1982 320i m10 engine FI to carburetor conversion

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carlos.otamendi
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My E21(s): 1982 e21 320i

1982 320i m10 engine FI to carburetor conversion

Post by carlos.otamendi »

Hello ,

My vehicle is a 1982 320i M10 fuel injected
Manual transmission swap

I'm looking to convert to Carb side double Webbers, headers, and custom exhaust. Electric fuel pump and regulator

I would like to get all the information can , I have done a lot of searching but not a lot of precise information has been found.

some of the questions I still have:

-What happens to the emissions system, do I still use it? I don't have any emissions in my state.
-Does the fuel sender on the tank gets used?
-What happens to the Kjetronic (dme) does only control injection?
-Do you have to wire the electric pump into the key of the car?
-Do I need to install a choke ?


Wilmo
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Re: 1982 320i m10 engine FI to carburetor conversion

Post by Wilmo »

Hi! I’ll try to answer some of your questions.

You do not need the emission system anymore. Though it will be a best practice to install for instance a wide band lambda sensor with read out in the car so you can see whether the Weber’s are doing a good job under load.

You need the sender in the tank, but not the pump anymore. This is a high pressure pump and you will need a Weber specced low pressure pump for the carbs.

The K-Jet electronics can be removed, you do not have any use of it.

No, you never do that. You need to see the electricity that comes alive after turning the key as a kind of a signal. That signal powers a relay which powers the low pressure pump. The sender in your current car had already a pump, so you have already a relay so you can use that one. You need to integrate your new pump in the old wiring of the relay.

Choke depends on the carbs. I don’t know which ones you intend to use but generally there are three types of chokes. Water, which is automatic, electrical, which is automatic and manual, which isn’t. In case of the last one you need a Bowden cable to the interior to control it.
TaylorGoesFast
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My E21(s): 83 320i, 95 325i Spec 3 Race Car
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Re: 1982 320i m10 engine FI to carburetor conversion

Post by TaylorGoesFast »

What will you do with the head? Plug the holes for the injectors or swap an 02 head?
2011 F150
1995 BMW 325i Spec 3 Race Car
2008 BMW 128i 6 Speed Sport Package
1983 BMW 320i
2005 Kinetic SC
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uwbuurman
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My E21(s): 1978 type 1 323i 5speed dogleg Polaris
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Re: 1982 320i m10 engine FI to carburetor conversion

Post by uwbuurman »

I can provide an e21 4 cilinder carb head if wanted...
It's the man next door!

1978 BMW 323i
1980 BMW 528i maior restitutio
1987 BMW 325iA cabriolet
2006 BMW 320d touring High Executive
2015 BMW 320dA touring xDrive High Executive ///Msport
Wilmo
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Re: 1982 320i m10 engine FI to carburetor conversion

Post by Wilmo »

If I were him, I would source a 318i head.
FlyinE21
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My E21(s): '82 US 320i manual

Re: 1982 320i m10 engine FI to carburetor conversion

Post by FlyinE21 »

I'm doing a similar conversion, so please clarify for me. Does the high volume/low PSI pump replace the inline pump, or the pick up tank pump? If it goes inline is the pick up pump just replaced with a pick up tube then?
LloydRT
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Re: 1982 320i m10 engine FI to carburetor conversion

Post by LloydRT »

Wilmo wrote: Mon Nov 30, 2020 5:05 pm If I were him, I would source a 318i head.
This sounds like a better route for our incoming 320i project.
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