Did Porsche eff up?

No they didn't eff up, they did the best they could with the new technology they had. It seems as though the technology was purchased by the folks at Bosch from the aviation component of Bendix. That said most Injection systems were originally good at idle and full open throttle, so primarily racing applications. So in there infancy not well suited for automobile applications.

Been reading on different types of fuel delivery systems and their pro and cons.


There are very few con's to todays EFI systems, there were however performance and reliability issues with the original designs. Even today Claims of increased HP, Fuel economy, drivability, reliability and so on....some still dispute
how much these differences really mean. It appears the main thing EFI does extremely well over Carbs is in the pollution factor, or in this case the ability to pollute less. Carbs are a some what open system allowing hydro carbons to escape/vent in to our atmosphere even when the engine is at rest, where as the EFI is essentially a closed system releasing no vapors or gases unless the engine is running and those gases are then coming out of the tailpipe from the exhaust cycle.

Many of the Guru's (about 5 to 1) prefer carburation.

The above Statement isn't correct, although what confuses this OP is the sheer amount of photographic evidence on this site and others including evilbay and CL showing most engine compartments with Carbs installed. Many here have spent thousands on their cars, and what do you see when the lid is lifted? a Carburated engine..... So while my intentions will be keeping my cars in their stock or near stock form, with EFI, I cannot understand why so many Carburated cars. (Because its easy isn't an answer, because its simple isn't an answer and because its cheap isn't an answer)

With this being the case, Did Porsche mess up when they went the EFI route with the 914?


I do not believe they messed up, I believe they did the best they could with the available technology they had. Granted they did sort of use the end user as of a kind of a guinea pig/test bed, but what manufacturer doesn't in some way.

WHY DID THEY DO IT?????


I think that just as much as seeing the Ljet and Djet as a performance and platform to develop future EFI systems off of, Porsche and others also incorporated EFI into there products to show they were progressive company's in design and practicality.
EFI, Unibody, Targa, Mid engine, four wheel disc, and many more attributes can be cited as Porsches View into the future.

I would like to keep my car stock with the factory EFI, but increasingly getting more difficult to do with so little information backing it up.


Above statement is also incorrect. In my case I think I am fortunate because I believe I have most the parts needed to reinstall the factory EFI's on all three of my cars. There is a plethora of info on both sides, but for now.... just for originalities sake, EFI will be the way I go.

To those that added constructive comments and or facts to this thread... it is much appreciated...to those that took this thread as some sort of attack on their beliefs, or way to "clutter" the site, I can appreciate how you feel, but I just see those arguments as shutting down the free flow of ideas and the give and take of facts that get each of us to arrive at our own understanding of the information.
Click to view attachment

How many modern cars do you see with carbs? There are reasons they've all gone FI. There's plenty of information to back it up.

There is difference between the EFI's of today and the system used on the 914.

Most of what I am reading is saying the Carbs provide a better Low and High speed power band, many go on to say the only spot the EFI is better than the carbs is a small portion of the Mid range.

Sure because the EFI was designed to run the motor in a stock or near stock configuration.
When the motor is built to those specs it will run better than it could on carbs.
Carbs are just a easy "Cheapish" way to build a performance motor and get fuel into it.
Really the right way will always be to run electronic fuel injection.
You can do so so so much more and have the car run 1000x times better than you ever could on carbs.
So for the 914 the reason people go to carbs is its cheap and easy compared to re engineering the fuel injection system to properly run a large motor.

There are too many variables depending on the build of the engine to just give an absolute answer. That's why I was speaking to the technology of carbs vs FI in general.

If you build an engine that gets out of the scope of stock FI, there are programmable aftermarket FI solutions that can match or exceed the performance of carbs while preserving all the benefits of FI.

Do you just make shit up? Various books on the older systems, plenty of websites on how they work, people that offer rebuild services and hard parts.

I'm wondering how old your reference is. Carbs are dinosaurs that will always have a compromise somewhere in their tuning spectrum while EFI is no longer really inflexible and limiting...

This is from one of those well respected services you mentioned below.

See all the made up Shit Below

"Will your engine make more peak power with EFI??
More than likely the answer to this is NO. At high RPM and wide open throttle carburetors really work well; so well that it has been hard for us to make more power with EFI on the dyno than a well tuned set of craburetors. The benefits to EFI occur at lower speeds in the form of drive-ability enhancements and torque boosts. This may defy what you've read somewhere else, but it is the fact concerning our own engine program.

