I'm going to put a 6 in may car once the restoration is complete (about a year from now). I'm starting to look for a motor for it now though.

I really like the 3.2. Modern FI and with a Steve Wong chip and freer flowing exhaust, it's good for 250hp. But, all of the engines I am finding are high mileage meaning they are going to need rebuilding sooner rather than later. They are running around $5k.

So, I am wondering whether or not it might make more sense to find a 2.7 or 3.0 case and just rebuild from that with that same hp target in mind. It will cost more than the initial $5k the 3.2 will cost to buy the case and rebuild BUT it will be completely rebuilt when it goes into the car. A little more $$ upfront but won't have to take that 3.2 out in a couple of years and rebuilt it.

Thoughts?

I don't know which way to point you but I can say if you go 2.7 make sure it's a later aluminum case & I believe the biggest it can go is 2.9L. Pelican has those pistons for $5K!

Carbed w/ crankfire ignition is very reliable & sounds great . Goes pretty fast as well .

The bigger 3.0L+ engines have great HP and lots of lowend. If you want a rev'r I would go with, no bigger than a 2.7. I want a 2.5S engine.

I'd suggest the 3.2 rebuild with the wong chip.

You can go with 964 cams (even more low-end torque and overall power) and up the compression. Go with the headers and a good 2-into-1 bannan style muffler, you'd be rockin for more than 250hp. Good part is, you can keep the motronic injection and it'd still be reliable.

After just completing a conversion, my vote would be to go with a 3.2 (or larger) with EFI. It's so trouble free, gas mileage is good, power is fun and it's pretty much "plug and play". You basically get it all. If you go with an engine with CIS and are not familiar with it, you will go nuts. A 3.2 is worth the extra money and for a few bucks more you can get a 3.6

Only way I would "buy" a 2.7 is if it was really cheap. If you do get a 2.7 I wouldn't run from a mag case. Make sure it's straight, install the inserts, keep it cool and make sure it has the the later fan on it. You won't have problems. Most 2.7 problems came from thermal reactors and the subsequent overheating. Done right, you won't have either.

Good luck....it's a lot of fun!

PRS914-6, I've been following your 3.6 conversion. and

sounds like a 3.6 requires more work in our cars than a 3.2? As I said, I really like the idea of modern EFI: starts right up whether warm or cold, better fuel economy, etc. I'd REALLY like a larger engine in there. Just wasn't sure if the extra $$ for a high mileage motor made sense in comparison to rebuilding from a 3.0 block.

I guess the answer is to buy the 3.2 and then just budget for a rebuild in a few years.

I'm biased towards the 3.0 because that's what I have in my 911SC and the engine I purchased for my /6 conversion. I personally believe this is the best bang for the buck 6 for conversion but not with CIS, carbs are the way to go.

You might be right but what's a set of carbs cost?......I could almost rebuild a 6 for what a new set costs....over $3k now for PMO's and it'll never run as good overall for a street car as EFI. It might put out more power but not run better in all conditions.

Just my $.02

If you are going to "build up" as you refer to it, you want to start with a 7R case.

As for a rebuild on one 911 engine over another, the differences in costs are relatively small. . . Assuming you are going to do it right. You need to split the case, drill the oil galleys, replace the oil pump and true the alignment. 7R cases and up and going to cast basically the same. Once you get to the top end, the only difference will be the cost of the P&C's.

I am percolating on a 6 conversion too. Given that a 3.6 is just way too expensive, a 3.2 makes a lot of sense. Take your compression as high as you dare (or can afford if you twin plug), 964 or 20/21 grind cams and a free flow exhaust, tell Steve Wong what you have for a custom chip and you will have a great motor.

7R is magnesium. Bad idea. They have warpage issues, and lapping the case halves plus an align bore doesn't get cheaper. Keep in mind you can only do that so many times before you have other issues arise.

3.2L or bigger. if you have the $$$, don't even bother with anything smaller/older.
modern FI, bulletproof design, plenty of HP out of the box with stock internals.

you won't have any regrets ...
Andy

Click to view attachment

You're right. . . My mistake. 7R were the last of the old cases used on the '74-77's. Better than the older 5R but not much. A 3.0 SC case and newer is a much better choice.

I have had a 1986 3.2 Carrera motor in my car for 2 seasons. It was reported that the engine had 66K on it when I bought it. Runs great, starts right up every time. I would estimate 1 hr of autocross runs and 6 hours of track time on the motor in 2 years. I drive it to most events and on the weekend sometimes.

Just a/x'd this morning, shared the car with Britain. Tires are shot, last one of the season.......No motor plans for next year.

