OK. I hate things that are unresolved and this certainly seems to be (at least) the main issue that needs to be addressed.

I think a 123 should be in my future and I'll add the decel valve while I'm at it.

Thank you for the vacuum info - there's a lot out there and this is a very helpful slice.

Yes, good advice. I bet you might find a decel around here. Any conversion means no use for it. Although I would add, your motor does not, and never had, a vacuum advance. You can see the port is sealed on your TB.

The 123 is a great addition. No damage done, you can put the original dizzy on a shelf for the next person if they want it original.

In the meantime, just plug the TB port for the retard and disconnect it. It isn't doing anything anyway. It's a vacuum leak and that is all.

Ok....to the OP, while the port might not be there if it's a 74 TB doesn't mean you shouldn't have it. I'd recommend a TB if interested for fun's sake and driveability sake.

Just becuase in 74 it was a change was made...doesn't mean it was better. While you
you are sourcing the Decel valve I'd recommend a TB with ported vaccum for a 2.0.

The last copy and Distributor post from Brand Anders site:

As the model years of the 914 progressed, emission restrictions became more stringent. Later cars (75-76) had additional systems added to combat emissions, such as an air pump and exhaust gas recirculation (EGR). But one other change was made that is not noticed by many owners, which is that on the later cars, the vacuum advance port from the throttle body was attached to a hose that was capped off, and not connected to the vacuum advance cell of the distributor. Why? Because while vacuum advance improved engine throttle response under part-load conditions, it also increased HC and NOx emissions, limiting the ability to meet emissions requirements. Furthermore, since there was no change in the vaccum cell unit used on these later cars, the vacuum retard remained active long after the throttle was opened, because no vacuum was ever present in the advance cell. This had the additional effect of causing even worse off-idle response.



It is clear from this discussion that this is a complex system and that for proper operation, all components must be functioning properly. Below is a list of items that should be checked to make sure that the advance systems are working properly.

Yes, I was an advance supporter too for exactly those reasons (the cool balancing act between the two parts of the can particularly) but after a/b ing the driveability using a 123 with advance, without, with retard, without, I have found the digital distributor doesn't need advance (as many others have found as well). I will keep trying it (all I have to do is put the hose back on) to see how it affects the 2056 with much higher compression, but I am not expecting much. I have found zero difference with part throttle tip in etc. I rarely stick my neck out like this, but with a 123, advance just isn't necessary. The same company that brought you the crazy retard advance dizzy also decided it wasn't necessary in 74. Did it help a 74 if you switched to a 73 TB with advance? Not sure. I haven't seen anyone add it or talk about adding it to a 74-76. Advance on the 2.0 was a 1 year thing.

OK - how do I determine which decel part number is the one for me: 039133551?
I think I'll need a stacked elbow as well and the proper additional hoses.

Do I need to be the ringleader for another 123 group buy?!

(and a serious thank-you to everyone offering up the input and advice - I know it takes time to read in and then formulate a response - I appreciate it!)

You shouldn't need a t for a late 74 I believe. Your plenum looks like it is for a passive PCV system. That is where the pcv goes into the air box and there is no valve on the oil filler box. The small plugged nozel goes to the decel, and the big nozel next to it goes there as well. The third port on the decel goes to the air box. I wish Jeff would chime in though. In his diagram for late 74 it has an active pcv with valve and the t. The t needs a big port on the plenum
Click to view attachment

Here is mine, but it's a 73. Probably the same.

Click to view attachment

0280160108

227 below that number

Thanks for this - there are two different model numbers on ebay (0280160108 and 0280160124 for example) at the moment - I'll do some research but may also start a new thread on decel valves....

Soo.... some very interesting things in my 2056 build related to this. Basic background. Stock 2.0, 96mm pistons, flat tops, new sleaves, cleaned up the heads and new guides. Didn't crack the case. Cleaned all the crap off the engine. 8.4:1 compression ratio. Didn't touch the dizzy or any settings on the fuel injection.

My car used to run pretty cool. As described earlier.

the 2056 Ran really warm, just as Brian described for his 2.0 in fact.

I put the advance hose back on (123dizzy) and ch temperatures at cruise fell considerably. 20 degrees I estimate. Put about 4 degrees advance into it and performance suffer and temps were no different. Pulled it back about 2 degrees and performance peaked and the temp was more consistently low during hard acceleration. Still higher than before but my bad rings and leaking valve guides were not making for a fine tuned engine. Just goes to show you always have to keep an open mind. I really thought advance meant heat but I suspect with much higher compression on the 'new' engine things changed. Efficiency and all that...

This is very interesting. 20° is a decent temp reduction. Would you mind sharing the advance curve? Just for posterity, whatever that is.

