Which /6 motor is cheaper to rebuild? 2.7L or the 3.0L?

1. Assume core motor is in good condtion and no crazy findings when you tear it down.
2. Assume you are building the motor for longevity
3. You are putting this in a 914/6 conversion (was /4)

3.0L
The Aluminum case of the 3.0L won't kill your whole project budget at the machine shop, the mag case of a 2.7L might.

Jim

I'd say about the same, but there's so many variables. No two rebuilds are the same.
Even if you think 2 cores may be in equil shape, you have no idea till you get in there.
One to keep in mind is, not counting the price of the core, it will ballpark cost you just as much to rebuild a 2.0 as a 3.6

Personally I have a 3.0 and a 2.7, both in pretty good shape with inspected good std/std cranks. For now I'm keeping the 2.7 as a just in case back-up core.
I built the 3.0

What's a good price these days for a 2.7L vs 3.0L core for rebuild?

I'm finding the 2.7L motors about $3-4K cheaper....

Lots of pro's and cons
2.7 Pro's
Magnesium case = lighter
Can use early 914-6/911 2.0 flywheel and stock 914-4 2.0 clutch. Clutch feels just like a stock 914-4 2.0
2.7 Cons
Case is weaker. check out Bruce Anderson 911 performance hand book. Might need case savers, timeserts and special head studs. I used to have a 2.7 and when it started to pull head studs, i sold it and bought a used 3.2 from a wrecking yard.
Cheaper than overhauling the 2.7. 3.2 stock injection is really nice, but I wasn't happy with the 914-4 gearing and ended up spending big bucks for a 916 gear box.
3.0 pro's
Case is much stronger and doesn't require the above
Known as the most reliable 911 motor
3.0 cons
Heavier
Requires special adapter flywheel to be used with 901/914 trans, unless you convert your 914 gearbox to a pull type clutch. I was not a fan of the special KEP bus clutch adapter flywheel. Harder to push compared to stock

My advice is think about your end goal before plunking tons of money down. Try to drive both. Get multiple estimates to rebuild both correctly

without a doubt.

I am doing a 2.7 because I got a screaming good deal on it (Thanks again, Thomas - Tschrifield). If you don't already have case-savers for your head studs, they are a must and will set you back hundreds that you wouldn't have to spend on an aluminum case. I would also rather have an aluminum case for longevity and strength.

The good thing about 2.7s is that cores tend to be cheaper, so this may offset your machining costs. If you aren't shooting for 250 hp, I wouldn't rule them out if you find a good deal.

unless money is no object, don't stretch your budget too thin. there is nothing wrong with a great running 2.0 four. a six will be faster, if you don't mind speeding tickets. don't overlook the benefits of tight: suspension, brakes, steering, etc. when it comes to joy to drive.

Yeah, that seems to be the rub. When there is thousands price difference between them it starts to get attractive. I'm really not aiming for mega-horsepower. Anywhere near 200HP will be fine for this street car. That's quite an upgrade anyway from the stock 2.0L.

None of the above...

Budget five figures to rebuild either one.

--DD

a totally tight car with 115-125 hp would be plenty enjoyable and cost a shit load less. just saying. what is the status of your car at this moment?

If you don't already have Wayne Dempsey's 911 rebuilding book, you should get a copy. Lots of great information in there about engine combinations that work and their resulting characteristics. And Bruce Anderson's 911 Performance Handbook is like drinking from a fire hose.

I am also shooting for somewhere around 200 hp. My current plan is to ditch the CIS, 9.5:1 JE pistons, S (ish) Crane cams (another deal from Thomas), and probably Megasquirt for induction.

I got very lucky with my motor. When I tore it apart, it appears to have a pretty fresh rebuild, and it already had Nicasil cylinders (can still see the factory cross-hatching!!!) and case savers or time-serts (can't tell which). I could probably clean it up and put it back together without even replacing the bearings, but I want to build a nice tight engine.

If you aren't in a hurry, do the research to help you decide what you want to end up with, and then just wait/watch for good deals on the components that will get you there. Best of luck!

Car is still half apart in the garage. Motor is still in it.

I'm kicking the tires here a little bit. My intentions had been to have a 2270 built with ITB's and megasquirt setup.

Just like our cars, buy the best one you can. The more you have to replace, modify, upgrade, repair, ect, the more it will cost compared to buying a good running engine.

