Why EFI?, maybe excellence was expected and they came as close as they could.. Options

[RacingDreamz]

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

[stugray]

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?)

[Mueller]

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? (IMG:style_emoticons/default/wink.gif)

[zipedadoo]

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.

[r_towle]

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?

[Mueller]

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.

[914_teener]

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?

(IMG:style_emoticons/default/agree.gif)

Why the voyeuristic drama?

Work on your three cars and share your experiences.

[Jason74914]

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

[Bulldog9]

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...

Did Porsche eff up?

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

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

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

WHY DID THEY DO IT?????

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.

[falcor75]

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.

[Gunn1]

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

[ChrisFoley]

"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."

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.

[somd914]

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.

[barefoot]

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.

[era vulgaris]

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.

[DBCooper]

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.

[Mueller]

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.

[Bleyseng]

The MPS is quite tuneable but you just have to learn how to do it. (IMG:style_emoticons/default/piratenanner.gif)

[SirAndy]

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

You need to find better "Gurus" ...
(IMG:style_emoticons/default/poke.gif)

[Mark Henry]

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 (IMG:style_emoticons/default/bs.gif) your HP numbers are, torque is king.