Porsche 911 "series j" 2.7l 1977

[AUSTmike]

hi guys, can anyone please help me out .i am trying to get specs and any info on the "J" series that was the last of the 911S G, H, I, J Series ~ 1974-1977. all i know from this model is it has a factory metal sunroof,it is 2.7 ltr ,5 speed manual. i researched some websites about this series and i couldn't find anything about it! is there anyone who owned this particular model or is there anyone who knows the insight to this model,ect did the "J" series have any engines upgrades to this 2.7 engine because of its last intro to this series?.. Is there any modifications done to the "J" series that Porsche did to improve its ways after the release of the "G","H","I" . the reason why I ask is I have an opportunity to buy the "J" series 1977 with a 2.7 ltr engine and average condition near where i live and was seriously thinking of buying it after i take it for a drive and check it right out!....

any info on this model would be much apprieated...thanks guys

[M.D. Holloway]

the J series was built from Aug 75 to July 76...nothing to mention that out of the ordinary: 2.7 lit, 2687cc, 8.5:1 comp ratio. I shall assume its an S cuz its a 2.7, Carreras were 3.0. Tranny is a 915/44.

The US, Candian and japanese versions had thermal reactors and egrs that many feel were problematic. My 77 is an ROW so it doesn't have them. The last in the series was the K. The tranny did get an improvment in 77 to improve upon 1st to 2nd shift engagement, the rear suspension received a two piece trailing arm to make ride height easier.

[M.D. Holloway]

Please fill us up with details and pics...this is good stuff. The 2.7s were considered the most maligned yet they are torquey little beasts. Not many were built - between 2000 to 3000 a year. Really small production run compared to todays standards.

[red77911s]

Hi there, I got one of those a couple of years ago and I'm still trying to figure it out, there does seem a lack of info on the mid year cars, the bad rap appears to be from a combination of thermal reactors and a five blade fan, the former holding more heat and the latter not providing enough cooling shortening the engine life. the solution seems to be backdating the exhaust and switching to an 11 blade fan. the good thing is they started galvanizing the bodies for these years and some people like them as they tend to not need as much body work. I know this isn't much but its all I got for now, my advise is get every book you can and read and you'll have to guess the rest. I think it would be nice to have a separate BBS for the early, mid year and later cars. Oh and my car hauls ass, yes a very powerful engine for the cars weight. Old cars take a lot of tinkering though, hope your mechanically inclined.

[Reifle]

911 and 911S 2.7 (1974–1977)

Model year 1974 saw three significant changes. First, the engine size was increased to 2687 cc giving an increase in torque. Second, was the introduction of impact bumpers to conform with low-speed protection requirements of US law, these bumpers being so successfully integrated into the design that they remained unchanged for 15 years. Thirdly, the use of K-Jetronic CIS Bosch fuel injection in two of the three models in the line up— the 911 and 911S models, retaining the narrow rear arches of the old 2.4, now had a 2.7-liter engine producing 150 PS (110 kW; 150 hp) and 175 PS (129 kW; 173 hp), respectively.

[Reifle]

Type
Flat 6
Induction
Normally-aspirated
Cooling
Air/oil-cooled
Valvetrain
Single overhead camshaft
Injection
K-Jetronic Continuous Injection System
Bore x Stroke
3.54 in/90 mm x 2.77 in/70.4 mm
Displacement
163.90 cu-in/2,687 cc
Horsepower
165 @ 5800 rpm
Torque
176 lb-ft @ 4000 rpm
Max RPM
6400
Compression Ratio
8.5:1

[Reifle]

Prices New:
$9,950 for 1974 911
$14,395 for 1977 911 S

[Reifle]

History of the 1974-1977 Porsche 911

The mid 1970s are sort of the forgotten years for Porsche in the U.S. (or at least the years Porsche wishes they could forget). Ever-tightening emission control laws played havoc with engine longevity from 1975 until 1977. Unbelievably, Porsche’s answer to smog regs was heat, thermal reactors burned exhaust gasses and they even removed some fan blades to raise running temperatures. Few 2.7 liter U.S. spec cars made it past 75,000 miles before the engines went kablooey. Experienced Porsche engine builders can fix these issues today, but not if the car still has to pass smog tests. It’s a bit of a moot point anyway as few 1975-77 911s seem to have survived. Other changes included the start of the so-called “short hood” cars which included 5 mph bumpers. Porsche did a far better job integrating these than most other manufacturers. In 1974 and 1975, Porsche offered a 2.7 liter Carrera but it was nothing like the Euro cars. It was mainly fender flares, decals and a rear spoiler. They had the same 160 hp motor as the 911S. Finally, from 1976 on, all 911s got a dip in a zinc galvanizing bath prior to paint. The result was the most rust-resistant 911 yet.