Too often people buy into EFI for the wrong reasons, they have a perception that it'll cure all their problems and that it'll be easier to tune and work with than their current Carburetors. I hate to break it to anyone, but if you can't understand or effectively grasp the Carburetor concept enough to tune them you certainly won't be able to work with EFI."

Is it any wonder very few people want to inquire and ask questions here, when you
reply to people in that fashion.

Like Mueller said, please cite the source. And the build details. Otherwise the quotes are meaningless. (We'll tease him about spelling later. )

Are you talking about your engine, or something non-stock that is purpose built? You have to keep the build in mind when you reply with stuff like this.

Thicken your skin a little if you think this is hard fashion. We are discussing your topic with the interest in getting accurate information to the light.

Maybe you should not make such knee jerk reactions accusing people of making shit up.

Asking someone to thicken their skin is BS, it excuses bad behavior.

I would say if you cannot reply and ask for more info instead of making false accusations don't reply at all.

The quote and info on the previous post came from the RABY air cooled technologies site.

I suppose I made that up too.

Most of us respect Jake. If your building a budget uncomplicated race motor than carbs are nice, but take a look at all the modern race cars. Do you know of any engines running carbs at Lemans this year or any major race? Except maybe redneck nascar.
I never take the advice of one person. I google the question and compare the multiple responses.

Thank you for the reply

What I would value is if we could get on the same page. That's all. Dude, relax a little and get in the vibe we are trying to help you with.

Once again, you are taking things out of context and you have ignored my previous questions. If you want to read them again and offer relevant replies, we'd have something to go on.

NASCAR went to Fuel Injection in 2012.

Inside NASCAR: Fuel injection a 'really big step'

Jake's comment is based on running at the max. His statement that you posted above even states that EFI is better at low end / regular driving conditions.

I think the biggest confusion is how you started this topic. Looking at two 40+ year old systems you are going to find some +'s and -'s. Current EFI tech in the last 10 years has made it much more common place. Cheaper than a set of carbs? No. Better performance? 100%, unless you are Jake, who can tune a carb in his sleep.

Did Porsche eff up? Everybody starts somewhere, and the technology available for EFI then versus now is a whole different world. Look up when they started to develop their PDK that everyone raves about now. 1986 Derek Bell that almost lost the championship hated it. 2015 Derek Bell has a different impression:

Derek Bell Interview

Technology is a bitch.

Not sure where you got that info.

IMHO, carbs and FI are just different ways of getting fuel into a motor. FI offers a level of resolution that is impossible with carbs, but they're still just adding fuel to air. All things being equal, they're about the same from a performance standpoint. Any guru that doesn't know the value of either option isn't much of an expert.

Did Porsche screw up? No. FI works fantastic.

Thanks Clay!! I thought so, but wasn't going to take a chance in my response. Pretty sad that it took them until 2012 to switch to fuel injection.
I put a Weber on my 75 sirocco back in 76 and then dual webers on my 2.4 liter 1971 914-4 back in 1980 and then dual webers on my 2.7 six in my current 1975 914 back in 1986. For that last 16 years I have been running a stock 3.2 in the same 914 with the stock fuel injection. Lots of pros and cons, but I would never switch back to carbs

Who are these gurus you are referring to?

Open up Hot Rod or any other performance car magazine. Unless originality is desired, even the owners of old Detroit iron are ditching their carbs for EFI systems to gain both performance and reliability.

While the d-jet system has its shortcomings, carbs are dinosaur technology.

Perhaps one day someone will offer a more modern, plug and play EFI for the 914 but even in today's world I have to wonder who the 4 out of 5 gurus you refer to are?

If you enjoy touching your starter in any weather condition and your motor purrs to life with a nice idle, and you can start driving any time after. You have FI.

If you enjoy being able to drive in different elevations and your car behaves the same. You have FI.

The thing is, you're all over the map. You have a stock engine with FI, you are quoting Raby builds, and you are spewing irrelevant information with no substance about all the questions we ask about your application.

Be straight. Do you want results from a particular build? Otherwise, I guess I'll enjoy the drama with you.

See what I highlighted?
That is what why the factory used EFI. The fuel injection evolved through the years and what company doesn't want to be with the times?

They didn't build the /4 cars for max performance to be held at WOT for peak power. I'm sure the race cars used carbs, and those that didn't use carbs (the sixes and bigger engines used mechanical fuel injection which is too expensive and complicated for a street car sold to the general public.)