Stock 3.2's actually make around 207-210. The smaller motors make considerably less unless they're an S motor with mfi.

Wise advice. What's your budget? Unlimited, go 3.6

QUOTE O.P: "Anywhere near 200HP will be fine for this street car."


a stock 3.2 with Motronic-DME will give you 205-217 hp - with no more drama to install in your conversion project than any other -6 choice

getting 200hp out of a 2.7 or smaller is not an average nor cheap build - (BTDT - a 2.8 on a 2.4, and a 2.7RS on a new case)

the advice from the guys above is spot-on

the "cheapest' trick is to find a decent complete 3.2 without big miles on it - but that's mostly a "barn find" dream

(a few yrs ago PMS told me they'd quit doing 3.2 conversions cuz they could not find any decent ones that didn't need a rebuild)

if you find a 3.2 needing top end work (highly likely on any older 3.2), be aware that the bottom ends will go 250K easy, so you may avoid a complete teardown)

fwiw last year i sold a 3.2 with 188K miles on it, needing a valve job, with all the injection, etc; but no alt-fan & no DME or harness - i advertised it at $5500 on Craigs and had 6 guys panting for it in one day - a guy came all the way from LA for it with cash in hand (a DME & harness is another grand, alt-fan another $600) - (i previously advert it here on world for $7500 COMPLETE with no takers, so i decided it was worth more parted out & stripped it to long block, sold the FW, clutch & various other parts - got more than my original ask in the end)

best -shop for a whole wrecked Carrera & hope for one with acceptable miles on it or some verifiable evidence of prior work - just have your checkbook ready

I lucked out!!! Back in 2000 a wrecking yard up north was trying to sell a 1984 gray market 911. They finally gave up and parted it out. I bought the motor. It's a 231 hp euro 3.2. Runs great!! I paid $5200 for it and sold the exhaust and extra parts for around $500

Just to keep it honest....
Unless you have horseshoes up your ass, you're not likely to be finding any 3.2 for $5-6K these days.

Not a 3.2 but a twin plug 3.0 mfi for $4k, well, yes...
(Needs a top end)

Is that what you found? I thought a 3.0 would be CIS?
I know some guys get lucky and some guys can wait till they get lucky, but it's not the norm.

This is a modified motor. I would have paid the money if it was a core.

Yep!!
LA Dismantlers gets $8k-$10k for a 3.2 depending on mileage.

I once heard the saying - the deal of a lifetime comes around once a month. I totally believe it.

That's if you buy retail.

EXCEPT- DO NOT put silicone on the case thru bolts!!! He calls that out in his rebuild book. Made me seal my case up twice! Look up on the pelican forums (ironically), the proper way is to use some sort of special lubricant.

Other than that his book rocks!!!!

Headstuds worry me on a used 3.2, that's why I choose to rebuild my 3.0. But if you didnt have a motor, purchasing a 3.2, replacing the headstuds, valvejob and re-sealing the topend is not a bad route to go. Shouldn't cost too much for the top-end rebuild.

I've never heard of a head stud problem with a 3.2. There are rare cases of valve guides and rod bolt problems. My motor has at least 150k miles on it and it's never been opened. Still has good compression, doesn't smoke or leak.
Interesting... I just googled it and broken head studs are showing up on high mileage 3.2 motors. Ah well... Nothing lasts forever except maybe the earth and sky!! lol

Jim I think to OP is looking @ around 165 - 180 hp which ever motor he buys,again the cost to do this a 4 cyl is really up there cause you have to spend the extra to keep it reliable.
The cost involved in making the 2.7 more reliable is well documented,the 5 blade fan motors had big case issues for example due to overheating.
Both motors are rather lazy in there power output due to the CIS,many report good gains just going to well set-up carbs....then economy is an issue however.
The 3.0 is my choice because they are very reliable,make sure you buy a motor that is the most you can pay and a proven runner to start with.
You are going to spend a lot of money because its not just buying the motor ,but when you look at the original sixes now beyond any average guys budget the good conversions will hold and improve resale prices as time goes on.

for 165-180 hp is a n/a subaru motor the most cost effective choice? Assuming the original poster was interested.

Can you mount the radiator above the motor like the VW guys do? has anyone done that in a 914?

To answer the original question (2.7 vs 3.0) for cost, read wayne's book he adds up the machining cost on a 2.7 it is quite substantial. I used to have a 2.7 and elected to jump to the 3.0 case for this reason.

