Least to most expensive 911 engine (air/oil cooled) to rebuild and why?
 

Hi - as a companion question I'd like to ask for your thoughts on what the least-to-most expensive 911 engines are to rebuild and why?

I assume a 2.7 would be relatively high on the rebuild cost side due to expected case work?

Thanks!

The SC motor is the easiest and least expensive. Well, if you have Mahles and no major damage that is.

My recent rebuld of an SC motor had a case, crank, rods, and cylinders that were in spec. A straight forward rebuild.

Ballpoark and assuming you're buying a core engine and doing a 914 /6 conversion they all cost about the same.
Thing is there's so many ways to build a /6 it's hard to give a definite answer on this.
I too prefer the SC and 3.2 because of the aluminum case, but many like the short stroke engines.

Thanks guys. Are the early smaller displacement engines like the 2.2’s in the “less expensive”to rebuild bucket?

Not looking to build a screamer-just a healthy and long lasting engine. Seeing that I already have a 2.7 it’s probably the route I’m going to go but keeping options open at this point it seems like a good idea, as does the continuing education you’re all providing.

Thanks!

I did a 2,2 MANY years ago and my case did not need a line bore back then. Now days I imagine some if not many of the 2,2 cases will need the works.

The 2,2s will most likely need cylinder work and new pistons, since they have iron sleeves. My old 2,2 also needed the heads resurfaced.

So, in general, the 2.2 won’t be that much less.

The reality is they are all a crap shoot once opened up. What is your goal? How much work are you going to do yourself?

You may want to sell what you have and look for a different core. A few years ago, before prices went stupid, and after searching for several years, I found a COMPLETE SC motor. I looked underneath and saw it had Mahle cylinders and reached for my wallet. Luckily, it was in good shape overall.

Determine what your goals are and set up a spread sheet of all the numbers and go from there. Remember, if you do it right and don't cut corners, it can be an investment.

Thanks for the follow-up and considerations.

That may be a good path to follow.

One more thing to consider about the 2,2s is the T had a non-counterbalance crank. That non-counterbalanced crank had it's pluses and minuses.

Ha-I wasn’t aware of a difference, let me go do some digging. Thanks for bringing it up.

I think you have to look at the costs of the builds but you really need to look at the intrinsic value of the core 2.7 against the 3.0.
A 2.7, no matter how much you put into it, buyers still look at it as a core
A 3.0 refreshed and running will always have more than a core value. Even if it is a core it value is still 3 times the 2.7
Bruce

Even if the 2.7 rebuild work is done properly and documented?

Track, I'm sometimes a little dense; may I ask how you identified the Mahle cylinders?

Mahle has 11 fins on cylinders while KS has 10
Visible from underside or pulling the air channel
Bruce

Thanks Bruce! That's very interesting. Nice to learn something new!

Just did my third 7r mag case rebuild. No case work needed on any to date. Granted I haven't been doing 911 motors for all that long, that's a good track record. I'd still prefer a 3L, but I see nothing wrong with a straight 7r.

If I may, I believe flatpac implicitly meant ..... engines with any significant miles are a crapshoot, the 2.7 significantly more so than the 3.0.

OK - that makes more sense.

No pulled studs etc ?

Not a one on the 3 I've done so far. Regardless, I still removed all the studs and had a machine shop installed case savers ($500). Used the original steel head studs on all of them. 1 is a very abused 2.8 track engine too AND that engine has cast iron (shock, horror) liners. Runs absolutely fantastic. I recently swapped that one to a DC80 cam.