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> Double Relay After Carb Conversion, Is there any use for the Double Relay After Carb Conversion?
downrange
post Aug 23 2019, 10:51 AM
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I am converting L Jetronic fuel Injection to single carb with electric choke. Is there any use for the double relay?
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SirAndy
post Aug 23 2019, 11:18 AM
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Noooooooooo

That's for both, the "conversion" and the dual relay ...
(IMG:style_emoticons/default/biggrin.gif)

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jcd914
post Aug 23 2019, 12:38 PM
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L-jet is a good FI system in general and is usually fairly easily fixed.

A single carb on ANY flat engine is a bad idea.
With the flat unheated intake runners on the type 4, fuel tends to fall out of suspension and collect on the bottom of the intake runners. This usually means lean mixture and poor throttle response.
Often the mixture is set overly rich to compensate and which only masks the issue.

If I was on a budget and could not fix the FI, I would opt for dual single throat 34 mm carb kit long before any single carb kit.
Jim
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Tdskip
post Aug 23 2019, 12:51 PM
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Don’t do it without a REALLY good reason.

Why are you considering this?
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rhodyguy
post Aug 23 2019, 02:23 PM
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If you go the carb route, plan on a new low pressure fuel pump and all that goes with that. Carbing your engine brings a new set of challenges.
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porschetub
post Aug 23 2019, 03:00 PM
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Real backwards step in terms of efficiency and reliability,without pre-heat this kit is a waste of money,I often wonder if the plenum ices up in cold climates like the T1 will do with a blocked heat riser ?.
Perhaps the OP could mention what is wrong with his L-jet,many folks on here could assist with answers,its not a complicated system.
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dr914@autoatlanta.com
post Aug 23 2019, 03:32 PM
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don't do it! You will be very unhappy. The L fuel injection system is the best one that the 914 ever had


QUOTE(downrange @ Aug 23 2019, 09:51 AM) *

I am converting L Jetronic fuel Injection to single carb with electric choke. Is there any use for the double relay?
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downrange
post Aug 23 2019, 08:30 PM
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The carb conversion is underway. A simple answer to a simple question would be nice. The comment that the L Jetronic fix is easy does not help.

P.S. I can reinstall the L Jetronic system if I do not like the results from the carb conversion. Getting the car on the road is all I am trying to do.
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JeffBowlsby
post Aug 23 2019, 09:10 PM
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Several skilled and experienced 914 owners have spoken here, not in an effort to be critical but recognize that in this community, many are willing to give you the benefit of their wisdom from lessons learned (mistakes made) by those who have done what you are intending to do now. Please do not take their recommendations lightly. What you have not mentioned is the purpose and expectations you hope to achieve from the single carb, but you don't need ours or anyone's approval.

That said, the L-Jet ignition harness will need significant modification to use with carbs, basically a full rebuild and reconfiguration. A D-Jet ignition harness is the plug N play solution for carbs.
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porschetub
post Aug 24 2019, 01:17 AM
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QUOTE(JeffBowlsby @ Aug 24 2019, 03:10 PM) *

Several skilled and experienced 914 owners have spoken here, not in an effort to be critical but recognize that in this community, many are willing to give you the benefit of their wisdom from lessons learned (mistakes made) by those who have done what you are intending to do now. Please do not take their recommendations lightly. What you have not mentioned is the purpose and expectations you hope to achieve from the single carb, but you don't need ours or anyone's approval.

That said, the L-Jet ignition harness will need significant modification to use with carbs, basically a full rebuild and reconfiguration. A D-Jet ignition harness is the plug N play solution for carbs.


(IMG:style_emoticons/default/agree.gif) very much sums it up,and well said Jeff,appears he shouldn't have even asked about anything really.
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GregAmy
post Aug 24 2019, 07:00 AM
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lol...poor guy...

QUOTE(downrange @ Aug 23 2019, 10:30 PM) *
A simple answer to a simple question would be nice.

Sime answer is "no. You're going to be completely rewiring the engine compartment to install carb(s). Cut out all the wiring (or wrap it into a little ball and tie-wrap it to the side), remove the double relay, remove the relay plate, and start from scratch on engine compartment wiring. Alternatively, you could keep the relay plate to manage the pump and blower motor."

You'll basically need power to the coil and the yellow wire to the starter. How you decide to mount and manage the replacement fuel pump is at your discretion. You'll want to get access to a factory wiring diagram to understand what all that is doing for you.

<-- owns both a D-jet street car and a dual-Dellorto race car...
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dr914@autoatlanta.com
post Aug 24 2019, 09:01 AM
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Sime answer is "no. You're going to be completely rewiring the engine compartment to install carb(s). Cut out all the wiring (or wrap it into a little ball and tie-wrap it to the side), remove the double relay, remove the relay plate, and start from scratch on engine compartment wiring. Alternatively, you could keep the relay plate to manage the pump and blower motor."


OUCH OUCH OUCH
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Rand
post Aug 24 2019, 09:07 AM
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Wow. Just buy a cheap Civic until you can do a 914 right. The 914 is not the best choice for you right now.
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dr914@autoatlanta.com
post Aug 24 2019, 10:28 AM
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Amen brother


QUOTE(Rand @ Aug 24 2019, 08:07 AM) *

Wow. Just buy a cheap Civic until you can do a 914 right. The 914 is not the best choice for you right now.
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downrange
post Aug 25 2019, 08:09 PM
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QUOTE(GregAmy @ Aug 24 2019, 07:00 AM) *

lol...poor guy...

QUOTE(downrange @ Aug 23 2019, 10:30 PM) *
A simple answer to a simple question would be nice.

Sime answer is "no. You're going to be completely rewiring the engine compartment to install carb(s). Cut out all the wiring (or wrap it into a little ball and tie-wrap it to the side), remove the double relay, remove the relay plate, and start from scratch on engine compartment wiring. Alternatively, you could keep the relay plate to manage the pump and blower motor."

You'll basically need power to the coil and the yellow wire to the starter. How you decide to mount and manage the replacement fuel pump is at your discretion. You'll want to get access to a factory wiring diagram to understand what all that is doing for you.

<-- owns both a D-jet street car and a dual-Dellorto race car...


Thank you.
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downrange
post Aug 25 2019, 08:14 PM
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QUOTE(Rand @ Aug 24 2019, 09:07 AM) *

Wow. Just buy a cheap Civic until you can do a 914 right. The 914 is not the best choice for you right now.


I hope you were smiling when you sent this.
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HansJan
post Aug 25 2019, 08:21 PM
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I run dual carbs.
I hate everything about it.
It never runs great.

I wish Fuel injection was a viable option for my car.
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