If I go with the 3.2, I probably won't build it up beyond a chip and an exhaust. That would be enough hp for me. I was just wondering if, cost wise, it made more sense to buy the 3.2 with high miles (my preference really) or buy a smaller longblock and rebuild from the getgo.

i would say 3.0 or bigger.....
and i would stay away from a 2.7, unless it was darn cheep...or had been rebuilt ...and was cheep.....
some good books available on the subject
if you are planning on rebuilding dollar costs for a 3.0 or 3.2 will most likely be cheeper than a 2.7 due to machining costs on the case
my two cents

I picked up some Weber 40's local to me for 810.00 in great shape. I agree FI is better across the board in most conditions but carbs a average guy can work on if need be. What ever floats your boat.

Yes, stay away from the 2.7. I got only 7 AX seasons out of mine....actually, it came up one AX short of 7 full seasons. Now I gotta tear into the thing & figure out why it's not running right. That'll prolly cost me a couple grand....what a POS!
Not only that, I figure I was getting 2.5 MPG out of the thing.


Way back when I was young, an old fella told me
"I hates snakes & spiders & talkin' to ignorant people."
That seems appropriate here.

I don't get the 2.7/mag case hysteria. There are some amazing 2.7 RS+ spec engines that will walk all over a motronic 3.2L. It's true that the mag case isn't as strong as aluminum, but that doesn't mean it will turn to dust if you build a performance motor out of them. Once the case updates are done, they are very reliable and have a good service life. For a street motor, there's absolutely no reason to be afraid of using a 7R case. Plus a good 2.7L core can be had for next to nothing.

It just depends what you want. A late model fuel injected motor makes for an awesome daily driver, but there is just something cool about an antiquated, fully mechanical motor, a la 60's/early 70's.

A new corvette is an amazing car in terms of performance and value, but would you rather spend the weekend racing a corvette or a 914-6 GT, or perhaps a Carrera RS? Different strokes for different folks I suppose.

I'm biased, but would say 3.2 any day.

The track car now has 14 years track events on it. I put that one in a long time ago. It gets annual valve adjustments and oil changes. I changed spark plugs a couple times and fuel filters a couple times.

The biggest issues it has had:

1. an air flow meter go bad
2. an idle stabilizer went bad
3. a DME relay had corrosion inside which caused it not to start once.

That is it.

I liked it so much, I put one in my street car. It gets better gas mileage than the stock 2.0 4-cyl.

I did use a fresh 901 trans that I put together with a billet intermediate plate. On the street, it should last a long time as long as I take it easy in 1st.

I'm happy with the 3.0 with CIS. I have a 911 with ~150,000 miles that I bought with at 98,000. Never had a problem starts right up rain shine freezing cold etc. This car is a daily driver or was when I was in the US. The 914 has a CIS 3.0 with 964 cams and headers. That too has been very reliable and makes enough power for the car to be scary fast. If I rember correctly it put out 188HP at the rear wheels when I took it to the Dyno with a nice flat torque curve. Only reved it to 6K. Taking it to 7K I would guess it would have been near 200HP at the rears. HP and torque had not even started to level off at 6k.

Nick

If its a street car 3.2 is the way to go.

Last year alone I did THREE 3.2 conversion. If you ask me its 3.2 or bigger I would not even consider the work for doing a 3.6 to be harder just different. I bone stock 130K mile 3.2 in a 914 is a blast. What are you saying the mileage is on the 3.2 motor you are considering? You have to remember that you will get almost every penny back out of that 3.2 if for any reason you needed to sale it in the future, I would even say you mite even get the cost of the rebuild if you are doing it yourself.
For five years I AX a 3.2 stock motor and yes power wise I was down with the injection and all being stock. But every weekend I finished my runs and got my time in Never even having to go into the engine bay. I was able to concentrate on driving and handling. Power is only part of the game I Have the Championship 3 times to prove it. If reliablity is what you wont a stock 3.2.
You would be served well by having a 3.2 but I must say a good deal on the 3.0L is also a great combo. That was to many the best motor Porsche ever built.
Whatever you do don’t forget to add some brakes and shocks.

Yeah, but how much more are all those 'updates' going to cost? The only reliable 2.7 mag case in 2.9 flavor I've seen is one where the owner dropped a pretty penny -- close to $14k in rebuild costs -- to make it reliable. We're talking upgrade to 964 fan, shuffle-pinned, some work to make a carerra oil pump work, different balance-shaft bearings and the machining for that. New P&Cs, non alusil. The costs add up. Penny for penny, it's cheaper and less work to start with a 930 case that's had all the issues addressed. That's like proposing the question of using a Type 1 case in leu of a Type 4, to spend all the extra money to make it comparable to a Type 4 in design. Not worth the money, unless you want to maintain "stock" RS status. But how many 914-6's came in RS flavor?

