need some advice about the 2.7L flat motor
 

Well, I ended up not getting an old Jeep. I added three more parking spaces under one roof so was itching to get something but an old 911 never crossed my mind. Too much money. Got talking with someone and discovered he's off loading a T with a stripped interior. He was building this to be a track car, an RS clone of some sort. He lost interest and never finished. The paint and body is in good shape with SC flares but motor is out. He has a rebuilt 2.7 with Webbers (I am shaking just hearing those numbers) and 915 is in good shape. Suspension is all in. Poly-bronze bushing and big sway bars will kick my ass as a street car. It might be a great deal if it goes through.

I have been reading for the past few days and my head is spinning. Many suggest going to a 3.0 or 3.2 motor and scrap the 2.7 motor. Since the 2.7 is there, he had it rebuilt some time ago (I know this guy well, so I can trust him), what kind of land mine am I going to step into? How reliable are they and what am I up against? I know nothing about these early cars especially their known issues. I believe the motor is stock.

I haven't been at Tech for over 10 years, so I thought I ask here first. Mods please move this to Tech or engine rebuilding if necessary.

Do it!!!

I can hardly breathe I'm so excited.

Do it do it do it....

Easy for you guys to say, but I am scared sihtless just because I know nothing about them. There are lots to learn as I have been reading for hours trying absorb what I can over at Engine Rebuilding section. Seem like the stock engine had some issues even if rebuilt. They leak no matter? Anyone know why so many suggest the 930 valve covers? I should be asking over there, but don't want to highjack their threads for such dumb questions. I have so many.

Think I know one. Change the chain tensioners.

There is nothing wrong with the 2.7 if rebuilt to remove the basic OEM flaws. Install Carrera oil fed tensioners, install new head studs, 930 valve covers, exhaust system with SSIs and trash the thermal reactors, and enjoy.

Exactly - the prevailing "wisdom" out there is that the 2.7 is not worth rebuilding or saving and to just go with a 3.0 or 3.2. I disagree. The 2.7 is a fine engine and can rev very fast. It just needs to be cared for and retrofitted with the Carrera tensioners, check the head studs, ditch the thermal reactors (thank goodness mine never had them), etc. as has been said. Yes, it's a bit more spendy to restore but not terribly more than any other flat six. At the end of the day I'll be glad to have something that's more authentic / period-correct than a bigger "easy way out" behind me. Heck, it's not like our 30+ year old cars are really all that fast anymore by today's standards anyway - even with a 3.2!

However if a 3.2 is your thing - go for it. Do what makes you happy! I'm content with my 2.7.

It depends.... If it was a 5 blade fan, smog motor and had AC it may have troubles. If it is /was a '74 engine, has had head stud work done (time certs installed) they are solid engines and really fun to drive. I should know - I've got one. So, prevailing wisdom is if you're going to need a rebuild and stud work is not yet done, the better bang for the buck is to go with a 3.2. If you want to really build it, the 2.7 get's very expensive, so the 3.2 is a better platform to work from. I'd be curious to know if the p/c's & cams were changed when the carbs went on. If not, then the carbs won't really have much positive effect.

You said it has been rebuilt? what was done to it? If correctly rebuilt (time certs, etc.) 2.7s can be great motors. What year 911 was the motor from?
Are turbo valve covers necessary? My valve covers are the originals and have never leaked a drop.

IMHO there is a LOT of misinformation re: the 2.7L engines, a lot of it from people who have never had one and are just passing on the "conventional wisdom" they have heard. If properly rebuilt, they really present no more issues than any other flat 6..

2.7s from 75-77 were definitely more prone to issues because of the 5 bladed fan and thermal reactors but these issues can be remedied.

Take some time and find out what was done on the rebuild and you can make a much more intelligent decision re: the car and motor. I wouldn't blow it off just because of the 2.7.