Sorry to be the bearer of bad news... I think on the bright side if you keep your car inside most of the time they are suppose to last longer.

I have a supposedly decent 2.7 core...I'll need to do a leak-down test to see if it's worth messing with. It has all the signs of the PO's story of a rebuild. Came out of a '77, but is a '74 case with oil tensioners, 11 blade fan, 930 valve covers etc.

Even saying that, I'd probably like to start with a 3.0 case if I could get one for the same $...and a 3.2 for sure if I could find a good one for ~$8k.

Here's the rub, and my .03 of thoughts, should you even be willing to pay that much for it, as I consider myself a 914 noob, and all this may be irrelevant... Obviously you've been around here much longer.

Plenty of good advice here, I'm sure. Your OP was a question about rebuild costs for a 6, so that's obviously what you're considering. I doubt there's many here who haven't thought of dropping a six in their car. Very sexy, and nothing sounds like one
But now while your car is half apart is a good time to do a little tasting.

So... I've got a friend who decided to drop a six into his 914, and had a shop rebuild the 2.0 core he bought to slightly larger specs. I don't know what power he was able to attain ultimately, but the money he spent would blow your mind. Granted, the shop did all the work, soup to nuts, but it was nuts indeed. Fortunately he has the resources to do such a thing. He's happy with it. I drove that car.

I have another friend who had his 4 rebuilt to a 2270 by a very reputable shop. Not certain what the exact power result was, probably around 150. The money he spent was right in line with a performance 4 build. He's happy with it. I drove that car too.

Another friend found a real good deal on a six and did a very nice conversion in a short time for very low dollars, but I'm gathering he's the exception. Unfortunately, I haven't driven that car

Lastly, the 75 911 I had (which Mr. Anderson stated was the least desirable one in his buyer's guide, who knew) with it's 2.7 rated at 157hp from the factory, threw that car around very nicely. So nice in fact, I was able to pull real good like on my BIL's stock Vette down Las Virgenes one night in 2nd gear. (That was his last of some twenty Corvettes, he later bought a 930 but that's a whole 'nother story.) We both wound up with moving violations within a week of each other, albeit for different reasons. I drove that car cross country, had it for a few more years, and it was completely reliable.

My own car went from a 2.0 to a 2056. It's a nice, noticeable difference.

Hmmm, pushrods. Hmmm, overhead cams...

Ok, what's my point? Probably the best thing you can do now is to try to get a little seat time in with cars that feature your possible choice. Everyone is different, so there's lots of variables. Unfortunately, budgets limit most of us. Then, of course, there's the slippery slope quotient so often mentioned here, which also needs to be factored in.

I know what I would pick. Whatever you decide, it's still gonna be fun.

That's exactly my focus right now for my resto-car, although it's going to be long enough before I'm ready that my focus could change. Are you NOT interested in going 2270/ITBs/Megasquirt now and did something change your mind? I suppose with the money and effort required regardless of the selection it's natural to want 200 hp rather than ~140/150...

Head studs are a common issue on the high milage 3.0-3.2, but unlike the mag cases that pull the stud out of the case, the dilvalar (sp?) studs are known to just snap.
Good news is it is most times an easy fix during a top end job.
3.0 have stronger rods, the 3.2 has been known on occasion to throw a rod.
Valve guides are not rare what so ever and must be serviced/replaced during a top end service.

The 3.2 is a real good engine and has a excellent FI system, but never be sucked into the complacency of thinking it's a perfect, bullet proof engine.
All versions of the /6 engines have strengths and weaknesses.

That seems to be an important aspect. The motor itself starts cheaper by quite a bit because of the factors listed here. In 1976, you would have had quite the thing with a 2.7 in the 914.

We were putting a 3.2 on an engine stand one day and a head stud snapped and it shot up 2 feet and fell on the floor. No one had touched the stud and none of the others had broken. It was getting a rebuild anyway but still....

We just rebuilt a 3.6, 2 days ago with 4 broken head studs.

Built properly, a 2,7L is a decent motor. MY old 2.7L had 205hp at the wheels.
I built it in 2000 then refreshened it 2007( and added 10:1 Mahles......got a NOS set for half price.....still not cheap). It was strictly an AX motor and spent a good part of its life bouncing off the rev limiter. (7200-7300 rpm depending. Try that with a T-4.)