They could have easily done the carb thing with a more aggressive cam but they wanted to build daily drivers. (I think they offered dual single throat carbs on the 1.8s in Europe, might be the setup like the 1.8 in the classifieds right now)

Your post comes across as if attacking Porsche for using fuel injection which leads me to believe you are biased against it so no matter what I or anyone else writes you still won't like it and you'll still think Porsche compromised and made a mistake.

Yes, many cars had been converted to carbs by shops and owners, some due to needing the carbs due to modifications, others due to being more familiar with carbs (nothing wrong with that, I took the D-Jet off of an older 2.0 914 I had and replaced it with L-Jet because I know and like it better)

Did Porsche make a mistake by ditching bias ply tires for radials?

Hell, I just want my EFI to work so I can start the damn car...

You can have vastly different levels of tunability even in two "modern" EFI systems.

My son has a 2002 Honda S2000. If he wants to get a new header, or a turbo he is SOL because you cannot "tune" the EFI even in a car that modern.

My 2013 BRZ (with port AND Direct Injection) is about the most advanced you cen get in a car under about $100k and is completely user tuneable.
I can hook a laptop or a tablet to the OBDI port and tune the car myself from the stock 200 HP to almost 1000 hp with bolt on upgrades.

Not all EFIs are created equal.

The most major drawback to the stock EFI on the 914 was that it is an analog computer and cannot be reprogrammed or even modified by normal people.
(Some EEs would have a problem with it today - remember the move Space Cowboys?)

The lack of being able to modify doesn't make it a bad system.

I'm sure if Bosch wanted to and felt it a selling point they could have made the FI more apt for modifications.

I'm sure Honda had their reasons as well for locking it down as hard as they have.

Speaking of the BRZ fuel injection...wonder if any of the tweakable Subaru EFI systems can easily be adapted to a 914 /4 motor?

Another plus is that a modern fuel injection/computer controlled engine is able to run a higher compression ratio, enabling it to make more power and get better fuel economy than the older FI systems or carburetors.

Stop being so arguementative with every thread.
Start using search right here.

If we were in a bar or garage talking about cars and shooting the shit, would you start every conversation looking for a fight?

Why do that here?
Of all the topics that have been covered the most, cArbs versus EFI is the best documented and completely explained, yet you feel the need to stir up yet more drama....why?

Nothing wrong comparing carbs with EFI, however he basically calling Porsche idiots for using EFI and not sticking with carbs.

Why the voyeuristic drama?

Work on your three cars and share your experiences.

I also think there is some merit/value to keeping a car original.

Also, in addition to my FI 914, I own carb'd classics and when you look at the Summit Racing or Jegs catalogs, its ironic how much Holley, MSD and Edelbrock,etc are pushing carb owners (and charging big $$) to convert to an "EFI Carb Systems" they sell. Even they see the benefits and the future of their core business.

"Take a technological leap forward with a new electronic fuel injection system from Summit Racing." source link below

Just saying.
Jason

https://www.summitracing.com/search/departm...Order=Ascending

How old are you? If youre not like 16 dude, you are acting like total troll. Have since your first post. If you spend 5 minutes in this or any classic porsche forum, FI is the way most want and encourage people to go. Why did they do it? What a stupid question. FI was and is the best way to fuel an internal combustion engine used in daily/street driving. Hey pal, wake up call. YOUR CAR IS 40 YEARS OLD...... stuff breaks...

Just a tip for anyone wanting to go modern EFI instead if Djet är carbs.

http://www.thedubshop.net/#!blog/cxv7

Newly developed Megasquirt based ECU made for aircooled four cylinder engines.
If I wasnt already invested in another brand this is what I would buy today.

Thank you for the information

It appears that you've misinterpreted the quote from the Aircooled Technologies site.
It doesn't say carbs are better than FI.

It says its hard to beat carbs for making peak power at wide open throttle.
How much time do you spend driving your car at wide open throttle?

It says FI is better for torque (acceleration) and driveability.
To me that sounds like an endorsement for FI in a street car.

I highlighted one sentence to point out that the information presented is specifically targeted to potential customers of the Aircooled Technologies Type 4 engine program.
It would be a mistake to assume this is general knowledge to be applied in any circumstance.

BTW, I have a customer's car in my shop right now that has a Raby built T4 engine, delivered with an aftermarket EFI system installed - not carbs.

