Well, I recently bought back the '77 e21 320i from the friend I sold it to and had a few questions about the mechanical fuelie setups. From my understanding, this model year was the last for it, and it should be the same or similar setup used on the 2002tii and 2002 turbo.
As it should be the same/similar, where could I find out if the fuel injector size differed, mainly with the turbo?
I only ask because I'm highly tempted to throw a cheap eBay tarblow kit at this thing for my own amusement, but want absolutely nothing to do with converting to EFI or carbs. I am also unsure of the voodoo black witchcraft that makes the Bosch MFI work.
Isn't the Kugelfischer system throttle position based with a three dimensional cam/plate/thingus that determines fuel output?
I mean, I know they DID make a turbocharged version, but they must have had some bizarre power enrichment scheme. Or maybe it just ran like crap off boost. The engines were massively low on compression, like 6:1 range.
In reply to Knurled:
Don't forget the metering cones....
I'm convinced the system should be able to take it, heck, if I could find just the exhaust manifold I'd just slap one of the vj11's I have lying around on it. I'm not after metric E36 M3loads of power, just more amusement.
In reply to Knurled:
Actually I think the 77's ran 9:1, and the 80-83 cars run 8.8. I'd have to look.
To the OP, all the e21's run mechanical injection, slight differences between the 77-79 cars and the 80-83 cars. I think the Kugelfischer on the 2002's was a little different than the e21s, but I may be errant in thinking so. With the advent of the e30, the M10's got L-jet efi.
As far as turboing the car, go to the bimmerforums.com e21 forum and look for JR Cooks build. He used to be on here, too, actually.
Somewhere around 250hp all on K-jet parts. Not all of them e21 parts, some might be Volvo and some Porsche, but all K-jet mechanical fuel injection.
There was a guy on bfc with an e30 M10 efi turbo build that occasionally hit the e21 section, and he was north of 300. I think he grenaded the motor when he went for 350, or maybe it was to get north of 375.
Wait... are we talking Bosch CIS or Kugelfischer?
If Kugel call Wes Ingram A nicer and more knowledgeable gentleman couldn't be found. I had the pleasure of chatting with him for a few hours while troubleshooting a 2002tii. That dude is awesome.
If CIS look into VW stuff. Folks have been turbocharging rabbits with off the shelf parts for decades. There are boost referenced warm up regulators and turbo based fuel distributors from audi, volvo and others.
I'm not sure entirely which it has, Bosch most likely. This and the tii seem to share the same cold start/idle injector however.
CIS aka bosch K-jet 
Kugelfischer 
CIS uses an airflow plate in the fuel distributor to adjust fuel.
Kugelfischer is driven off a timing belt on the engine and uses linkage from the throttle body.
Very different systems
The K-jet by the looks of it, and thank you for the comparison photos. I'll double check it tomorrow, but I'm pretty sure it's the k-jet.
K jet. Same as a billion Vws and Volvos and Saabs and Mercs andeuro fords and...
I think the biggest thing you'll need to source is a boost referenced fuel distributor off of a turbo Volvo. I believe there is a slight difference in the warm up regulator as well.
Cool CIS is pretty awesome and is what all the old volvo turbo stuff ran. It is all about pressures. You will need to make a gauge setup that can measure fuel pressures at various points in the system. Over 100psi in spots.
Read up on turbobricks or find a VW forum to see what folks are doing.
Was just discussing the low tech way a buddy made a ridiculously powerful turbo audi 5cyl powered Quantum Synchro wagon last night.
Boost referenced warm up reg is gonna be your first hard to find piece
I have a CIS fuel pressure gauge set I could send your way when needed.
WOW Really Paul? wrote:
The K-jet by the looks of it, and thank you for the comparison photos. I'll double check it tomorrow, but I'm pretty sure it's the k-jet.
Okay, much easier to work with. The tii and Turbo were Kugelfischer, a weird positive-displacement mechanical injection like a low pressure Diesel pump.
