3.0 CIS Engine Swap Complete

[RallyJon]

I just got back my ’71 after a long visit to the shop to have an ’81 SC engine installed. It took longer than expected, and (of course) there were a few unexpected issues, but the result is a much quicker car that drives better in every way.

The engine came from a local Pelicanite. It’s a 930/16 rated at 180HP. With the SSIs I’m guessing it will be more like 190. It had <60k miles on it and was in great condition.

The work was done by my regular mechanic, Bert Arano at Union 7 Motorsports. This is his second 911 engine swap, and his first time with 911 CIS, although he knew the basics of CIS from the older VWs he used to work on. As usual with new and interesting projects, he tried not to charge for his learning curve. One advantage (or disadvantage, depending on your perspective) of not using a “Porsche-only” shop, is that Bert is always focused on finding a solution that works, whether it’s 100% by-the-book, or not. Bert also charges $75/hr labor and orders parts from Pelican, instead of $90-100/hr labor plus parts markup at local Porsche shops.

After much consideration, we decided to keep the CIS for the time being. Bert’s an Autronic dealer and knows that particular EFI system very well, but it would have added another $3000 to the cost of the swap. Given that we’re working with a stock SC engine, that sum seems a bit steep for a couple of more horsepower and better drivability. Maybe later.

I know I was very apprehensive about the scope of the project going in. For the benefit of those considering upgrading an early car, here’s a rough breakdown of what it took to get the SC motor running happily in the older chassis.

Beginning: Pick up motor, check leakdown, replace seals, gaskets, clean up motor, backdate heat, install SSIs, delete emissions.
Parts: Misc gaskets, seals, spark plugs, etc.
Labor: 3.9 hrs. $248.

Fuel System: Replace all soft lines, fabricate hard lines and install CIS fuel system; drain and check fuel tank.
Parts: Fuel lines, pump, filter, accumulator.
Labor: 8 hrs. $600.

Electrical system: Rewire and adapt harness, senders, O2 sensor, fuel pump relay, replace connectors, weatherproof.
Parts: Connectors, relay, O2 sensor, wire and terminals.
Labor: 7 hrs. $525.

The Swap: Remove old motor, adapt oil system, throttle linkage, replace clutch, resurface flywheel, install new motor, adjust.
Parts: Clutch disc, lots of little stuff.
Labor: 6 hrs. $450.

Total parts bill: $1,114, includes all the above, plus any misc stuff that Bert found and decided to replace during the swap. Parts were sourced primarily from Pelican, but also a few little things came from Stoddard.

Total cost of swap: $2,937.
Engine: $5,000.
Est value of old engine: ($2,500)
So, to add ~50hp to a 911 cost me $5,437. To add ~50hp to my Subaru costs $500. Hmm.

Unexpected Side Project: Replace Torsion Tube. I posted pics of this separately.
Used torsion tube and adjustable spring plates. $475 (junkyard)
Labor to make jig, cut out old tube, weld in new one (includes engine remove and replace) and reassemble rear suspension. 11 hrs. $825.

Expected, but annoying, extra expense: (another) alignment and corner balance at Dougherty’s. Took extra time to fiddle with the new rear suspension arrangement. 10 hrs. $900.

Click for big pictures:

[LakeCleElum]

RallyJon: Thax for sharing this valuable info. Many of us with the older 911's will consider this swap when our engines wear out. I know it seems like you went thru a lot, but not much more than a good rebuild of your old 2.2 really! Good job...

[KobaltBlau]

Originally posted by RallyJon
So, to add ~50hp to a 911 cost me $5,437. To add ~50hp to my Subaru costs $500. Hmm.

Ah, the magic of turbochargers...

[chuckw951]

Great news about getting the swap done.

Now you just need to post some engine bay pics!

[RallyJon]

I know there has been some debate about how much weight a swap adds to an early car. Since I had the car corner balanced before and after the swap, I have some very accurate numbers.

Note that each corner has 17lb of hardware on it for the alignment/balance. Also, a driver weight of 250lbs is assumed. So deduct 318 lbs from the total to get the actual weight of the car. 1/2 tank gas was in the car both times. Same 901 gearbox for both.

Before: 2.4 w/webers. SSIs. No A/C.
Total weight 2371
LF = 485, RF = 447 (39.3%F)
LR = 744, RR =695 (60.7%R)

After: 3.0 w/CIS. SSIs. No A/C. No heater blower.
Total weight 2471
LF = 489, RF = 456 (38.2%F)
LR = 789, RR =737 (61.8%R)

EDIT: Car weight with 1/2 tank gas before = 2053lbs. Car weight with 1/2 tank gas after = 2153lbs.

[}{arlequin]

to save people time, by my math, looks like the car gained 100lbs.

[KobaltBlau]

Wow, dave. That really saved me some time!

[}{arlequin]

in retrospect, this is even funnier now LOL

just think of all the things you could do in those 30 seconds