The euro '80 and '83 heads appear to be exactly the same. I also have '79 euro heads, but they have the shorter exhaust studs for thin flanged heat exchangers. All of these euro heads have the air injection holes.

-Rob
1980sc

Thanks, that all makes me feel comfortable that I did the right thng boring out my intake ports. When I rebuilt the engine I set the cam timing close to the 930/10 specs. This was partly because I needed to retard the valve timing to meet Wayne's suggested valve to piston clearance values. With this timing and the intake port increase I have a
930/10 spec engine except I still don't know what the CR is on the pistons. (They are probably the 9.3:1 stock 82 US CIS pistons.) There was no way to visually tell without the 9.8:1 CR pistons to compaire to.
Thanks for your help on this and the WUR warm control pressure adjustment.
I have some continued tweeking to do on the control pressure and possibly a vacuum leak to track down. It run's good now except on deceleration the A/F swings way lean. This might have something to do with the deceleration valve or possibly unmetered air leaking into the system under that extreem condition.

I'll keep working it!
Thanks again!

It should go lean on deceleration. Saves gas. And you've got the right idea. The deceleration valve opens at high vacuum conditions (decelerating in gear) and routes air around the throttle plate. This causes the mixture to lean out and supposedly prevent backfiring. I've run with and without one, and without it the exhaust certainly pops more while decelerating in gear.

-Rob
1980sc

Rob, I disconnected and plugged the hose on the top of the deceleration valve. I noticed that the adjustable part which the hose connects to was screwed all the way out or up. I loosened the lock not and screwed the part all the way in or down. (Is,'t this the correct way to disable it?)
Anyway I also put a rubber cap on the top where the hose goes.

I popped the rubber off the top of the mixture control unit an dthe throttle body so I could see the position of the plate at rest. (It looks like it's where it should be.) I moved the lever up and down to check for any binding and it was smooth.

I double checked my hose connections which match thge vacuum diagram for the 78/79 US cars. This is a 83 Euro SC and as far as I know it's hooked up like the 79 US K-basic system. I bottoned everything up.

With the deceleration valve disabled (I'm pretty sure it is, the RPM's go right to idle without the blip when you lift off the pedal.)
I drove to work this morning.

The lean symptom on deceleration was actually magnified. I think that this is because there is a vacuum leak somewhere and now that the vacuum is not limited by the deceleration valve it's actually sucking unmetered air in harder.

My first suspicions are with the red plastic bushings that hold the injectors in the intake runners. I have replaced one in the past and have the rest but didn't finsh the job.

I recall that they have an O-ring that you can't see that is between the bushing and the intake runner. I devised an easy way to pull them out.
The originals were held in with 3 little punch marks that expanded the metal arround the slot that the ounch created. This is not easy to duplicate well. I actually think the one I installed is now loose. the o-ring should keep it sealed but I'm not sure. Is there any reason I shouldn't put some RTV sealant arround them to help them stay in place. I don't think it would make them more difficult to remove later.

Has anyone have a creative approach to this little project?
Another one of those "should have done it" while I was rebuilding!