What's up with the 2,7L engine, really ?
 

Hi guys. Spring is coming slowly and the 911 disease is coming back to me...

I would love to add a second 911 to my collection and there's a 1977 911 for sale in my area. This very same car has a special meaning to me because my dad nearly bought it more than 15 years ago, but ended up with a '72 911E, that he sold a few years ago... :(

Anyway, I'm wondering if the 2,7L is really a problematic engine, as we often read. I would like to know the real deal from 2,7L 911 owners.

There you go.

Nic

I've got a '74 and love it. Street, track, fun car. So....the 2.7 does / did have issues. To properly address them you have to, or the previous owner has to have done a complete teardown to put threaded inserts where the head studs go into the magnesium block. Do that, get rid of any AC, make sure you've got the 11 blade fan and at least a trombone oil cooler and you're good to go. If none of that has been done, in todays dollars it's probably cheaper to find an SC engine and do the conversion. You'll have a different car, but loads of fun nonetheless.
Then there is all the suspension and brake work needed on a nearly 40 year old car....
-C

I've had the 2.7 in my 74 911 and it never has problems...Love it. Pulls hard.

74 good exhaust system (same as earlier years).
75 they changed the exhaust system due to emissions and there were all kinds of heat related issues causing head studs to pull.

I just sold the 2.7 out of my 1975. Not because of problems, but in a quest for more power (3.6 worth).

The top end was redone with case savers and new studs, hydraulic tensioners, pop off valve, turbo valve covers, and headers. It ran great with no problems at all other than a few oil drips here or there. The guy who bought it will be very happy. The moral of this story is, all the original heat and other issues have been identified and now have easy fixes. Done right, your 2.7 will be bulletproof.

Hydraulic tensioners, pop off valve, turbo valve covers............10 years and going.

The "biggie" as I see it is most people will say that if you need a rebuild then just upgrade to a larger/newer engine.

I'm sure the 2.7 core is worth something as a starter for someone interested in that class (2.7 - 2.8 dual plug). However, if someone is thinking of a total rebuild it's typically for a culmination of reasons.

Like others have said, the obvious drawbacks are pretty easily fixable. The '77 case has all the latest oiling mods from that time, so you can't get a better case in terms of that. I have a '77 engine I will put in my car when the time comes. It has a bunch of the normal mods: turbo lower valve covers, "E" cams, Nikasil cylinders, JE 9.5:1 pistons, plus I had dry film lubricant coatings and thermal barrier coatings done, along with a number of other things. I expect it to last longer than I need. I also have another '77 core engine I will probably sell along with the CIS, etc. sometime. If you want a 2.7L the '77 is supposed to be the best one.

The 2.7 case is made of Mg which flows like "congealed butter" (to quote Bruce Anderson). This is much, much worse if the engine is run with the dreaded thermal reactors and esp. in a hot environment. They were installed as an early form of pollution control and problems are common in California.

AFAIK, they were never used in 1974 (anywhere). They were used in some places in 1975-on. My '75 never had them as it was imported into Portland. I'm not sure what Canada cars got or when they got it.

A Mg cased motor that ever had thermal reactors on it should be torn down, carefully measured by a machinist familiar with those particular motors, and will often need to be align-bored. I won't say that not doing that is like driving a grenade... maybe a smoke grenade. So there is a substantial risk premium attached to buying most 1975-on 2.7L cars.

The cost to really prep one right is high and many elect to just plug in a 3L or, better, a 3.2L with EFI.

Other than that the problems are just the sucky CIS FI stuff.

The 2.7 is a fine motor. They got a bad rep. starting back in the early '80s. There were a couple of specific problems. These were known early on, and were not particularly difficult to fix. But people tended to fix them cheaply, not correctly. Dealers band-aided them to get them out of warranty. A well known author warned everyone to stay away from them. Just sort of snowballed to the point today where many believe there is something inherently bad with the 2.7.

Get good valve guides. Put thread inserts in the case. Use the right cyl. studs. Use Nikasil (not alusil) cyls. Plug the air injection ports. Ditch the thermal reactors if present. Add front oil cooler lines if not present. Make the oil scavenge mod. There's a few easy tuning tricks with cams and induction. Use an 11 blade fan. And then you have a really nice and long-lived engine. Personally I prefer the feel of the 2.7 over the 3.0 and larger motors.

Oh, and I sold my '76 911S many years ago. Cockney brown. Perfectly stock. All the required fixes had been done correctly. It was smooth, fast, reliable, and just a really pleasant car to drive. I've always regretted that decision.

