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Posted by: tornik550 Nov 27 2014, 01:55 PM

I recently purchased a 911e 2.2l engine. Befor I install it in my 914, should I change carbs? A previous owner at some point changed from MFI to zenith 40 tin carbs. From my understanding, this is probably not the best setup for a 911e 2.2? I have looked at the different options, which do you think is most appropriate taking cost, hp/torque gains, drivability...

1. Leave the zenith carbs
Pros- I already have them
Cons- probably better forming options

2. Change back to MFI
I probably can't do this one. I have no where to obtain the setup and I really am more comfortable with carbs

3. Change to weber 40 Ida's
Pros- ? Power?
Cons- expensive. Most likely between $2000-$2500 after rebuild

4. PMO carbs
Pros- improved overall performance compared with the zeniths. Easy setup. Is it worth the cost?
Cons- very expensive-$3600.

Here are some other things that I am doing to the engine other than basic maintenance. Pertronix for the distributor, new plug wires (clewett), msd 6al (I already had this), msds headers.

I do not plan on racing this car anymore, just spirited street driving.

Posted by: type47 Nov 27 2014, 04:50 PM

None of the above. I think you should do a single plug Clewett TEC-GT total engine management system

http://www.clewett.com/index.php?main_page=product_info&cPath=2_56&products_id=14&zenid=a5dbb585fad0cb0d09c91f3ed290f0c2

so that if I buy that 2.2 local to me, I will have an easy install after following yours.

Posted by: matthepcat Nov 27 2014, 05:19 PM

I agree with the above. I have a 2.2s motor with weber 40's.

Nice performance, but I wish I had FI.

Posted by: Mark Henry Nov 27 2014, 05:29 PM

Is it a running engine?
If it is clean and get it running on the zeniths first.

Posted by: tornik550 Nov 27 2014, 05:43 PM

The engine is a very clean, running engine. I suppose it make the most sense to stick with the zeniths until I get everything installed and running.

I would like FI but $6500 is a lot of cash.

Posted by: type47 Nov 27 2014, 07:22 PM

QUOTE(tornik550 @ Nov 27 2014, 03:43 PM)

Posted by: johnhora Nov 27 2014, 08:53 PM

QUOTE(Mark Henry @ Nov 27 2014, 03:29 PM)

Posted by: ClayPerrine Nov 27 2014, 09:11 PM

If you were closer, I would help you with the MFI. The system is old, cantankerous, and frankly not easy to work on. I used to fix cars for a living, and I had to pay Ed Mayo to teach me how to work on MFI. It was worth the investment. Properly setup, MFI will give you better performance than carburetors of any kind.

But there is NOTHING that can match it for throttle response, and the SOUND is just pure audio porn. I have MFI with K&N watershields on the stacks, not so it can breathe easier, but because it sounds better. If you have ever seen the movie LeMans, you have heard the 917's MFI scream at full song down the Mullsane straight. I can get the same sound out of my car at full throttle.


Now if you already have the Zeniths, get them working so you can drive your car and enjoy it while you determine what you want to do.


If you want to get Electronic Fuel Injection that you can turn the key and drive, swap the motor for a 3.2 Carrera motor, complete with the injection. It will bolt into a 914-6, and with a little wiring you get a car that starts and runs like a new car.

Remember, everyone here has an opinion. But it is your car, and you have to be able to enjoy it. So listen to everyone and pick what YOU like.

Posted by: Mark Henry Nov 28 2014, 12:06 AM

I see you have an ad wanting webers, I'd really stick with the zeniths for now. I've worked on the zeniths and they are good carbs. The ones I've worked all were set up all crap often linkage issues or vacuum leaks. Guess what...Webers will run like crap with linkage issues and/or vacuum leaks.

I'd get what you have sorted, drive it, then you can think about upgrades. At least that way you'll know if the changes you did made any difference.
You have a lot of work (and money) ahead of you, don't get bogged down obsessing over an known running engine.

Posted by: roblav1 Nov 28 2014, 12:34 AM

I am one of the guys who said that the Zeniths are not optimal for the 2.2E. But the engine can still be made to run well on them with correct tuning and linkages. I agree with the guys who say to get it running on the Zeniths. You own them already.

One of the reasons I spent the money for a 993 3.6 is that it would have cost me more money to build up a good 3.0 liter case and then end up with less power, worse fuel economy, and much more time involved. Intakes and spark methods for these engines are quite expensive. Stick with what you got for now.