I found one 3.2 w/107,000 on it. He is asking $4k but it does not have the intake, DME, harness or ignition. I am not in a hurry for the motor as I still need to finish the rustoration on the car (I haven't even finished stripping the paint and what not, plus weld in new metal. etc.). I figure late spring/summer I'll be ready. But, if I find a deal on one . . . I also wanted to plan ahead for what I was doing so I did not have to backtrack. For example, might as well cut the 4 motor mounts out now, drill the bosses for the oil tank and filler and install the bulkhead motor mount prior to paint. Saves time and money.

Brakes and suspension have been/are being addressed. I've already got the entire front suspension including the steering rack, aluminum cross bar, Bilstein struts, rotors, calipers and hubs from a Carrera in the garage along with the matching rear brake calipers. A set of Eric Shea's modified trailing arms will go out back when the time comes. It will have a set of BBS 17 in rims, width yet to be decided (likely 7 and 9).

1. I've never heard (till now) of anyone swaping in a 964 fan.
2. There is no "balance shaft" in a 911 motor.
There is a lay shaft and it's had bearings in since the late 60's cases.
3. Shuffle pinning is recommended for over 7500 rpm work done on a regular
basis
4. The Carrera oil pump is identicle to the 76 & later 2.7L pump
5. 90 % of 930- cases came with Alusil PCs

........snakes & spiders and......

Hey hey hey, easy with the shit slinging.

I am NOT a machinist, I'm just telling you what was done.

Balance shaft - wrong terminology used - meant the shaft that drives the oil pump.

Shuffle pinning is also good to reduce warpage on engines more prone to it (like a mag case).

Carerra (3.2 and later) pump should be different, I'll run part numbers when I get home.

#5... We're talking the 2.7->2.9 conversion without alusil cylinders, not whether the 3.0 and 3.2's came with them.

........snakes & spiders and......

I've also heard the 3.2 with the wong chip is a great bang for the buck application. Nice reliable modern FI and some low-mid grunt too.

I'm more of a big 4 person myself but if I went six it'd be a 3.2 or a 3.6.

We just finished building a 2.5 911 ( my money and Blake's Labor) Be prepared to spend close to $10,000 and I didn't have to pay labor, just parts and machining. We.ve got a CE modifyed case, "Nickies" New cams , new springs , 10 X 1 rebuilt carbs SS valves and polished everything. It has yet to go the the dyno. looking for 230 HP ..we'll let you all know.

I'll 2nd the 3.2. High revving, high output, small displacement engines are fun, but you just can't beat the driveabiltiy of the Motronic 3.2.

Steve, you don't have to rub it in. Yes, Waide's 2.7 spanks my stock 3.2. His requires more maintenance but hands down, it is faster.

I wasn't referring to any specific examples, but if the shoe fits Actually, his car won't "walk all over" yours. I was actually referring to the twin plug 275hp beasts.

Now that you mention it, Waide's engine is a great example of a relatively affordable performance oriented mag case motor. No twin plug, no FI, just good ole fashioned performance. Let's see, 2100 pounds, 230 horsepower, 7000+ RPM's, = a good time.

There's no question that EFI is superior for daily driving and touring. However, for a nice sunday drive or day at the track the gap closes rather quickly. The 73 carrera RS was named one of the top 25 cars ever made by Automobile magazine. It had 210hp, 2150 pounds, 0-60 in around 5 seconds, and a driving experience 2nd to none.

I can't give you exact numbers but he is without question, faster. I have the road rash on my hood to prove it. I might have him once we hit 90....problem is, he can get to 90 much quicker and is already out in front. I'm just guessing of course. Truth be told, the more I talk about it, the less I like Waide.

Its the car and not the driver?

What are the differences between the 3.2 and the 3.6 conversion. Is it just the twin plug system? The motors seem pretty close in price in used condition..

wtih the 3.6 you have to modify the 914-6 tin a bunch, there is no on-engine oil cooler in the 3.6 either.

Street car - narrow body = 3.2 DME
- great power and easy to take care of

Street car - wide body = 3.6 DME
- great power, blindingly fast and easy to take care of


Personally, I have two 2.7's - one in a '75 conversion - the other on a pallet ready to be inserted into the race car chassis, once modified. Both with webers.

For me, personal choice - I love the sound of the webers under acceleration, and period correct for a mid seventies modified porsche sports car.

If I were doing a daily driver, a 3.2 or 3.6 DME would be my choice.

I've been told that the 901 will not survive behind a 3.6, that a 915 is a necessity, whereas the 901 will survive the 3.2 provided you don't abuse it. But, with a flared car already . . . What is the difference in price between a 3.2 and a 3.6?