In respect to increasing displacement and power on a Type IV, sure carbs are the way to go see D-Jet is not tunable, with the exception of some minor tweaks.

But carbs have their flat spots, need routine tweaking, easily clog jets/passageways, etc. For a car I drive a few thousand miles a years and is a hobby for me, I don't mind tweaking carbs. If it were my DD, I'd stick with D-Jet.

But did Porsche (Bosch) screw up? As with almost question of the sort, it's a matter of opinion, but in my mind given the technology then, it was a big step forward.

And as others have mentioned, modern EFI with all of its feedback is awesome (I can swap tunes in my Suby in minutes based on desired driving style for the day). Granted, we are not talking D-Jet, that's where the early FI systems lead to.

If you are worried about originality, obviously stick with D-Jet. If you want to build the engine, i.e. increased displacement and power, you are pretty much limited to carbs or aftermarket EFI.

The EFI D-jet system first used on our 914's was standard in VW s type 4's in 1968 and was incorporated to meet emissions req'ts.
As manufactures of injectors for gas turbines, we were working with the Bendix co. Back then and had developed some of our own solenoid controlled injectors. That company did not have great commercial success but licensed Bosch for their patents and they then did very well commercially.
I had some of my own injectors in my 914 for a while as part of our modest test program at Parker.

Jesus dude, OU812, chill out man. You remind me of a guy I used to know who would do too much coke and argue any and every point he could just to argue!

FI is better. This from an owner of a 2270 with dual DRLA40'S. I'm sick to death of waiting for my carbs to warm up so I can drive, and I'm seriously contemplating selling my car because of it, and taking a reduction in HP to find a stock djet car. I just want to be able to turn the key and drive. No, I don't think Porsche screwed up at all.

To me the question itself, "Why EFI? Why did they do it?, Did someone mess up?" is so silly that it indicates a lack of familiarity with either, carbs or fuel injection.

Porsche had how many engineers back in the day? To think one or 2 people made that decision is silly.

If the FI was really that bad would we have as many running fuel injected 914's still running 40 years later? Of course the number get smaller due to one reason or another but it is not because the fuel injection was bad or flawed.

The MPS is quite tuneable but you just have to learn how to do it.

You need to find better "Gurus" ...

Lots of experience here and I can make both systems work well.
I can make carbs purr like kitten, but they will never work better overall than FI.


Porsche had to build consumer engines with a high degree of reliability, so yes they left a lot of HP on the table. Really this is no surprise that they do this as every single manufacturer does this.
Engines must start in all kinds of weather, FI adapts to conditions, altitudes, g-forces, be fuel efficient, etc.

In WW2 the benefits of FI were evident, Spitfires couldn't pull negative G's, the pilot had to flip the plane. In a dogfight it was no problem for a ace, but many novices died from this issue. The 109 pilots didn't have to worry about carbs.

Early systems had little wiggle room for performance and most wrenches had little knowledge on how FI worked so carbs were an easy off the shelf solution. Because carbs worked so well, most wrenches got lazy and didn't even want to know about the basics of FI, even how to service a stock system.
Mostly do to the advent of personal computers, by the mid 90's we began to see programmable EFI and the shift slowly began as wrenches became more tech savvy.

One thing as a builder that has always made me laugh is peeps so obsessed with peek HP numbers. To me the number is irrelevant for many reasons, foremost being the dyno operator and what correction factors he arbitrarily decides to use.
In a street car I don't give a poop what you claim your HP numbers are, torque is king.

Give him time, he'll find a guru saying carbs create more torque over EFI

Carburetor = controlled fuel leak.

https://m.youtube.com/watch?v=2sQJPZYSoUI

Even a self learning EFI needs more tuning to beat a tuned carb (on the dyno)
Even these guys couldn't deny the EFI advantages.

If I could get ITB EFI for the price of my good webers, i'd trade in a second.

Thank for the response Mark Henry.

Your reply along with a few others is all I was looking for, not asking the question because I already Know, Not asking because I am trying to create drama, Not asking to make things up.

On my first car I am thinking which way to go, I have the complete EFI for the engine, and I do have a complete solex setup as well, Being I am more inclined with carbs than EFI and I plan on doing the work myself, I wanted some opinions on which was "Better" before I have to spend more $'s to go the EFI route.

The question was did Porsche eff up, in other words did they mess up by putting on a EFI when the a Carb setup may have been better (didn't some of the European models come with carbs stock?)......Nothing more nothing less.