K-jet is stone simple, air goes in and fuel comes out. There's even a simple hack to allow closed loop boost fueling with a wideband. Very simple.
Nick (LUCAS) Comstock wrote:
I have a CIS fuel pressure gauge set I could send your way when needed.
That would be awesome
In reply to Jumper K. Balls:
I'm not worried about boost referencing for warmup, it can run like E36 M3 until that point since I let everything warm up. By chance do you think a rising rate FPR placed before the CIS unit would take care of fuel delivery?
Jumper K. Balls wrote:
Was just discussing the low tech way a buddy made a ridiculously powerful turbo audi 5cyl powered Quantum Synchro wagon last night.
The only ridiculously powerful QSW that I've ever been aware of had Megasquirt. The K-jet basically limits you to only 250-300hp for space constraint and fuel flow reasons. Get rid of the airbox so you can put the turbo there with a good header and suddenly you can make a lot more power, not just for more fuel but also the log manifold is crazy restrictive.
I'm shooting for "only" 350-400hp with mine... with a 10v. Doing things the hard way.
WOW Really Paul? wrote:
Nick (LUCAS) Comstock wrote:
I have a CIS fuel pressure gauge set I could send your way when needed.
That would be awesome
In reply to Jumper K. Balls:
I'm not worried about boost referencing for warmup, it can run like E36 M3 until that point since I let everything warm up. By chance do you think a rising rate FPR placed before the CIS unit would take care of fuel delivery?
Add a vacuum/boost port to the WUR, like the 924 Turbos did. You can also make it adjustable to fine tune it a little.
You'll also want a way to retard timing under boost to reduce detonation.
In reference to the injectors they are like garden hoses, make sure they are clean and have a good spray pattern. Other than that they will flow as much fuel as the distributor sends them.
http://www.924board.org/viewtopic.php?t=20665
Stefan (Not Bruce) wrote:
You'll also want a way to retard timing under boost to reduce detonation.
Get an OLD 5000 Turbo distributor, before they had electronic ignition timing control. I'm thinking this was '84-earlier. They had a pressure retard diaphragm on the distributor, and they looked like the same small cap Bosch distributor housing that everyone else used in that timeframe.
In reply to WOW Really Paul?:
PM my your pertinent info and I'll box it up and send it your way.
WOW Really Paul? wrote:
Nick (LUCAS) Comstock wrote:
I have a CIS fuel pressure gauge set I could send your way when needed.
That would be awesome
In reply to Jumper K. Balls:
I'm not worried about boost referencing for warmup, it can run like E36 M3 until that point since I let everything warm up. By chance do you think a rising rate FPR placed before the CIS unit would take care of fuel delivery?
Warm up regulator controls much, MUCH more than just warm up.
Edit:
It is also known as the control pressure regulator and controls overall system pressure. This is CIS and pressure is everything. On early cars it was used as a cold enrichment device and got the name warm up regulator but it does much more
In reply to Jumper K. Balls:
Ahh, gotcha. This is the type of stuff I'm going to have to learn. Good news I know about this one from when I bought it is that it has limited slip and a 5sp swapped already.
Warm up regultor is another name for control pressure regulator. I drive a turbo kjet car, and although it's supposed to have a referenced cps it does not and runs just fine. Volvos use a boost enrichment switch at 3psi to take care of extra fuel. Also lots of guys who go balls deep run a v8 mercedes fuel distributor with 4ports blocked off, volvo 240 group a cars did this as well. You can add more fuel pressure across the board by shimming the fuel distributor with a little washer. Do not take apart a fuel distributor, i repeat do not take it apart, its press fit from the factory and will leak. Instead pour a whole can of barrymans b12 chemtool ($3 seafoam) in the fuel tank and it will clean it out very well.
I only suggest to try kjet if your a luddite and machismist. save yourself a ton of trouble and just run megasquirt.
In reply to chiodos:
LOL, I understand K-jet more than I will ever understand EFI. I think I have Luddite tendencies.
FWIW, Audis did not boost reference the WUR. They just ran the hose to the clean air side of the airbox.
