Throttle response: Carb versus multi point EFI

[eco]

I have been noticing that carb'd motors seem to have much better throttle response that does EFI. I never really paid much attention to it before. My Duster (carb'd) will rev to 5000RPM as quick as you can open and close the throttle plates. If I do the same thing to my two EFI motors there will be a little bit of a delayed reaction then the RPMs will shoot up a little bit, but not much. In order to get up to 5000RPM with the EFI motors, I would have to hold the throttle open for little bit as opposed to snapping it open and shut as fast as I can.

Anyone else noticed this?

Anyone know exactly why this is?

 

[surewhynot]

I have noticed that also. Just guessing, maybe it takes a little for all the sensors to communicate with the computer to figure out what to do.

 

[F 150Cobra]

doesnt it depends on the engine??

more Hp quicker response?
and also the
Shorter stroke 302 winds up allot! quicker than the 351..

 

[surewhynot]

I have even noticed the same thing on stock efi 302 vs. stock carbed 302.

 

[john112deere]

My uncle had a mid-'90s Subaru (EFI with mechanical throttle linkage, manual trans), and he removed something from the throttle linkage to make it close faster. He got a newer Subaru, and when he tried to do the same thing, found out that it's got an electronic throttle, and he couldn't.

I know this isn't the same thing you're talking about, but what he told me (he's an old-school hot-rodder and engineer, so he usually knows what he's talking about) was that Subaru had added this thing to keep it from backfiring when you let off the throttle.

My point being that it may be on purpose, either to make it run more smoothly, or to prevent you from damaging anything...

 

[d-kuzmen]

When you step on a carb'd engine the carb dumps fuel into the engine directly, if you do the same to an EFI It see's the TP change then has to do it's math and adjust the amount of fuel needed, so yes there is a difference, the fly by wire even has more of a delay to it. If theres a rev limiter in the pcm that will hold it back also, the newer cars are also alot smarter, it may rev up faster when in gear then in neutral, there programed to not allow you to blow it up on purpose, so if it see's you doing stuff that may damage the engine or trans it'll back off alittle, try doing a neutral drop with a car that has a CVT tranny in it. Won't do it, won't engage the trans untill it drops the rpms down to a safe level.