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Posted by: Luke M Nov 29 2012, 11:57 AM

My brother has a 74 914 2.0 that's going to get a 83 3.0 SC installed into it.
The engine is going to be run with Weber carbs. I know that some members may have a 3.0 installed in their 914's . The question that I have is what type of ignition source are you using?
I've heard the 83 distributor cant be used and need to use an earlier one ?
Can a MSD 6AL box, & coil be used instead of the cd box?
The engine wire harness what's needed to make this work?
Any help would be greatly appreciated.

Thanks,

Luke

Posted by: Mark Henry Nov 29 2012, 01:33 PM

Don't know why a '83 dizzy couldn't be used
I know SC dizzys run backwards (CCW), so you can't use an earlier or later dizzy in a SC.
Pretty sure you can use the MSD 6AL.

Ask over at the bird board engine rebuild forum, they will know for sure.

Posted by: Luke M Nov 29 2012, 01:41 PM

I was planning on hitting up the guys on the Bird board later today.

The p/o told me I couldn't use the distr because there's no mech advance and to use an early 3.0 unit.

I'll do some research hopefully come up with an answer.

Thanks

Posted by: Mark Henry Nov 29 2012, 01:54 PM

No mechanical advance? My 79 has both, for webers you would get rid of the vacuum advance and recurve.

There is the MSD AL6-2 programmable, you lock out the dizzy and program the curve via computer. USB update so you don't need a laptop. They have had problems with the small cap 2.0-2.7 dizzy's phasing but a 3.0 cap and rotor are larger so maybe it would be OK.

Posted by: tommott77 Nov 29 2012, 01:58 PM

I'm relatively certain that the later dizzys don't have enough total advance to properly run on a carbed motor. My carbed 2.5L 6 runs around 35 degrees total advance and I want to say that those later SC dizzys max out at 20 something degrees BTDC.

A MSD and coil will work.

Posted by: Jeffs9146 Nov 29 2012, 02:04 PM

Mine is fi so it would be different!

Posted by: Mark Henry Nov 29 2012, 02:04 PM

Another option is a Megajolt jr EDIS ignition or you can run megasqirt in ignition only (many options including a locked out dizzy/MSD).
Both would give you programmable crankfire ignition.

Posted by: Jeffs9146 Nov 29 2012, 02:13 PM

Double post!

Posted by: rfuerst911sc Nov 29 2012, 06:36 PM

I have a 1978 3.0 big port in the 914 with Weber carb's and a 1983 911 SC with small port and PMO carb's and for both I'm using the OEM ignition distributor. However both were rebuilt/recurved to be used for carb's and both work great. Barry Hershon did one and Jerry Woods did the other. Each one was $600.00 .

Posted by: Krieger Nov 29 2012, 09:15 PM

I have a carbed 78 3.0 with an assortment of parts and senders so I made my own engine harness. MSD 6A. I also eliminated the relay board. Jerry woods for for the recurved distibutor $575

Posted by: sixnotfour Nov 29 2012, 09:42 PM

Call Shea he has a better guy.. west coast


A 3.0 euro distributor works good with carbs.

Posted by: ConeDodger Nov 29 2012, 09:52 PM

I just saw a friends car with EDIS and Megajolt. It cured his idle problems, allowed him to program in a very quick advance. I was very impressed. I will be going this way with my 240Z.

Posted by: moparrob Nov 29 2012, 10:01 PM

+1 for the Jerry Woods solution. Call him - he is VERY helpful and his work is top notch.

Your next stop should be Perry Kiehl for a new engine harness. He custom made mine for my 3.0 running a MSD 6-AL box, and in my case I had him delete my relay board.

Call these guys as they are the best in the business. You will leave a wiser man.

Posted by: Mike D. Nov 29 2012, 10:15 PM

I'm running a webber carb 3.0 with stock dizzy. I split the "pigtail" wire from the dist. and plugged it right in to a MSD6al with no problems. I made my engine harness from the old 911 harness (eliminated most of it) and plugged into the relay board. I guess I thought it would be easier that way.

Posted by: Van914 Nov 30 2012, 05:43 AM

rfuerst911sc Nov 29 2012, 07:36 PM
Post #9


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I have a 1978 3.0 big port in the 914 with Weber carb's and a 1983 911 SC with small port and PMO carb's and for both I'm using the OEM ignition distributor. However both were rebuilt/recurved to be used for carb's and both work great. Barry Hershon did one and Jerry Woods did the other. Each one was $600.00 .


Exactly what I did with mine. Barry did mine. Ran great!!!!!
Van914

Posted by: Luke M Nov 30 2012, 09:30 AM

Thanks for the input guys.
I checked out the Bruce Anderson book and this is what I found.
80 and later 3.0 SC engines will require the distributor to be recurved.
Bruce also states that you can use a 78-79 3.0 SC unit with carbs or a European distributor. I plan on calling either Jerry Woods or Eric's guy at some point today.
Hopefully I'll have a concrete answer from one of these experts.
Does anyone have a wire schematic that they may have made up while doing their 3.0 install ? wiring for the MSD box? The other question is which MSD box model to use with this engine?

I have an email into Perry on a wire harness for this engine. I'll have to wait and see what he recommends.

Seeing how there's a 90 day warranty with this engine I'd like to get it up and running ASAP. The p/o stated that this engine was a 60000 + mile engine that ran strong just removed for a 3.6 conv.

Thanks,

Luke