76 widebody project

[avt007]

Hi guys,

I just picked up a project car for my son (Andrew, 15) and I to work on together.
Here's the details-
1. 1976 911S, with a steel widebody kit. pretty decent shape.
2. 2.7 engine (7R case), partially disassembled, all the studs are there, but one, and the the threads in the case look nice. It appears to have an insert in it, but I'm not familiar with these engines. The story is, the engine lost oil pressure. So far, I haven't seen any damage in the heads, and the next step is to pull a con rod off and check the crank. The case is still together, with a couple cylinders removed.
3. It has S brakes, rebuilt, aluminum 4 piston jobs, with ventilated and drilled rotors.
4. the interior is nice, but I need a tach, and a speedo, and a windshield.
5. There is no exhaust.
6. The wheels are true 3 piece rims, CSI brand? with 245 rears and 195 fronts, 16"
7. As mentioned in another thread, the transmission is apparently from a 78 SC, but I don't know if it was ever installed in this car. So I don't know if the shifter will fit, plus I'm missing the axles and CV joints. Does any of this sound familiar? I'm sure I'm not the only guy to buy a car in kit form. Good thing I already have grey hair,eh?
It should be an adventure, so stand by for endless questions, parts requests, and progress reports. Luckily I have my 86 911 for comparison purposes. A lot of the parts are in boxes, so it's like Christmas, except I don't know where some of the bits go!
Rob

[Cdnone1]

Wow
I wish I had a Dad like you when I was growing up!

Steve

[WOLVERINE]

Suscribed,from just across the border............

[avt007]

Just to clarify, I am not a fool, I am not giving my son a 911 for his first car. The (hoped for) profits from this venture will go towards getting him his first car. Something slower and much less interesting, I'm sure.

[poorsha]

Subscribed.

[avt007]

So here's the first question- what did I just buy, engine-wise? An expensive paperweight? A rare and priceless jewel? A middle of the road 2.7? Any opinions are appreciated.

[avt007]

And more-

[gsmith660]

I think you got a run of the mill 2.7 /w mahle pistons thats a plus 2.7's get a bad rap but if you do certain things to them you can nearly make them bulletproof some are casesavers and new improved head studs, pressure fed tensioners. Do a search and all the improvements can be found.

[sww914]

Those are RS pistons, designed for 9.5:1 compression up from 8.5:1. They'll give you more room for cams that the stock CIS pistons and with something like S cams, modS cams or maybe GE40 or DC40 cams and carbs or MFI or EFI you'll have a really fun motor. You have the case with a 7R suffix, it's the strongest magnesium case that they made at least for street cars, that's good. The 2.7's are widely known for pulling the head studs out of the case. The case must be Timecerted or case savered in the head stud holes if it hasn't already been done. The 2.7 was the largest street motor built from the magnesium case and it was the first of the smog years so to lower emissions Porsche added a 5 bladed fan which increased operating temperatures and added thermal reactors to the exhaust which increased cylinder and head temperatures, all of which made the cylinders expand a great deal more than the steel head studs, causing them to eventually pull the studs out of the case. Your head studs should also be replaced with either Dilivar, the 993 fully threaded Dilavar, or the Supertec head studs or maybe ARP or Raceware. Head studs are somewhat of a religion and as far as I know religious discussions are specifically prohibited in the rules so I will refrain from stating my beliefs. If you search the engine rebuilding forum you will learn plenty.
You need to buy 2 books. Bruce Anderson's Porsche 911 performance handbook and Wayne Dempsey's book (he owns this place). I got mine used on ebay and amazon for about $13.00 each. Money well spent even if I never built an engine, which I have.

[sww914]

BTW the S trannies and the SC trannies interchange as well as the shifters. They're all 915's.

[notmytarga]

I looks like you included enough Kokanee Beer to tempt a few Pelicans to drop by for an on-site evaluation. Take it all down and build it back up right. If there are head stud inserts they will be metallic - test them once you remove the studs. Those are Nikasil cylinders - if they are more reusable than Alusil, if they are not "ovalized". A good machinist will go over all the parts with the specifications book and tell you what is worn beyond reuse.