I have rebuilt many carbs set many float levels replaced many jets. so while not carb expert as many are here, I know enough to where I can make it work. The EFI on the other hand I have very little practical knowledge with this type of system.

Perhaps that is why I asked the question I did.

What I cannot understand is why I get all the smart ass comments, and PM's (you know who you are) telling me to back off on a specific subject matter, or that im giving to much time to a specific subject, and I need to stop.

So instead of jumping on my and others cases and making all kinds assumptions as to my age, whether or not I'm a Trol (not sure what that means), or whether I'm making something up, the thickness of my skin, etc., you could have replied like Mr Henry and the few others that did. With a common sense approach and answers to both type systems.

If my skin was so thin I would not reply at all......this is just as much my forum as it is yours. if you don't like the topic don't respond, Pretty easy.

In closing, I believe if you were to reread this entire thread you would answer the question posed by another members thread wanting to know where all the female members went. Many times women are Much smarter than Men, they wont hang around a site, where they know if they ask a question, rather than getting multiple answers and ideas, they get questions related to their character.

Thank you

It is they way you ask...or at least perceived by others.

Again, the asking if Porsche screwed up makes 0 sense and makes it look like you are trying to pick a fight.

There was no massive recalls or problems like when Chevy converted a gas motor to diesel (or Olds I guess) or when Chevy introduced the Vega with an aluminum block with no coatings on the cylinder walls. So yes, Chevy messed up.

I have a stock EFI we're thinking of selling or trading. If interested in trading your 2270, let me know.

Wow. OP needs to get over himself.

You made a bold assertion backed up by the thinnest of "facts". Most everyone disagreed with you so you react like an angry, drunken "truther". When you have dug yourself into a hole, the first key to getting out is to stop digging. Let it go and move on with life. If you really want to put a carb on you car then go ahead, no one really cares.

In Internet slang, a troll (/ˈtroʊl/, /ˈtrɒl/) is a person who sows discord on the Internet by starting arguments or upsetting people, by posting inflammatory, extraneous, or off-topic messages in an online community (such as a newsgroup, forum, chat room, or blog) with the deliberate intent of provoking readers into ...

I Goggled this....pasted it above.


I order to get replies....the WAY your posts read speak to this, in my humble opinion. Maybe it doesn't bother others. I'm somewhat ambivalent. I can always put your posts on ignore.

Glad that you know how to work on carbs. If you decided that you want to learn about D-jet this place is a great place to learn, and if you want to put carbs on a Type IV there are quite a few folks here that also know a lot about carbs too.

I try to let information inform ME as to my decisions I make....not the other way around.

OU, reread your first post that starts with "why did they do it?? did some one mess up" and then adds ....WHY DID THEY DO IT?????

Oh the horror!!! Why oh why did they do it??

Everyone knows they did it because EFI was the emerging state of the art and met the emissions requirements where carbs had no chance. For all these reasons it was "better".

Did it make more horsepower?..no. They werent concerned with that.

Is it the best for you??...who knows.

But it was certainly not a screw up and to even suggest it was a bit absurd.

That is what got the conversation off into the weeds.

By the way, even though I really like to hear the great noises that come from my triple weber set up (and think the popping, sniffing and wailing is certainly part of the allure of the early air-cooled sixes), I am working to finish an EFI/ITB set up so I can see just how great of a motor an early six can be when it is really optimized - with modern EFI and spark management. Just like Jake did when he was really trying to optimize a Type IV and the customer was willing to pay for it.

I would not bother putting on D-Jet, or even CIS. They were both somewhat lethargic induction systems and compromises limited by the technology of the times, but screw ups?? C'mon

So if you want a somewhat tempermental motor that will probably have snappier throttle response and maybe make a few more HP, go with carbs (and the right cam). If you want a smoother more efficient and gentile motor, and like originality, go stock injection. Your choice, neither is a "screw up".

There you go again...............

When you have to call people names and bring there Character into question, it proves you have no argument.

Its obvious there are some that understood my question and replied in kind.

I cannot help it if you and some others want to read something sinister into it.

Like I said before if you don't like the way I pose a question or start a post, you don't need to comment.

Buy the way I saw a nice Amplicar on Lake Minnetonka today, he was just driving down the landing ramp at Lord Fletcher's we watched it launch. Wasn't able to get very close but it looked like a 10+