Thanks

I have the non-bluetooth 123dizzy. It is set to the advance setting and the right distributor for a 73 2.0. I think the curve is published online. Sorry I can't be more help there. I think the vacuum advance is 10degrees or so at 11 - 14inhg.

I believe the timing was at 27 or 28 on my old setup, so a couple more puts me at 30ish. Again, can't be more helpful at the moment because I put a new fan on and my marks are... Hard to find...

Let me give some temperatures.
Drove 100 miles yesterday after I got the engine back in. Through the hills and valleys of the finger lakes in upstate New York.

Cruising at 60 I was at 350-360.
Climbing it would rapidly rise to 380 and all the way to 400 on not even terrible slopes. Keeping it in 4th would keep me at 385 or below but I was babying it. On my old setup that wouldn't have even happened at 70 on the interstate climbing a hill.

In town it was running 320 to 340 at 30. It would also heat up really fast. I am talking about cold to 250 degrees in three blocks. That would take 15 minutes of driving before.

Added the advance and it went to 280 cruising around town (in stock condition that would have been 265 no advance). Top temps 320, mostly around 308 driving it 'spiritedly' like I normally do. Calm driving brought it down to high 290s quickly. This is also on a fully warmed up engine after some hill driving.

Hill driving (600 feet in 1 mile) resulted in 375-380 but not rocketing towards 400.

The big test will be hitting the interstate tomorrow.

These are also brand new rings, valves, cylinders, pistons, etc so the fact I am breaking it in probably also affects things.

Funny...in another thread you stated you had the Bluetooth version and not the switched version.

There is a video on the 123 website on how to set both the centrifugal curve and the MAP curve (Manifold Absolute Pressure) on the Bluetooth version. Read it last night since I was not aware one was available for D-jet.

No, I said 123 offered Bluetooth for the 2.0 about 2 years ago. I got a discount buying up old stock... or at least I tell myself that.

This is really interesting - I appreciate the continued data and input. I'm away from the 914 for a few weeks again but i'll be monitoring this - and ordering a 123 - probably bluetooth version because it's only money.

Bluetooth is the way to go. You will not regret the 123. Best thing you can do for an old engine with points and weights. I have never ever regretted it.

Thanks for the information Emery

So just to be clear, you bumped up the timing to 30° advance from 27-28 and saw those increases in head temps, yes? I’ll have to check the profile, I may be at 30° also. Appreciate the help, I’ll take head temp reduction any day

I’d also think your temps will drop some after break in and oil change. Are you planning on using 10w40? Did you replace the engine tin seals?

Some lovely driving up there, pretty country. Not so much here on this overpopulated sand bar...

And yes, I don’t think anyone has regretted getting a 123. Fits the old “Buy once, cry once” adage. Eliminated so many issues for me, and adds a security aspect by being able to kill the ignition with the app.

The temps dropped after I put the vacuum advance back on. I am not entirely certain the added mechanical advance did much for temps.

I just took it on the interstate and it was 5% hotter than before the upgrades were installed. Before at 70 the hottest it would get climbing the hills into town was 380ish. I was hitting 400 this morning. Cruising at 70 in the flats used to be 360ish, now it's 380ish. At one point I hit 415 pushing it.

In town it's down at 308 or so. Up to 320 when pushing it.

It's about a 5% increase in displacement and nearly a full point of increased compression, so I might just be stuck with it....

Edit:So... Had many issues with this temperature thing, here is a thread that clears them up... http://www.914world.com/bbs2/index.php?showtopic=367004

Ok, thanks. Had to go look to see if there was a vac attached, there is. It’s got 9:1 compression, which no doubt adds to my temps some, especially at sea level.
Haven’t checked the advance curve yet.

I know my engine tin seal isn’t 100%, I hope to pull the engine in late fall to get rid of the oil leaks, and replace the seal. Hope on that, too.

I try my darndest to keep the head temp under 390°, which is usually going up a hill in 5th on a warm day

I am super happy that mine hasn't leaked at all, 175 miles now. My tin is all good and I don't have any missing seals. Sad thing is it has been pretty cool the past few days since the engine went back in. 70 or so.

Please know that if you buy the Bluetooth version...there are two "curves". The centrifugal curve which is emulated by the electronic dizzy and then a "MAP" curve or profile which is based on vacuum and hence the port on the side of the dizzy. You should address both when and if you decide to get that version of the 123.

Like Brant stated before...and has been my experience....not conjecture.. that most MPS in stock config run lean on part load so make sure the engine is checked with an AFM before you set the MAP curve. Outlined in the installation video on the 123 website there are stock curves based on Ve and engine design available. Because your's has been opened it has possibly been adjusted already but check.

Like Jake Raby used to post all the time: "Give the engine what it needs" I'll add to that...don't give your engine what somebody else's engine needs.

Good Luck