911E into a 911T

[flipper35]

I have a 911T with no motor. I bought a 911E (MFI) motor and am ready to install it. My question is: Other than a MFI fuel pump and some new fuel line, are there any other issues?

Also, being new to 911s, what does is CIS?

Thanks, I appreciate it.

[86 911]

Flipper35, I can't answer your question on the MFI, but here is a great link that tells you about the CIS:
http://members.rennlist.com/jimwms/CIS/CIShome.html

[ckissick]

Depends on the years. Mostly electrical. What years are the car and motor?

[flipper35]

Thanks for the link.

The car is a 1971 and the engin is a 1971 also I believe. It's a 2.2l MFI anyway. It looks like there is an extra selenoid on the panel in the engine bay that I need that I don't have. Are all the basic electronics there or is it a different wiring harness?

[randywebb]

A summary:
CIS is an injection system controlled by air flow. It is often called 'mechanical' but isn't really. It has sluggish response and requires low compression. Fuel is sprayed continuously (hence the "C"). It is also termed K-jetronic by Bosch. It provided decent emissions control and good fuel mileage. It was a good system in its day, but cannot compare with more modern systems. Nor can it compare - for sporting purposes - with MFI or carbs. I am a known CIS hater, and have destroyed two of the systems, so far....

In MFI, the control is mechanical - you move your foot, it injects fuel. It offers better emissions control than carbs. It is a high performance, sporting system but has been superceded by modern EFI (electronic) systems. MFI can be tough to set up, service and repair. But people have pretty much figured it all out and can get docs to you (Check, Measure, Adjust) and help with any issues you have. It is hard to alter it for a different car 'cuz you need to find (or make) a different space cam. It has a sort of choke 'thingie' in it that alters fuel mixture based on air temperature near the base of the unit (which should be about the same as the temperature of air flowing down the tubes). They may have a cold start injector too, I think. If MFI gets out of whack, it has the mean habit of addign raw gas to the oil. Raw gas does not lubricate well...

Carbs are crude but effective devices that dump gas into a stream of moving air. The Weber (and its evolutionary offspring, the PMO) is the acme of carburetors. You get no choke on these and they aren't the cleanest or highest economy items, either. They are easy to tune (well, relatively easy) and can be field stripped or repaired. They are beautiful, sound great, and take up the least space or wt. in the engine compartment. They are a lot cheaper (to the extent that anything costing 3 grand is 'cheap') than aftermarket EFI or modifiying and rebuilding MFI.

[Paul Thomas]

Well said Randy.

I put an MFI motor in a T. I had all of the electric panel stuff, i did have to add a return line to the gas tank though.

Paul

[Todd Simpson]

My '71 already had the return line so you may be OK there.

Routing of the fuel lines has created some debate, check these diagrams.

MFI Fuel Starvation...Out of ideas.....help please

[flipper35]

Looking at the picture of the panel in the engine compartment I think I am missing the part next to the rear window defrost relay and the RPM sensor. The picture says it is the Start Enrichement Relay. I do have the RPM transducer there. Thanks for the pictures of the fuel routing. I think I need a MFI filter and fuel enrichment solenoid and fuel pump then. And a bit of line.

[flipper]

I will gladly sell you my CIS, Pay no attention to the CIS haters.......I am only selling mine..because..umm...I need to adopt a third world child...yeah, thats the ticket....CIS rocks...no really

[flipper35]

I already have a '71 E motor, just need to put it in. Wanted to know what all I was missing. There were days I would gladly sell the car as is but I am doing much better now. I was glad the interior had just been re-done and there is little rust. Mostly in the headlight buckets.

[flipper35]

One more question. I need to get bolts for the transmission mounts. They look like a 12mm or so, does anyone have the size and length.

[flipper35]

OK, one more. I need to know the length of the 10mm bolts for the half ahafts also since I don't have any of those either.