If you don't have Waynes rebuild book - get it - any decisions are also discussed here already and can be found by searching.

Enjoy the project with your son. My engine blew (dropped valve 1975 S Targa) ahead of 'schedule' - I was hoping my now 5 year old would be able to participate in the rebuild whn he was 'of age'. Instead I was careful that he didn't scramble the parts and instead had my teen daughters help with a few steps, photos and scribe work.

[relayswitcher]

20 things I can tell you to do.

Don't know your expertise so don't be offended if I state things as if you don't already know them.
1. 75% of the 2.7Litre engines did not last much past 50-70k miles Why?
2. ... because the case over heated from a smog attachmt. called a "thermal reactor" like a catalytic converter placed directly underneath the heads (3 each side). This severe heating caused the head studs to pull away from the case (especially the lower 12) .... thus the heads pull away from the barrels leak air, lose compression, and you hear what sounds like an exhaust leak. Then after lots of $$ spent on trying to fix the exhaust, a Porsche human will let you know that it is the heads banging on the barrels causing "head shatter" and not exhaust leaking noises.
3. Depending on your engine miles you will HAVE TO rebuild the engine from the barrels out, BUT why trust everything is okay, you don't know this engine really, do you? I'd just open the case (3-4 hours more) and place new main and rod bearings and the 2 bearings for the intermediate shaft that turns your oil pump off the crankshaft. Having done that, you are 70% done with a completely new rebuild.
4. To remedy not hearing head shatter again, have a MACHINE SHOP specializing in Porsche install "COURSE THREAD" steel inserts into your existing head stud holes. They are course for grabbing more of the meat metal of the engine block and 3 times as hard to pull ( they usually never pull again after this is done.)
5. I and some others are of the belief of leaving things the way the factory designed it in Germany. My advice to you is use the factory head studs... unless you want to spend gobs more money on fancy studs that I've seen break anyway. Unless you are a pro racer or semi pro... you don't need them.
6. Have all six heads rebuilt completely so you have no worries and who ever you sell the car to will have your paper work of what was done..... thus more cash value for your car.
7. Buy a complete rebuilding gasket set.
8. New #8 bearing. Rod bearings and mains, and head gaskets... do not reuse old ones.... they are one time crimp downs.
9 Have your crackshaft taken to any reputable crank place to check for true and if it needs to be reground. ***Sometimes it's cheaper to buy a good USED crank instead of having to pay for grind and then paying for oversized 10s which can run 3-$400. A good used crank will only be about $30 for a micro polish. Again, it doesn't have to be a Porsche crank place.... MMs are MMs in any book.
Although, there is a method of having the crank "cross drilled " so the bearings get more oil to them. You do know that bearings on a crank really never do touch the crank as much as they are floating or as like to say, hydroplaning on the oil.
10. Have the squirters on you cam towers removed and cleaned out.
11. Have your oil cooler flushed out.
12. Have your fuel injection lines cleaned out.
13. Place a "pop off toilet seat" anti-backfire valve installed in your injection airbox.
14. Replace all the little low cost senders ....especially the rear oil temp sender that is next to impossible to replace with engine in the car.
15. Throw away those "thermal reactors".... they are about the size of a box of donuts and about as long. ( Of course this all depends on your smog guilt or if you need a pump at all.) I used to smog and then remove when I had this engine in my '76 911S Targa.
16. To secure some COOL for the engine place a secondary front right wheel weld oil cooler.
17. Don't go carbs on this.... it was made for CIS injection. "Continuous Injection System".
18. Use collapsible oil return tubes.
19. Use 20-50 Valveline high rev oil.
20. Remember that Porsches use on average 1 full qt. of oil per 1000 miles. It's true, but will vary some. CHeck and check and check your oil..... don't learn the hard way.

Short of building the engine for you, I'm happy to help with questions you need answered when I am home anyway. Or you can fly me up for a week and pay me....LOL. Just kidding..... although, I've never been to BC. I have been to France so close enough I guess. LOL.

Amigos, JOSH / RelaySwitcher PHotos below.

