Help!Is the stock EFI enough, 74 EFI ?'s Options

[Gunn1]

I Recently purchased a 74 914 (VIN 4742901009) with what I believe originally had a 2.0 liter installed in it (original engine ID 006765). According to the seller the stock engine had one of the cases busted when it had thrown a rod through it. He went on to say he purchased a case (W0111578 ID found in front of oil filler) and took the remaining parts from the original engine to a shop here in MPLS. there they replaced the main, rod and cam bearings. Blasted-polished the crank and rods. installed a 30mm high flow oil pump. Honed the cylinders & installed and gapped new 94mm ring set. Replaced worn camshaft with a new "IV" mechanical cam. At this point the car is not drivable for structural reasons but the engine starts idles, throttles up down and sounds pretty good. The car came with what looks like the 1.7 type air filter set up and the throttle body which sets horizontal rather than the typical vertically positioned throttle body with the larger square type air filter set up.
With all that important info out of the way, I have many questions. Is this a 1.7 injection installed on a 2.0 engine? if it is, is it a huge deal? Will the 1.7 injection automatically adjust to the larger engines demands for fuel. Most importantly what specs do I use to tune the engine? Thanks Gunn

[r_towle]

No, it will not autmatically do anything, it's from the 70's.

Basically there are several hard coded (hardware coded) air/fuel maps.
Cold, warm, and hot.

To tune it you will want an external air/fuel meter with either an 02 sensor installed, or what I do is stuff an 02 sensor into the muffler.

This will give you a better understanding of how the motor is running.
You will not get a good set of readings unless you do this under load, driving or on a dyno, because one of the main sensors is manifold pressure and that changes dramatically under load.
The rest of the sensors are simple to test with a multi meter.
Read this site attached, it's considered the bible.
http://members.rennlist.com/pbanders/DjetParts.htm
Rich

[poorsche914]

Post some pictures of the engine/engine bay so we can see what parts are being used.

And... (IMG:style_emoticons/default/welcome.png)


(IMG:style_emoticons/default/driving.gif)

[Gunn1]

Picture as requested.
I know its sort of a mess....No one ever said it would be easy!

[r_towle]

Find the numbers on the ecu, mps, tps, and cht
They all need to match per the charts on the site I posted

If you don't know what those acronyms mean it may help reading the site I posted

[Gunn1]

Picture of ECU.

r-towle, I will read the article and get the numbers of the ECU, MPS, TPS and CHT. Thanks

[poorsche914]

If engine is original to the '74 body, spark plug position suggests the engine most likely started out as a 1.8. Double check all the FI pieces to verify exactly what you have.

(IMG:style_emoticons/default/driving.gif)

[3d914]

gunn1, here's a link to a site with all the 914 Fuel Injection part numbers ans associated years. Also includes diagnostic info. Lots to learn, but well worth it.

http://members.rennlist.com/pbanders/djetparts.htm

Welcome to the madness!

[Gunn1]

Gents

This is what is currently in the car, and how the ID numbers correspond with the numbers in the D-Jetronic Parts Analysis and Troubleshooting
ECU=
022 906 021 E (Bosch 0 280 000 037) ECU use only with the 1973 2.0L engine.
MPS=
022 906 051 C/0280 100 037/use on 2.0L 1973 NLA. GA0 000 001=>GA0 006 765
TPS=
039 906 111 A/0 280 120 032/use on 2.0L 1973-1976
CHT=
311 906 041 A/0 280 130 012/use on 2.0L 1974-1976

Sort of looking like the car was a 2.0L and when the engine was replaced because of the broken case they used a 1.8 or 1.7 case ?

Remember the ID number on the case WO111578? what does this ID equate to for information?

Thank you

[jcd914]

3 or 4 studs on the head to intake runners?

If the original 2.0 threw a rod and busted the case the cranks would \probably not have been usable. the W code engine they used as a core would have had the 66mm crank used in a 1.7/1.8.
You could have a 1.7L/1.8L engine under all those 2.0L D-jet parts.

Just a thought.

Jim

[jcd914]

Oh and (IMG:style_emoticons/default/welcome.png)

[Gunn1]

Thank you for the welcome to 914 world....

The engine has 4 bolts holding down each of the intake runners, 4# for the left cylinder bank and 4# for the right cylinder bank.

[ndfrigi]

Picture as requested.
I know its sort of a mess....No one ever said it would be easy!

Welcome to 914world!

Your engine is not really that messed except that firewall pad. You can just delete/remove that pad so you be able to see if there is some rush on the lower firewall area that needs repair.

[Gunn1]

this photo was taken by the previous owner.

Its the only one I have of the engine after the rebuild, before it was reinstalled in the car.

[Gunn1]

Hold the phone on the 4 versus 3 bolts holding down the intake runners.....I may be wrong looked to quick because of the snow that's currently falling!

Will get a better look tomorrow....

[Dave_Darling]

I Recently purchased a 74 914 (VIN 4742901009) with what I believe originally had a 2.0 liter installed in it (original engine ID 006765).

There should be one or two letters on the beginning of the engine ID.

A "Certificate of Authenticity" would tell you the original engine serial number and original engine size. Talk to Porsche to get one, and bring money. You can also look for the emissions stickers in the engine bay, which will list the engine size.

... he purchased a case (W0111578 ID found in front of oil filler) ...

W would be an early-ish 1.7 engine. The stamp being in front of the oil filler means it was from a VW, likely a 411.

It is most likely that the engine still has 1.7 heads, as the 1.7 style manifold takes a little extra work to bolt up to the three-stud heads. (And if the 2.0 parts are available, it's easier to use them.)

I can't see in the photo if the injectors are green or yellow. 2.0 injectors would be green, 1.7 ones yellow (or rarely black).

Note that it is possible for a D-jet engine to run with mis-matched parts, but it likely won't run correctly in at least some circumstances.

--DD

[Gunn1]

The runners use four nuts for attachment to the heads. I do have a cert of authenticity from Porsche, which the last owner gave it to me when I purchased the car. 006765 is what the cert of authenticity says no letters appear in front of this number on the cert.
I will look and see what I have for injector colors later today. I can already tell his is going to be fun!

[Gunn1]

Gents,

(IMG:style_emoticons/default/WTF.gif) Ok so I spoke with the gentleman that rebuilt the motor.

He says the engine is a 2.0 liter in displacement.

He explained that when he rebuilds these engines if the cases and heads are junk or to far gone, he uses 1.7 liter cases with 2.0 cylinders and 1.7 liter heads(which explains the 4 bolts on the heads for the runners versus the typical 3 bolt design normally found on the 2.0 liter). He say's he then "opens the heads and case halves up" or "fly's" them on a Bridgeport lathe, that way everything assembles correctly and makes it a 2 liter in displacement. Guessing that explains why the engine runs with all the 2.0 liter electronics on it.

So does this mean I can treat it as a 2.0 liter and build accordingly? Suggestions?, Bueller, Bueller, anyone, anyone?

[914time]

Welcome to the the World, Gunn!

We have a couple of 74 2.0s in the garage in St. Paul. One of the 2.0s maybe for sale.

PM me if you're interested-

[r_towle]

You can use any case with no modifications for all three sets of cylinders.
You need to mill out the 1.7 liter heads to fit the largers cylinders.

The valves, and ports are very different on the 1.7 liter versus the 2.0 liter heads so those heads will never flow like the 2.0 liter heads.

I would suggest for the sake of costs that you get an A/F meter and see how it runs and if the mixture is right.
You will most likely have to be using a custom Djet setup to make it work properly.

Rich