Weber vs Fuel Injection Options

[anthony]

Using race cars as examples of 'how carbs are good' doesn't prove much to me. Other than a brief moment at the start of the race, a race car will live in it's upper rpm range the whole duration of the race. It's probably pretty easy to tune a carb for the engine's high rpm range at WOT.

A pure AX car would probably get much more adantage than a track car by using EFI. The best setup would be EFI with crank fired ignition. That way ignition advance can be maximized at every rpm and the engine could have the best possible torque curve.

But most people build AX cars on a budget and putting several grand into crankfire EFI and the nece$$ary tuning is beyond most budgets. And that doesn't take into account how many points you'll get for EFI or which class it might push you into.

[Mark Henry]

I laugh at these posts, everyone says that what they have is the best, even if they have never used anything else.

We are the Weber, all others are irrelevant, you will be assimilated, you must comply (IMG:style_emoticons/default/assimilate.gif) (IMG:style_emoticons/default/assimilate.gif) (IMG:style_emoticons/default/assimilate.gif) (IMG:style_emoticons/default/assimilate.gif) (IMG:style_emoticons/default/assimilate.gif)

[Bleyseng]

Using race cars as examples of 'how carbs are good' doesn't prove much to me. Other than a brief moment at the start of the race, a race car will live in it's upper rpm range the whole duration of the race. It's probably pretty easy to tune a carb for the engine's high rpm range at WOT.

A pure AX car would probably get much more adantage than a track car by using EFI. The best setup would be EFI with crank fired ignition. That way ignition advance can be maximized at every rpm and the engine could have the best possible torque curve.

But most people build AX cars on a budget and putting several grand into crankfire EFI and the nece$$ary tuning is beyond most budgets. And that doesn't take into account how many points you'll get for EFI or which class it might push you into.

On a AX car torque is good as coming off a corner and accelerating to the next is where its at. Now the poster was talking about

"I just bought a 1976 914 and am thinking about replacing the
FI with carbs. Is this a mistake?"

Now this isn't a six nor a race car but a stock 4 so I think FI is the ticket UNLESS he changes the cam. I don't think he will be driving around at WOT like Miles. (IMG:style_emoticons/default/yawn.gif)

[dhopkins]

Here is my problem. At the low end when I step on the gas pedal the car does not accelerate smoothly. I press the pedal a little and nothing much happens. I press it a little more and still very little happens. I press it so more and it takes off with a jerk. Its like either on or off. Making a smooth take-off is very difficult. Is this a characteristic of the FI? My other 2 Porsches ('81 911SC and '69 911S)have carbs (Weber and PMO) they don't do this. What is the cause?

Don from Philly (IMG:style_emoticons/default/dead horse.gif)

[Carlitos Way]

Here is my problem. At the low end when I step on the gas pedal the car does not accelerate smoothly. I press the pedal a little and nothing much happens. I press it a little more and still very little happens. I press it so more and it takes off with a jerk. Its like either on or off. Making a smooth take-off is very difficult. Is this a characteristic of the FI? My other 2 Porsches ('81 911SC and '69 911S)have carbs (Weber and PMO) they don't do this. What is the cause?

Don from Philly (IMG:style_emoticons/default/dead horse.gif)

I would venture to say throttle position sensor needs to be cleaned/replaced from what you're saying.

[dhopkins]

Who sells these?

[SGB]

I have Weber 40s, with corresponding cam & dizzy & exhaust changes. Usually my car runs great. But until yesterday when I pulled 'em, disassembled, cleaned and blew out, etc, I had somewhat reduced performance from crap in the passeges- again.
BUT
At the SEC, I ran along behing Jason (D1A4 I think is his club name), with a completely stock 2 liter. His car was so SMOO-OOTH sounding, and my "hot rod" engine had to work really hard to keep up.
Summary-
I wish I had the FI. My carbs have been pretty reliable, but just not as balanced as FI, and never will be. And carbs can be frustrating too as Brad Anders experienced. I think it would be worth it to go through the FI system, make everything righty-tighty, and think pure thoughts from now on.

[Bleyseng]

Here is my problem. At the low end when I step on the gas pedal the car does not accelerate smoothly. I press the pedal a little and nothing much happens. I press it a little more and still very little happens. I press it so more and it takes off with a jerk. Its like either on or off. Making a smooth take-off is very difficult. Is this a characteristic of the FI? My other 2 Porsches ('81 911SC and '69 911S)have carbs (Weber and PMO) they don't do this. What is the cause?

Don from Philly (IMG:style_emoticons/default/dead horse.gif)

Can be a bunch of issues:

check the advance plate for sticking in the dizzy
check the MPS for proper #'s and is it rebuild by AA?(a incorrect rebuilt MPS works like your symptoms)
check for vacuum leaks
check for a sticking throttle plate inside the TB
etc....