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2teeners
Which engines are the best 6 cylinders. It seems I read somewhere that mid 70's models were lacking in durability. What was it and is there a fix now? And as far as value, which would be the best.

Paul ohmy.gif
krk
This post of mine will be of limited value. (this is, of course, in sharp contrast with my other posts:) Bruce Anderson's 911 book is a great reference for the various generations of P-6's, including strengths, weaknesses, fixes for weaknesses, etc. Lots of grotty details. Borrow or buy one.

Actual choice will depend on what you want to do and your budget (duh). Popular choice these days seems to be the 3.2, but Brad and others will chime in with real data. I've never done a conversion, so I'm just parroting info I've picked up from others.

kim.
mskala
From reading Bruce's book and from seeing posts on various boards, it seems to me like every variant has known problems, minor on some years, major on others. But people have figured out the fixes for them and there is decades of history for proof. If you are going to have an engine to put in a 914, you can fix the problems before you put it in. Then you can worry about other things.
Mark S.
'70 914-6 known problem is lack of power smile.gif
Gint
Brad will correct me if necessary, but I believe the main complaint about the mid 70's years motors (2.7 and such), were the fact that they were smogged and catalytic converter'd to death (slow constant heat).
J P Stein
This question doesn't have an easy answer.
Much depends of what you are gonna do with the car......and, of course, how much treasure you can steal form the family budget.

In my case, the original conversion cost about $6600 of which $2400 went towards the motor ...a solid 2.4L T...130/140 hp. All the parts were new, cept the motor, and you can see that it was less than half the budget.

When one steps over the 170hp mark, an external cooler is a good idea......Brad doesn't agree with that, but WHF does he know? blink.gif Tack on bout 800/1000 for a good set up there.

To keep this short, if I had it to do again, I would go with a carbed, but otherwise stock 3.0L..... 200 hp or so, with room for growth. Budget here would be 4500/6000. If you're not into "growth" stick with CIS and save 1500 or so.
Brad Roberts
Here is how I approach this:

Nothing under a 3.0. Simple.

You will see core engines (2.0-2.7) for cheap.. there is a reason. For what it would cost you to rebuild a 2.0-2.7 you could have bought a low mileage 3.0-3.2. I feel JP's case was pretty rare. He found a decent engine with good parts (under 3.0) I have access to a running 3.0 engine right now for 1500$ Complete. It has 80k miles on it and 2 broken head studs. I would pull it apart and fix the studs/re-ring it (maybe 800$ with gaskets and such)

You really should buy the Bruce Anderson book. Dont buy or even look at a 6cyl engine for your car until you read this book.

B
campbellcj
I agree with what you guys are saying re. the 3.0-3.2 engines as the "sweet spot".

Unless you are doing track stuff, and that puts you into a classification with guys spending $50K-100K on their cars and you are on a "budget".

In that case the 2.0-2.7 sizing (depending what fits in your class and what you have access to) starts to look pretty darn good.

For a street conversion, no question, go with a strong 3.0 or 3.2 injected donor and don't look back. You will have the bulletproof motor of the 80's 911's with about 800lbs less car to haul around.
thesey914
Did a search for the Bruce Anderson book and got "Tantra For Gay Men" as a result!!!! Guess it's a different author by the same name biggrin.gif
Do you recommend this book ( not the gay tantric one!!) as an engine rebuild manual or is it more tailored for the 911 buyer?
I am looking at a couple of 911 motors but they will most likely need a bit of refreshing so a bit of reference literature will be a great help
Brad Roberts
Umm.. I used Google and it came up number 2 on the list.

http://www.911handbook.com/

Bruces book('s) has the best 911 engine coverage of any book. It does have 911 body styles and changes.. but its 80% engine/tranny/suspension which all fits under you 914 (except the rear suspension). You cant go wrong. If you order it from Bruce.. tell him Brad Roberts sent you. I consider us pretty good friends.

Oh.. it is not a rebuild book. Bruce and Jerry Woods teach a engine rebuild class. I doubt they will write a book about it. What Bruces book will do: It will tell you exactly what to look for in an engine...and what the issues where along with engine codes.

B
J P Stein
The only problem with a 3.0L+ motor is if you wanna go play at the SCCA autocrosses. What class are you in?....got me.
F prepared is limited to 2.8L with a 914.