[Reifle]

I have a '77 911s and love it! What I like is that it has the narrow fenders. Mine came out of the USA and I am in Canada - Ontario. So, the galvanized body is wonderful as it has never been fixed. I don't drive it in the winter as they use way to much salt up here. The so called motor issues have be rectified on most mid - year cars. They either replaced them with 3.0 or 3.2 L. Mine is the 2.7 L rebuilt with all the necessary updates. The tranny is a bit different - shift slowly and all is just fine. No speed shifting... Like any 30+ year old car they need some attention and parts need replacing. Drive it and enjoy it! BTW - I did find some articles on the net and posted just above. Just some bits of information...

[AUSTmike]

thanks guys, really helpful info. do you know if the "J"series was an improvement to the other precesses (G,H,I) models... when I go to check out and drive this "J" model this weekend , I will take note if it has a 5 bladed fan ,but im hoping it has a 11 blade fan though. If it does have this higher cooling fan do you think that porsche updated some improvements in the "j" series after the (G,H,I) models? .Im really hoping that Porsche did do improvements in the "J" series on the 2.7 engine ,this will give me a little more confidence in making the decision to purchase the car...

[javadog]

You need to be a little more specific. Are you in Australia? Are you talking about a right-hand drive version originally made for Australia? If so, a lot of the comments that you will hear from members that have US-spec cars won't be valid. In the US, a '77 model had an engine that was quite a bit less powerful and more problematic than some of the engines that were available in 1974/1975, so they did get a bad reputation here. A car in Australia most likely will not have the same engine, depending upon how it was originally imported. There are lots of cars running around Australia that were imported from other markets.

Porsche made a few small changes and improvements every year over previous models. In 1977, they added face level vents in the dash and some minor changes to the door locking system. Some cars got a brake booster, depending on the market. Minor changes were made to the transmission synchronisers and clutch release.

There is nothing that is so much better on a '77 than previous models that I would consider makes the car very different. Condition and service history are far more important.

Some significant changes occured in the 1978 model year, which made those cars somewhat more desireable.

JR

[AUSTmike]

Yes good point on what country!, I am in Australia and I see many imports from UK and Germany. I have checked out some of these series of 1977 and they all seem to have a little oil leak in the valve stems is this a common thing with this series? after reading some info on the internet,some porsche mechanics states that this is common and not a serious issue with the 911 and boxter engine mainly because of the flat-6 design and gravity playing apart. also it was stated that many 911 flat-6 type engines have that puff of blue -oil smoke on first start because of the dry sump design compared to the wet sump designs in upright type other car engines...so my point is if i am testing out a 911 engine and i stand behind it when someone starts it ,i will listen for the rattle of the tensioners and check the volume of fume or smoke ,that if the owner hasn't started the car for over any length of time. Would the engine be still a good motor

[nickyclyde]

Sounds like you are trying to have us answer questions here that will let you know if this car has a good motor. Nothing wrong with that concept. But only a thorough PPI will tell you that. Ya really need to do one before purchasing the car you describe.

[javadog]

A 911 motor will smoke briefly after a cold start. Normal oil consumption is dependent on how it's driven but can be anything from 1000km/l or less. A "little oil leak" from the valve stems doesn't mean anything unless you quantify how much and it has nothing to do with the engine configuration or the dry sump system.

Really, there's not much you can tell from driving one, unless it smokes badly upon acceleration or deceleration, runs poorly and that sort of thing. Physical inspections by a mechanic, along with objective things like leak down tests are essential to really learning anything about these motors. A review of the service history is also important.

You need to have the car inspected by someone very familiar with the 911. Short of that, it's a crap shoot.

JR

[RWebb]

the "J"series was an improvement to the ones right before it only in terms of getting a tad more rust proofing - search up a thread on the galvanizing I posted years ago

buy The Porsche 911 story by Frere and you can read all about it

the SC in '78 was a huge step forward; the best US version of the 2.7L motor mid-years was the '74 due to lack of thermal reactors, but some 49 state '75s also lacked them like the one I used to have (now a BC car)

[djpateman]

There are a lot of Australian`s on this site. And there is also an Australian site, but it is mostly for earlier 911`s. I could give you a lead or two.