The larger course insert: See the bigger courser thread in comparison to the factory male thread on the stud here that is the same in the factory drilled ones in the case.... too, fine a thread for the heat and softness of the case.


How the course thread looks inserted... the course thread has the factory size thread inside.... I'm sure you understood that.


Picture of Pop Off valve... about $40--60. Saves you airbox from blowing up in a million pieces or just cracks.

[crustychief]

HAHA NOTMYTARGA! I was thinking is this guy on Kokanee? avt007, that is a nice looking car for a first project!! I have three sons 18,16 and 13. I wish the oldest and I had a little easier life during his earlier teens ( divorce ) and the middle guy is totally wrapped up in music ( plays tuba for the Mira Mesa High band
http://www.youtube.com/watch?v=Td0kiP8gSDM
I am very proud of him, but not a lot of time for projects. My youngest is gonna be a gearhead with a little training. he used to race motorcycles and was really good at it and he will do anything to "run the machine" We are getting into RC planes now. I have been flying them since the early 80s but got him one at a friends garage sale and can't wait to take it out. Good luck with your project. Have the boy check out the pedal set, an easy first with a rebuild kit from our host.

[avt007]

Here's what one hole looks like. To me, it looks like an insert has already been installed.
Other details- yes, it has a popoff valve, and I have the CIS for the car. Gotta run, more details later.

[avt007]

Wow, lots of feeedback, that's great. I'll try to answer in order.
gmsmioth thanks for the info. It does not have Carrera tensioners at this point.
SWW, is there any way to identify the cams I have, the numbers stamped on the ends are 91114100 and 91114200. The pistons are good news, as are the barrels. The fan is 11 bladed. Is there a way to identify what studs have been installed?
Notmytarga- Kokanee is "The beer out here"! Sadly those in the pictures are all empty. What you can't see is the beer fridge (along with the mandatory "911 parking only" sign), stocked with more Kokanee and Canadian.
The insert in the picture is metallic so I guess that's more good news.
Relayswitcher (are you in aviation? cool username,either way) there are no thermal reactors on the car, nor will there be. I intend to split the cases and see what the crank is like, it will help decide whether to rebuild this, or replace it with a 3.0. After that the heads will get a good inspection to see where I'm at. The thing here is that it doesn't make sense to me to sink mega dollars into a 2.7 (since this is not going to be a collector car, or original in any way)
if I can dropa 3.0 in for a lot less money and hassle. On the other hand, I'd like to rebuild a Porsche. I've done engines from 2 strokes to a big block, but not one of these. It's the price that scares me away, frankly. So for now it's a teardown and postmortem to see what I'm looking at to get her on the road again. I'd like to avoid sinking 25k into a 15k car.
Crustychief- good idea on the pedals. My son is car crazy. This car will teach him a lot, from tools to theory to mechanics, physics, and probably a couple new swear words along the way. He'll also learn the joys of skinned knuckles, dirt in the eye, and the taste of oily sludge.
Ahh. good times!

[gsmith660]

On the studs if they are non magnetic then they are dilivar studs otherwise they could be your guess is as good as mine. if you go 3.0 might as well go 3.2

[gsmith660]

You know I need to look at my spare set of P&C's they might be the same the number looks familiar.

[avt007]

The upper studs are magnetic. The lower ones are not, and have black paint on them, and almost brass sort of colour on the threads.

[Flieger]

That was the factory spec stud installation for those years of naturally aspirated cars.

Steel upper head studs, Dilavar lower.

Porsche said it was because the lower got hotter next to the exhaust and expanded more than the top next to the cooling fan. To even it out the clamping force, they used steel top, Dilavar lower.

I think they were experimenting.

I would use 993 Dilavar studs all around.

[Bill Verburg]

Thats a standard '76 Mahle Nikasil cyl,
6 in the triangle is the height group 85.425 - 85.450mm
0 is the cyl. bore group 90.000 - 90.010mm

the pistons look like std 8.5 forged Mahle 2.7 for nikisil cyls used in the 911 and 911S in '76

the numbers stamped on the ends are 91114100 and 91114200

std 2.7 cams used for 911/911S in '76

the heads appear to be std '76 fare, w/ 35/35 mm ports