1 with a max effort multi throttle intake designed for performance. Which will win ?? I wonder.
As a rule, electronic fuel injection is better. It doesnt need broken down, it is just better in every area.
If you are to make comparisons with a stock factory efi, then compare it to a stock factory carb/manifold/air cleaner assembly.