[Jdub]

I have always loved the 2.7, despite its issues. First off, it is a MAG case, which is very cool, and second, it is a free-revving engine - I'd compare it to the diff between the 230 > 280 MB SL engines where additional support was added to the crankshaft over time. Dependability gained but something lost...

[CountD]

Originally Posted by Reifle

History of the 1974-1977 Porsche 911

The mid 1970s are sort of the forgotten years for Porsche in the U.S. (or at least the years Porsche wishes they could forget). Ever-tightening emission control laws played havoc with engine longevity from 1975 until 1977. Unbelievably, Porsche’s answer to smog regs was heat, thermal reactors burned exhaust gasses and they even removed some fan blades to raise running temperatures. Few 2.7 liter U.S. spec cars made it past 75,000 miles before the engines went kablooey. Experienced Porsche engine builders can fix these issues today, but not if the car still has to pass smog tests. It’s a bit of a moot point anyway as few 1975-77 911s seem to have survived. Other changes included the start of the so-called “short hood” cars which included 5 mph bumpers. Porsche did a far better job integrating these than most other manufacturers. In 1974 and 1975, Porsche offered a 2.7 liter Carrera but it was nothing like the Euro cars. It was mainly fender flares, decals and a rear spoiler. They had the same 160 hp motor as the 911S. Finally, from 1976 on, all 911s got a dip in a zinc galvanizing bath prior to paint. The result was the most rust-resistant 911 yet.

Nice summary, pretty much covers it all.

[javadog]

Originally Posted by CountD

Nice summary, pretty much covers it all.

I don't know about that. Lots of errors in there.

Porsche never wanted the cars to run hotter. The increased oil temperatures seen in 1976 and 1977 were a by-product of the emissions gear used in the US markets. ROW cars didn't have these peoblems.

The 5 blade cooling fan wasn't used to make the engines run hotter. They removed the blades because they intended to spin the cooling fans faster, to allow the alternators to charge more at low revs. The higher speed and fewer blades worked together to give a similar fan output to previous years. Because all 911s could run too hot in some areas of the country, people learned to mix and match the available parts, to run the 11 blade fans using the higher ratios, which gave more cooling air. Cheaper to do this than add an external cooler...

The Carreras were better equipped than he indicated. They had 175hp in 1974 and 165hp in 1975. They also had wider wheels, bigger sway bars and many other details that made them more desirable than the 911S.

Not all of the 2.7 liter cars had the thermal reactors, so not all of them were dead by 75k miles. How he figures that few mid-years have survived is also a bit of a mystery. Porsche wasn't building all that many 911 each year in that era but that was also true of the years prior to that. I'm not aware of any reason why more of the 2.7 cars would have been scrapped.

Anyway, all of the negatives surrounding these cars are irrelevant for someone looking at ROW versions in another country. The original poster may want to steer clear of any stock, US '77 imports, if there are any in his market. Probably not a big concern...

JR

[spuggy]

The '77 MY (which includes some cars built in '76) does have some changes/differences to the 74-76 cars - many (but not all) of them leading on to the SC..

'77 MY saw the end of the last non-galvanised panel on the car - the roof. Frere said they'd been adding galvanised panels for years, by '76 MY only the roof wasn't galvanised. Think Morgan says the factory introduced a 10 year corrosion warranty after this change.

Both the oil temp/pressure gauges are numeric like the 74-76 cars - but the '77 got a 0-340F temp gauge which required a different sensor (same as the 3.2 & all 930's, and NOT the same as the 74-76 and SC sensor, which suits the 0-300F gauge).

'77 MY introduced servo-assisted brakes on both the 911 and the 930, and was the last 911 to use the Type 1 rear swaybar/droplinks (the SC introduced the Type 2). Think it may have been the first year to get the big vent in the center of the dash, although that may have been only cars with factory A/C.

The seat belt/brake warning light used on SC's through '83 was introduced in the '77 MY.

Last year for the optional bright "trim moulding" strip for the wheel arches. Cigarette lighter icon in my '77 looks like an open Zippo, the SC diagram shows the later, "smouldering cigarette" icon.

For '78 MY, the SC lost the numbers on the oil temp guage and went to a 0-5 bar instead of a 0-140 PSI pressure gauge (hence the existence of both 5 bar 10 bar pressure senders), the M/C, calipers and rotors were changed.

The '77 has only 3 levers in the air distribution puzzle in the dash, SC has different part #'s - and later cars certainly had two levers in the top row (for a total of 4), so I'm guessing that change happened then as well.

Last time I looked, it seemed that curb weight for an SC was quoted far higher than the '77 2.7.