Thank you guys, very informative.

My old car had a built 2.7 from a '77. It was modified, and made somewhere around 210 hp at the flywheel. Drove it hard, and it never let me down. I've been tempted to pick up a '77 coupe and make a hot - rod with it. I'd go with the same spec I had in the old car.

If it's still running chances are it's been sorted. The key is to make sure it was sorted correctly. I picked up my cherry 76 with a 2.7 built to RS specs. It's bullet proof thus far and could not be more please. The bad rap these cars gets is just silly IMHO. If you love it and it's in good order with the proper docs get it.

2.7
 

Isn't a 911RS powered by a 2.7? Once they've been redone with case savers, they are quite bulletproof and a very nice engine.

It used to be that the 3.0SC engines were much stronger and so more desirable for the aluminum crankcase, but now that most of them have been having issues with breaking Dilivar head studs, I don't think it makes as much of a difference.

The 2.7 that Supertec built for my 914-6 conversion car just pulled 199.56 hp at the rear wheels (RS pistons and cylinders, S cams, Weber carbs). Not too bad for a 40 year old design!

yes - they are fine motors if you spend the $$ and more $$$ to bombproof them

or you can buy an Al cased motor and hotrod it - after years of study, I decided to do the latter

concours people will need to stick with a MG case

the statistics tell the tale, not the anecdotes

you can certainly drive one around until it has problems or you can do things the Porsche way

I had a '74 2.7. Loved it. Had around 100k on it when I bought it. Car had a trombone cooler, Koni's and sport seats. Didn't drip oil AT ALL. I wish my POS '82 sc ran as well.
Carter

Yes you can, and as long as they are maligned and undervalued you can do so very affordably.;)

Like many reputations of all sorts, half (or more) of what is believed about 2.7s is fiction. It's like anything else, something alarming happens and hits the news at some point, and then that alarming quality is the 'truth' about all other specimens of the thing. It doesn't matter if you are talking about car engines, or coconuts, people tend to tar them all with the same brush - it makes their lives simpler being able to assign one notion to every example of something. It's an unreliable prejudice.

I have never seen solid numbers quantifying 2.7 failures, just vague proclamations. What stats? They are not all bad, and never were - it's a myth.

As is often pointed out, every engine series within the timeframe that this forum considers has had 'issues' of differing sorts. None are perfect. My 2.7 has been rebuilt with the complete list of 'corrections' and 'updates' always mentioned here and it runs great. Did it actually need them? I don't know, but it runs fine now and is plenty fun. The rest is ancient history.

My dad purchased the 74 new. 10K miles and 10 years ago, he had it rebuilt by Schneider in Santa Barbara for the princely sum of $13k.

The car had no front cooler, but it did have AC and it ran some frightening oil temperatures with just normal driving.

I inherited the car and quickly lost the AC, so I could install an 85 front fender cooler. This is a must do if the weather is hot.

Have someone who knows 915 transaxles give the car a good listen. Mine has noises and I'm afraid I am looking at a $3000+ rebuild.

I am currently doing a complete front end rebuild and looking forward to getting it back on the road.

Oh yes, on any car of this era, beware the tinworm. Again, have someone who knows the 911 give it a good look in all of the wrong places :-)

hth,
chris

It's funny that statistics have been mentioned above as an argument against these engines, because there aren't any. People take vague impressions and start to believe there is a thorough understanding of these things. Take intermediate shaft issues on 996 engines, for instance. I know a guy who will tell you all day long that well over 50% of all 996 engines produced fail due to this issue, yet the most authoritative study I have found concluded that 1 - 2% of engines actually had this failure mode. People read the forums, hear about the issues, and it suddenly is imagined to be a much larger problem than it really is.

My daily driver is a 13 year old TT, and if you read the comments on Edmunds, for instance, you would imagine it will blow up before you get to the end of the block. Reality is, it's been a fantastic car, and based on owners I met, that is the norm.

On the plus side, due to the irrational panic these things generate (and the internet has only increased the problem exponentially), there are still some cars out there that are undeservedly bargains. I'm looking again at building a hot-rod, and you can bet it will be a '74 - '77 car because they are great cars at a great price.

I also had a 1974 911 (Carrera 0440); it ran great all the time never had any issues...just jump in and start it up. I would recommend a front radiator oil cooler for hard driving and hot weather.

Rahl