I still have my '77 2.7L on the stand in my garage waiting to go into my car when the time is right. You said the engine was rebuilt. See if you can find out what upgrades have been done. The right rebuild yields a very nice engine. It's true you can't just slap a set of Webers on and transform it. It needs a different set of cams & pistons at a minimum. When done right, it has the revvy characteristics of the earlier engines with a bunch more grunt. Mine was done with E cams, Nikysil cylinders, 9.5 J&Es, Carrera tensioners, ARP's, race balanced, Thermal barrier & dry film coatings, & other stuff I don't remember right now. I'm expecting it to run for a long time and make my '69 fun to drive.

911 engines are such an easy swap.

I'd have no problem tossing the 2.7 in, and if it goes belly-up someday, or you just decide you want more grunt, a 3.0 or 3.2 will easily take its place.

Outside of a Volkswagen Beetle, is there an easier engine swap than the 911?

Well, my last 911 was a 76 911S with a 2.7l motor and thermal reactors.
I owned it 19 yrs, had a total engine rebuilt, remove reactors, replace with ssi exhaust, chain tensioners, new head studs and oil cooler in front right wheel well.

Ran awesome, quick and fun for 135k miles, then the ol oil leaking started again, thru the head studs. That is the ding of the motor, the magnesium block with the whatever metal are the head studs heat and cool at different rates so eventually will leak. The aluminum block of the SC's is bombproof

Oh, good I feel a little better. Looks like I need to have a chit chat about the rebuilt. He was going to go racing with that engine, so I cam only assume all bugs had been worked out.

Marv, What's a thermal barrier and dry film coating?

Jeff, I built a 2.7RS-spec engine with help from Competition Engineering and a fellow Pelican for my old 73E. Great engine, rev-happy, and moved the car nicely on the track. Like others have said, try to find out what work was done to it.

So, are you building a fleet of P-cars? When are the 959 and 918 arriving? ;)

Hey Jim,

Those two will arrive at the same time you get out here:D. Come and think of it, you guys should be any day now?

I added a three car garage on my rental and need to keep that occupy before my wife gets wind of it. It can be packed with her junk, real fast! She can't seem to have enough craft stuff for the kids and their school. She doesn't know about the garages yet, but I have been hinting the built for the past couple years. One of the garage is 14" tall, 16' wide X 20' deep. You see my plan? Lift install maybe next to do a little fussing when needed. I haven't done any work on cars in a very long time. This maybe my semiretirement sanity. I am started to sound like your neighbor, Gill. I think that's his name?

This little 911 just fell on my lap. He lost interest in P cars about 10 years ago, and has been running his private team in races like the Baja 500 and other off road type racing. All his road cars has been sitting on the side line for about 5-10 years now. I know him very well, we ride our bicycles weekly so I am not concern about the quality of the built and he's a solid guy ( I bought the 993 TT from him also a couple of years ago). My only problem is that he doesn't always know or remember what's been done to his motors or what he has around. I just need to learn about these early cars now. That's part of the fun.

Competition Engineering in Lake Isabella or Bodfish, CA? I might call you and pick your brain about the build once you get out here in paradise.

Jeff

Lets just assume some of the mandatory items did not get changed out during the rebuilt. With the motor out, how difficult to get the tensioner changed out or a cam installed? I am sure its been done knowing my friend, but that's doesn't sound like its too time consuming to do? I have never opened up a 911 motor.

Tensioners easy. Cam's not too hard, but pointless unless you do pistons and cylinders too - that's a top end teardown. Probably not a good first time project unless you have experienced help nearby. Find out what's already been done before you get too excited or start spending money.

Compression needs to be in the 9s and not 8 for an effect cam for the extra gain in hp?

Valve clearance. Depending on what cam - if pistons are stock the valves can hit pistons. Very not good.

I'm biased because I really like the 3.2 case, which is very strong. But, even if you have the wiring harness, tranny and clutch, etc worked out then a rebuild could easily double the costs you have in the car. So that's the logic behind rebuilding what you have.