Rebuild a 2.7 or replace with a 3.0 or 3.2?

[helgeseg]

I got a deal over the holidays on a 1977 911S. However, the motor needs some work. I've been reading up on the stock 2.7 motor and there appear to be some major design flaws. So I'm asking for advice on whether to get into tearing down the 2.7 or just replacing it with a 3.0 or 3.2. Any ideas?

Thanks!

[ttweed]

Keeping in mind that any advice you get on the internet is worth exactly what you paid for it, here's my $0.02:

The '77 model year cars are still subject to smog certification in CA. Therefore, any engine work you do will have to include all the pertinent smog equipment if you intend to license and drive the car on the street. I believe the '77 2.7 engines came with the infamous thermal reactors which caused overheating in hot climates when run hard. I'm not sure if there is a CARB-approved replacement for these exhaust systems, but perhaps someone with more experience with the mid-year cars than I can chime in on this. The magnesium cases were also fairly fragile in comparison to the later aluminum cases in the 3.0 and 3.2 engines. When rebuilding them, it is necessary to include a lot of expensive machining steps to insure longevity (line bore, case savers, shuffle pins, etc.) When combined with the usual rebuild parts and labor, this can add up to a very expensive overhaul.

It may be more cost effective to find a used 3.2 engine (complete w/ DME, catalytic converter and all CA smog equipment) and swap it out. You will probably come out ahead, cost-wise, and the difference in performance of the later engine is considerable. It is a bit of a crapshoot finding a used 3.2 in good condition these days, but they are out there if you look hard enough. You need to find one with low enough mileage and/or documented maintenance/rebuild that can be verified to have good compression and leakdown percentages, or you may end up needing to overhaul the used motor sooner than you would like. You will also end up with a used 2.7 engine to part out or sell as a core motor to offset some of the cost of the swap.

There are come folks that contend that putting any non-original engine in a 911 tends to devalue it, but from a collector standpoint, the '74-77 911 is not at the top of the list, so I wouldn't worry about that factor. A 3.2 swap may even be seen as a valuable upgrade for these models on resale, if that is a concern.

Good luck with the project, whatever you do,
TT

[Jad]

Another important question is what do you plan on doing with the car and what condition is the rest of the car in?

As a track car, the engine upgrade is great for performance, but puts you in a much higher class. As a street car, the bigger engine is more drivable, but could hurt resale.

TT advice is probably right on for most circumstances, but a little more background might help with further recommendations.

[Steve Grosekemper]

Keeping in mind that any advice you get on the internet is worth exactly what you paid for it, here's my $0.02:

Good luck with the project, whatever you do,
TT

And here is another $0.02 worth.
I get phone calls like this all the time and the fact is when a car is acquired for a "Really good price" there is usually a reason.

Let's say this is a perfect 77 911 that needs and engine overhaul.
Because of all the updates these motors need the cost of this is $10K if the case can be used and you still have a 77 911.

For that price you might be able to get a late 3.0L engine with a recent overhaul or top end installed.

So you now have $12-14K in the car, because it wasn't perfect and it's still a 77 911.
For that price you could have a really nice 911SC.

These projects usually don't pencil out unless you can do all of the work yourself or find a really great deal on a later motor.
(Which TT will buy up before you even knew it was on Rennlist)

[dougwierenga]

I have a nice 3.2 for sale up here in Encinitas. It is still in my car for PPI and road test.

Check out this thread: http://forums.pelicanparts.com/showthre ... ost2333851

The exhaust would have to be returned to stock, however for CA smog. It is in my early car which requires no smog. I could assist with this conversion and sell the other parts. Actually, I have a friend in SD who just took the stock exhaust off of his, so it is probably very simple trade of parts.

Doug Wierenga
760.487.1323

[helgeseg]

Steve,
Good call. The big reason I bought it is that I'm almost finished with the refirb of my '82SC and needed another project. The '77 has a nice slant nose kit and a really nice interior, so for $4500 I thought, what the heck!
Erik

[ttweed]

The '77 has a nice slant nose kit and a really nice interior, so for $4500 I thought, what the heck!

Erik-
With a slantnose kit on it, I don't think you have to worry about originality anymore! I'd buy Doug's 3.2 and make a hotrod out of it. A slantnose look with a stock 2.7 is pretty much a "big hat and no cattle" car anyway, just begging for more power.

Of course, as Steve said, don't expect to make any money on the project, but driving it should be worth the "fun tax."

TT

[Steve Grosekemper]

Eric,

Tom is correct, make a hotrod out of it with Doug's motor.
(I would snap that up in a heartbeat if I was in the need-great deal)

Having just finished my '83 911SC mechanical restoration I understand your need for something to do. You are as sick as the rest of us, and these projects are like therapy. Cheaper than a shrink...

Since you can do it yourself and with the price of Doug's motor package you could do this for a reasonable price. You could be the exception to the rule.

I have some ideas for you on the smog issue with dougs motor, send me an e-mail and I will give you the details.

Now get started on that thing so we can all check it out.