Worm up with EFI

[forestb]

Do the aftermarket EFIs that replace the carborator help with having to worm it up?

[dougf]

No, the engine will warm up based on other variables such as displacement, idle speed, cooling system to include radiator size, thermostat, electric vs belt driven fan, and ambient air temperature.

EDIT: if you mean driveability then yes, the EFI should adjust based on the above variables to help it idle better and drive better during any temperature, however the actual warming of the engine should be unaffected.

[forestb]

Does that mean I don't have to sit and wate for it to worm up before driving?

Originally Posted by dougf

No, the engine will warm up based on other variables such as displacement, idle speed, cooling system to include radiator size, thermostat, electric vs belt driven fan, and ambient air temperature.

EDIT: if you mean driveability then yes, the EFI should adjust based on the above variables to help it idle better and drive better during any temperature, however the actual warming of the engine should be unaffected.

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[BOE]

my efi only replaces the distributor

[gar187er]

a full EFI setup with have a computer/ timing adjustments, A/f ratios, etc...

so yes that would eliminate the need to have the engine warm up.

But some systems arent a full EFI setup with all the sensors.

[PGSigns]

Your think of your HEI not EFI. EFI can make it run much better cold. It can richen the mixture and keep the idle where its needed much better than a carb.
Jimmy

[donthekawguy]

Warm.

[The Rocknrod]

Originally Posted by donthekawguy

Warm.

Maybe he wants to worm up the driveway.

[jchav62]

Originally Posted by donthekawguy

Warm.

!!!

I wanted to reply the same...

[forestb]

Grrrrrrr

Originally Posted by jchav62

!!!

I wanted to reply the same...

[Chevy Fleetside]

I have a carb and drive it cold. Just don't lay into it and drive it slow. I would like an EFI just for fuel mileage but I doubt the cost would be worth it.

[patrickk1]

I would think that regardless of EFI or Carb, you would need to warm up the engine the same. 5-10 minute warm-ups are unnecessary. It is better to warm up the car for a minute and then drive lighty for the first few minutes to warm up your engine. This also warms up your engine faster. Most EFI systems don't even run in closed loop mode until the engine is up to operating temperature anyways, so there is no input from the 02 sensors to adjust the airfuel ratio. It is just running using predetermined maps.

[joedoh]

Originally Posted by patrickk1

I would think that regardless of EFI or Carb, you would need to warm up the engine the same. 5-10 minute warm-ups are unnecessary. It is better to warm up the car for a minute and then drive lighty for the first few minutes to warm up your engine. This also warms up your engine faster. Most EFI systems don't even run in closed loop mode until the engine is up to operating temperature anyways, so there is no input from the 02 sensors to adjust the airfuel ratio. It is just running using predetermined maps.

a carb has one idle jet size. to warm up a carb engine you set the choke (with a cable or by pressing the gas pedal down and engaging the automatic choke system). a "choke" limits the amount of air going into the engine so that the system runs rich. You manually manipulate the choke cable as the engine warms up, or the automatic choke uses an electric bimetal strip or a water temp waxstat to open the choke. all of these, especially the electric choke, can open the choke before the engine is warmed up and cause poor running.

EFI uses a fuel map to correspond to the rpm, incoming air temp, air volume (or manifold air pressure), and water temp, and injects a precise amount of fuel for the engine. there is no choke butterfly in most EFI systems (some still have them, I bought a $200 RX7 turbo that had a stuck choke butterfly). Sometimes there is an idle air control valve that allows air past the throttle blades. there is no idle jet equivalent, the amount of fuel injected is the perfect amount to keep the engine running.

its really about idle on warmup, although a cold engine with a carb also only has one main jet size too, so opening the throttle on a carb engine when it isnt sufficiently warm can make it stumble, sputter, or stall because the main jet size does not know it is 20 degrees or 80 degrees.

I have had a lot of carb vehicles, and I either had the cold/choke idle set high so it would rev 1500-1800 rpm until the choke opened or worse, I sat in the car/truck feathering the throttle to keep it going. I have had a lot of EFI vehicles, and all but the oldest system was able to drive away smoothly after less than a minute.

[LostMy65]

Do to joedoh posts the last few weeks, plus what I've been reading in the Engine & Drivetrain forum, I went ahead and ordered a new Fitech EFI.
They have a new one out that's only $795.

[jb9281]

what is the part number for that efi system and who has it for that price?

[LostMy65]

Originally Posted by jb9281

what is the part number for that efi system and who has it for that price?

http://Www.67-72chevytrucks.com/vboa...d.php?t=686601