I sold the car in 2011 (IIRC) and the motor was at the top of it's game. The new owner sold the engine for $8K. That said, the 3.0 L is a better motor.....with the 2.7 you have to be good......and lucky. We had 1 DNF in 12 years of Axing.......an electrical fault.

The days of an inexpensive 6 into a 914 swap are over. Pick your poison.

T-4 are shit, unreliable, and have no grunt, even when compared with a mag case 6.

No surprise, stick a magnet on it, I bet it doesn't stick. Dilavar

Dilavar studs are used on the aluminum cylinders.

So on head studs you could replace with OE steel studs $250/24 or aftermarket studs from $500 to $640/24 or new dilavar studs at over $1100/24
Funny the bird say 24pcs but IIRC only the bottom studs are dilavar.

Big debates on which of the aftermarkets are better, some purists still say the dilators are the best even with the issues.
One thing is you can't do twin plug with the factory barrel nuts.
I personally have used the ARP and wasn't overly impressed, I used Supertec studs on my 3.0 build.

Please educate me, my 3.2 has twin plugs?

That is performance build right?

I'm not sure but maybe a 12mm plug can sneak in there, no way on a full size plug. I prefer the full size plug then all the plugs are the same.
You might be able to use a different nut, never really checked into it.

BTW I offer twin plug service on 3.0-3.6 heads and I never break fins

I'd also ask yourself what kind of motor do you want? A proper (right cams, timing, etc...) carbed motor is a different animal than fuel injected motor, imho.

I ran a webber carbed/cammed 3.0L for years (now rebuilt into a 3.2L), it was a blast of a motor. Good power/weight with the 914, sound was amazing too. Very reliable for me, seems like most sixes that don't have an old un-maintained CIS system are reliable. I drag raced a modern 6.0 GTO at laguna seca down the main straight and we were neck and neck.

Fuel injection would add mpg, smoothness and cleaner air. This is because the old IDA webber design requires a fuel mixture of around 12:1 at cruise to keep the idle circuits to operate smooth.

i'd sure like to see someone else do a mcmark style turbo 4.

http://www.914world.com/bbs2/index.php?sho...54&hl=turbo

Not to be a dink but this is a discussion on the six.

The other side of this coin is what kind of motor are you getting?

I've seen some real abortion builds out there....

i hear you.

but i see it as a 175-200 hp thread, selective reading i guess

i am driving one of those abortions you are reffering too and i know it.

Sounds like someone did some work on it, see if you can find evidence of time certs on the head studs. Someone told me that the majority of the 2.7's had to be rebuilt with time certs by now, as they didn't last long from the factory. Although my 2.7 was not rebuilt...

I would recommend fresh top end gaskets (reseal the chain housings and cam towers too) when installing a 2.7 (or any used motor). My old one leaked like crazy! Although I guess it could be a rabbit hole if you start pulling the motor apart. At least install new versions of the easy to access gaskets, then if it leaks you'll be more easily able to find the leaks.

i thought you did not give a (garage level of interest and stress)

Damn

I had a 74 2.7 pre thermal reactors with 50k on it in my conversion 15 years ago. I rebuilt the engine only because I bought everything new at a vw swap meet for 100 dollars (what a deal) it was more of while Ivan at it. The engine had no time certs so I was going to do that while I was at it. I bought the time certs and looked at the course threads of the time certs and looked at how they were only .010 or so from breaking into the spigots that I decided not to do it. Keep in mind I have built hundreds of aircraft engines and also many porsche engines as well so take this with a grain of salt but the only reason to put time certs in is to repair pulled threads not to give extra strength..


Flame suit on

OK from Wayne's Book (pricing is 15 years old?), machine work you would do rebuilding a 2.7 but not on a 3.0.

$495 Line Bore
$350 Install Time Certs
$130 Oil system bypass mod
$29 Case saver inserts

=$1004, say *120% for today's prices = $1205

Looks like it is cheaper to rebuild a 2.7.

BTW His total was $3,300 for all the machine work (includes valvejob, rods and crank recon, etc...)

Total parts and tools was $2,872 which includes $1,400 for p&c's.

Grand total = $6200
This is a complete rebuild, only large purchase hard parts were the p&c's. EDIT-This Grand Total is older pricing from Wayne's book, please use your judgement for current pricing.

Quick note on the timecerts- They seem almost mandatory to me? The 2.7 I had you could only torq down about half of the headstuds... the other half wanted to pull out.