Posted by: Tom_T Nov 28 2014, 01:47 PM

IMHO if it were mine then I'd go back to the MFI cuz the 911E was set-up that way to provide the balance of the most versatility + best perfermance as a DD + sport driver! I always loved those early E's!

Most who changed the MFI & EFI on the 911/914 of that era did so cuz they didn't understand them & couldn't or wouldn't learn them, but they saved the royal PITA of carb balancing, twitchiness - esp. at idle, rejetting for altitude, etc. which multi-carbs demand in order to run well.

I also like cars of the era to represent that era & the technology then, unless you're dealing with a trashed or low resto value car that just doesn't waqrrant originality & the challenge of parts finding.

And the 911 MFIs are far better supported by Porsche & aftermarket than are the 914 EFIs!

BTW FWIW - Dave W./toolguy had a pain with PMO's he'd tried on his 70-6 IIRC, & have heard similar from other 911 owners in the SoCal area, they being not quite up to the quality of Webers.

Posted by: mepstein Nov 28 2014, 01:58 PM

QUOTE(Tom_T @ Nov 28 2014, 02:47 PM)

IMHO if it were mine then I'd go back to the MFI cuz the 911E was set-up that way to provide the balance of the most versatility + best perfermance as a DD + sport driver! I always loved those early E's!

Most who changed the MFI & EFI on the 911/914 of that era did so cuz they didn't understand them & couldn't or wouldn't learn them, but they saved the royal PITA of carb balancing, twitchiness - esp. at idle, rejetting for altitude, etc. which multi-carbs demand in order to run well.

I also like cars of the era to represent that era & the technology then, unless you're dealing with a trashed or low resto value car that just doesn't waqrrant originality & the challenge of parts finding.

And the 911 MFIs are far better supported by Porsche & aftermarket than are the 914 EFIs!

BTW FWIW - Dave W./toolguy had a pain with PMO's he'd tried on his 70-6 IIRC, & have heard similar from other 911 owners in the SoCal area, they being not quite up to the quality of Webers.

Posted by: JmuRiz Nov 28 2014, 02:46 PM

Never heard of people having issues with new PMO carbs. Where these people using used PMOs not setup for their cars?

Doing EFI or PMO is gts smart move, if you're made of money get a real E MFI setup
There is a guy in the PNW that does his own EFI systems using all kinds of throttle bodies (MFI, Triumph, other) and his are a LOF less $ than Clewett.

Posted by: Mark Henry Nov 28 2014, 03:47 PM

Almost everyone that has issues with carbs have no clue of how to set them up in the first place. With dual carbs a lot of the time it's a linkage issue, then ignition, jetting, vacumn leaks and lastly the engine is just plain beat.

MFI is great... but have you seen the prices peeps are asking for them

Stay the course with the carbs you have, get it running, see how it runs and then research and decide if you want to try something else.

BTW If one was to go EFI you could always gut and mod the zeniths to be TB's

Posted by: stownsen914 Nov 29 2014, 07:12 AM

I'm a DIYer and have tuned PMOs and MFI on two different racecars, and Weber IDAs on my warmed-over 914/4 years ago. PMOs seem pretty easy to work on from what I can see. MFI has a bad rap in my opinion. It's not that hard to work on - just not as convenient to adjust, and most people don't understand them so knowledge is generally more limited. And of course MFI stuff has gotten really expensive.

I'd run it with Zeniths and keep your eyes peeled for whatever you decide to put on it. Eventually you'll find what you what at a decent price.

Scott

Posted by: PancakePorsche Dec 2 2014, 02:47 AM

FWIW, I dicked for months trying to get a used set of old weber IDA's to run properly on my 2.7. I got so frustrated I began loosing interest in six conversion project.
I finally called Richard at PMO who set me up with preset PMO carbs. I installed them, started the car, and it went almost perfect idle right out of the box ! Final tuning was a breeze with further assistance from Richard.

Not cheap, but well worth it IMHO. Just my 2 cents worth.

QUOTE(tornik550 @ Nov 27 2014, 11:55 AM)

Posted by: 9146986 Dec 2 2014, 07:21 AM

Good carbs are not that difficult to tune, including Zeniths, but Zeniths are notoriously problematic, as are carbs that are 40+ years old.

Fuel injection is a superior fuel delivery method, but retro fitting a car with any injection system will require a learning curve.

My .02 would be to save your money and get a new set of PMO's.