Now if I could find a 3.0L 76/77 Carrera or 75/77 (?) 3.0 turbo case, I would build a new motor.....cheep,too....well, relativly.
I gots a plan. blink.gif

Andersons book is (or should be ) required reading for anyone considering a 911 engine purchase. I've read it cover to cover ....more than once.
Jeroen
Hey JP,

That's just what I got: a 3.0 Carrera engine biggrin.gif
It's still missing the crank and cams though
(it's still apart) but the heads have been rebuild

If I'm not mistaking the crank of my 2.4 should fit/be the same
Still have to check what cams are on my 2.4 to now if they'll work with the 3.0 and webbers

Cheers,

Jeroen
J P Stein
Jeroen [/QUOTE]
>If I'm not mistaking the crank of my 2.4 should fit/be the >same

If I'm not mistaking, you're right tongue.gif
Jeroen
Hey JP,

I guess we have a common goal biggrin.gif

Cheers,

Jeroen
thesey914
Just received Bruce Anderson's book through the post this morning. Looks very detailed....well recommended, thanks.
seanery
thesey914,

I like your avatar, very nice!
thesey914
Thanks beerchug.gif
Brad Roberts
I didnt realize you are located in the UK.

Your avatar is cool.. but something is missing (its not on a car) lol

B
Crawf
Hello,

Another fourteener from the UK here, I thought I'd take the opportunity to drop an e-mail to say what a useful website this is. I'm sure I'll be posting a few questions shortly.

The Sey - I didn't know you were contemplating a six conversion, did you source the Bruce Anderson book locally?

Crawf
Dave_Darling
All B's points are true--but still, I like the idea of the earlier motor in the 914. The 2.4 "S" motor, to me, seems a terriffic choice. (Maybe carb'ed for simplicity over MFI.)

The early motors are lighter, and the swap is a little simpler. (Mostly the fact that you use an early 911 flywheel, instead of a more-expensive "converting" flywheel like on the 3.0+ cars.) And using a 70's-vintage motor in the 70's-vintage 914 seems "right" somehow.

Then again, if it were me I might just jump to 3.2 liters and run the stock Motronic FI. That way I wouldn't have to deal with those "black magic" carburetor thingies. wink.gif

--DD
campbellcj
QUOTE(Dave_Darling @ Jan 21 2003, 03:16 PM)
All B's points are true--but still, I like the idea of the earlier motor in the 914. The 2.4 "S" motor, to me, seems a terriffic choice. (Maybe carb'ed for simplicity over MFI.)

Dave - I have to admit that the moment I decided I HAD to get a sixer was the first time I hitched a ride at the track in a well-prepped factory -6 with a 2.4S engine. I think the car was carbed and running open pipes or maybe supertrapps. It seemed like a great match with the narrowbody car on Hoosiers. I fell in love instantly.
mightyohm
I've heard it's not possible to adjust MFI while the engine is in the car. Is that true? I imagine getting to the idle mixture adjuster is probably the one that can't be done since traditionally you access that through the fan blades, but part load should be fine (allen wrench). Synchronizing the intakes/adjusting the linkages would also be a pain in that limited space. Keep that in mind with the early motors.
Adjusting MFI is hard enough on a 911. BTDT.
J P Stein
Howza' bout if you had one of these to get at the fan?
914Timo
JP, if you like to have 3.0L 76/77 Carrera 930/02 case, I know one here in Finland. It is empty block and the owner is asking about 650 euros (about $700). The postage would be about $100. Let me know if you are interested in about it. wavey.gif

I think $800 is too much. Of course I could ask "the price of the day", but I donĀ“t believe the owner will ever sell it under 500 euros. ar15.gif

He has a set of titanium connecting rods too asking 2500 euros per set !!!!
Brad Roberts
Timo,

I may want that case. Short stroke 9k RPM 3.2

B
mightyohm
JP, that would work. biggrin.gif
Brad Roberts
My hole is bigger (is that right ??)
ChrisReale
You guys are clever sonsaguns ar15.gif I kinda want a six to play with now sad.gif
seanery
Hey,

Don't the factory firewalls have to remain intact somewhat for PCA?

Brad's doesn't look at all intact.
J P Stein
QUOTE(Brad Roberts @ Jan 22 2003, 10:20 AM)
My hole is bigger (is that right ??)

Fer sure, Brad, your hole is MUCH bigger biggrin.gif
SirAndy
brads car never HAD a real firewall :-)
it's not even a 914 ...
started it's life on a jig.

i'm not sure if it is PCA legal. brad ???
Brad Roberts
Nothing on the car is PCA legal..ha ha I can run it in GTP class in PCA, but I'm against 962's and the such.

Andy is correct. The race car is not a 914. 99% of what you see is fiberglass. The rear tail light section is 914 as well as the windshield hoop. Targa bar is FG.

B
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