Just picked up a '71 with a 3.0 project-question about CIS

[POORSH]

I just picked up a '71 with an '83 3.0 but with a '78 CIS intake system. The PO bought the 3.0 without the lambda, so he then picked up a '78 CIS to make up for the absence of it. The car has sat for 8 years because the '78 CIS is having issues with the '83 motor. I haven't attempted to start the motor yet, but wanted to get your inputs on what I need to do before I start it. I've tried looking for a set of carbs but have not been unsuccessful up to this point. Can I get the '78 CIS to work with the '83 motor? Mandatory pic.


thanks.[IMG][/IMG]

[Laneco]

Others can chime in as to "how" to get it to work, but don't forget this point...

78 and 79 are are "big port" runners for the CIS. 80-83 are small port, each with heads to match.

angela

[snbush67]

I think the 83 Euro engine has large port intakes, so it will work if it is a Euro.

I think by putting the large port CIS on a small port engine the step down to the heads may cause some turbulence in air flow.

[T77911S]

you can always pick up a set of small port runners, although i dont know if you would have to change airboxes too, but i would stick with the the rest of the 78 CIS. i have a set, along with an air box.

since it has known CIS issues, i would start by pullimg the system off, replacing ALL the rubber related to the CIS, including the injector sleeves, and inspecting the air box and make sure it is not blown, (if it does not have a popoff valve. install one if it does not).

first i might go ahead and check fuel pressures, along with residual pressure, just to check out the WUR so i would know if i need a new one.

its sometimes better to replace stuff like this because if you have problems, you know what has been eliminated, plus, you wont have to replace it in a few years as air leaks develope.

[Gunter]

US '78 CIS on top of an '83 bottom works great PROVIDED the heads were ported to match the larger intake runners.

Another bigger problem is that sitting for 8 years is bad because, unless the PO ran injection cleaner through the system before storage, the inside of FD and the injectors may be gummed up.

Hopefully, it was stored with a full tank??????to prevent rusting inside.

Tank needs to be drained and possible cleaned out, new fuel, new fuel filter, inspect airbox and intake runner sleeves........................
If you don't clean out a dirty tank, the fuel pump will be kaput in no time.

On second thought, I'd take the CIS off to see if the heads were ported for match-up, replace rubbers sleeves and gaskets, check the airbox, install pop-off valve if it doesn't have it, replace vacuum rubber lines.............

[POORSH]

[QUOTE]US '78 CIS on top of an '83 bottom works great PROVIDED the heads were ported to match the larger intake runners./QUOTE]

I don't think they were matched, but I will look into it.

Thanks to all who have chimed in. I have some work ahead of me.

[Gunter]

Yes, some work but worth it.

For best performance, you'll want a good '78-'79 ignition distributor 0 237 306 001 or re-curve the 0 237 304 016 to run without vacuum.

Remove the injectors and soak them fully submerged in injector cleaner for a day.

When all is done, use 2 cans of Techron on a full tank to clean out the fuel distributor.
Hopefully, it won't be too gummed up.

Enjoy.