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Hagerty
Hagerty Employee

The long, winding road to EFI

In the 1950s, auto engineers began to ditch unruly carburetors in favor of the fuel injection that winners and losers alike had successfully employed in WWII aircraft. Mercedes-Benz was first to bat in 1955 with a direct-injection system-squirting fuel into each cylinder instead of mixing it with air in the intake manifold-on its spectacular 300 SL sports car.
https://www.hagerty.com/media/automotive-history/the-long-winding-road-to-efi/
17 REPLIES 17
Air_and_Water
Detailer

VW (and very shortly thereafter Volvo) had injected cars for 1968, not '67 - unless you're talking about release dates rather than model years. It was a solid system and worked well for many years with little maintenance. I was using a car so equipped as a daily driver back in the '80s and it needed nothing from me. It's getting tough to source parts, but they're still out there running around.

Until reading this article I had absolutely no idea that Bendix was the initiator of the system and that Bosch bought their research. Kudos for filling in that (rather large) gap!
csnyder
Intermediate Driver

Can't forget the analog mechanical Bosch K Jetronic constant flow injection used by Volvo, VW, Porsche, and several others - quite successfully I might add - including the KE Jetronic electronically modulated emission controlled systems (AKA the K Jet Lambda)
Corkola
Intermediate Driver

I beg to differ. MOST WWII aircraft engines used carburetors, not fuel injection. Fuel injection was used on many German planes but did not see widespread use on Allied planes until the latter stages of the war.
Scary
Pit Crew

I don't think he meant most aircraft engines made, he meant most manufacturers eventually employed fuel injection by the end.
Scary
Pit Crew

Great article. I was aware of the invention of FI in WWII and that the Corvette made a few fuelies but until now hadn't known the full timeline on whom and what were the first to embrace it in cars.
I had a 1984 Mustang GT that was still a carb car, and had normal hydraulic lifters. When the '86 came out with FI and roller rockers, I couldn't keep up and that started my life of performance upgrades. In the end I gave up and bought a '89LX with the 5.0 HO since it was lighter, faster, and less expensive than the GT of the same year.
Teampantera
Pit Crew

I added an 8-stack IR-EFI system to my stroker. Love the look and gained 40 HP over my single flowed 830 Holly. Add 180 degree headers to the business end of a Pantera and few things look, work, or sound better
hyperv6
Gearhead

The real key yo FI was electronics.

Mechanical was very hard to keep in tune. The early electronics worked better but the computers were lacking.

Today we have the computers and now even the electronics to do Direct Injection to where we can run more compression or boost to get a cleaner burn that has the side effect of making more power.

Cooling that cylinder makes a difference as with the electronics to control knock or fuel mixture.
BMD4800
Instructor

The ability to trim and time each injection event has made significant improvements in NVH, which is the bane of all engineers dealing with I4 or V6 engines.
Inline8OD
Detailer

Corkola's right, German Bf/Me-109s and Focke Wulf 190s with fuel injection were a real threat in dogfights with otherwise terrific Allied pursuit planes powered by carbureted Merlins and Allisons. But otherwise Don Sherman gave us a typically fine overview of how and why we went from carbs to f.i..
BMD4800
Instructor

Buick 3.8 MPFI and SFI.

In 1984 Buick introduced MPFI 3.8s.

The 86 3.8, non-turbo SFI engine, in FWD cars and SFI turbo cars, was sequential injection and also used roller lifters, and a distributorless ignition. The non-turbo engines were 150 hp/200 lbs ft. Laughable now, but back then that was pretty impressive. Especially when compared to the 305 or 307 Olds.

farna
Advanced Driver

I wasn't aware of the capacitor problem, but did know that the electronics were an issue with the Electrojector as temps rose -- that explains why. According to AMC documents the Electrojector worked great in a 40-90 degree outside temp environment, get much out of that range (or in the high 80s in humid weather) and it wasn't very reliable. That's the main reason they didn't release any production cars after showing it off at Daytona in two new 1957 Rambler Rebels. AMC documents state that several Electorjector cars were made for testing, but AMC historians can only verify that two were made since two show up in photos together at Daytona. Probably at least one more left at the factory, but no documents give a number. Newer electronics solved the heat issue, Bosh solved the cold start problem by adding a temp sensor and an extra injector in the intake (you can see it in the diagram) that acts like a carb's choke.
BigMikes
Pit Crew

My old boss at the AMC dealer I worked for indicated that there may have been a few more that got out. He always said they had to swop one out for a carburetor. He was not one to make up stuff. I suppose it could have been one of the two.
Andretti
Pit Crew

The Bosh D-Jetronic EFI was pretty weird compared to today’s systems. I bought a used baby blue ‘72 VW Type III notchback around 1980 for my wife. Everyone knew she was at work since her car was so easy to spot.
Calls me on a pay phone yelling she’s stranded at the side of the road. Yes hon, I know it’s my fault she broke! Turns out it’s the mechanical voltage regulator stuck on full charge. Disconnected, it drove fine on battery voltage back to our apartment.
Really fussy system when it came to operating voltages.
Gary_Bechtold
Technician

With the Holley on the top I thought this would be more about aftermarket EFI. I guess it's more of a partial how we got there. Still cool story. The early FI systems are surely interesting.

bhart
Pit Crew

I am still running the D-Jet system on my 1973 Volvo ES, quite successfully. It's a simple system that is pure analogue electronics and serviceable with a test light and Ohm meter. It runs well and is more consistent than the SU carbs of the day but it's not perfect when compared to modern FI and I think that's where some people are disappointed. If you're expectations are with an early 70s frame of mind, it's great and that's how I enjoy this car.
hyperv6
Gearhead

FI Tech right now has a great system at a very low price. It single handedly phasing the Carb out of the street performance market. It has brought FI to the hone masses. 

tproveau
Pit Crew

I owned a brand new 1978 Volkswagen Rabbit fuel injected. I am no mechanic and don't even remember the size of the 4 cylinder engine! I do however remember all the sputtering/jerking it did when the injectors became clogged and I had to take it for repair which was a cleaning job on the injectors if I remember correctly. This happened three or four times and then, my mechanic who was a local dedicated VW guy said next time the injectors would need replacing at a pretty high price. The car was ok otherwise aside from being a bit of a tin can body wise, so I traded it in. It was just too annoying, and I think I heard much later the early VW Rabbits with fuel injection has several issues.
I know anyone can have issues, however I have never even considered a VW after that experience and it was my first brand new car!