NomoLag

So, after reading my Bosch CIS book, I think I may know what needs to be done to get some more fuel from this thing.

After talking with some of my Mustang buddies and seeing what they do for fueling, I think the answer lies in a rising rate fuel pressure regulator. Most folks call this an FMU. Basically, it adds fuel at a set rate based upon what "plates" are in the unit per amount of boost.

My question to those that are doing this: where does it go? After the stock WUR? In place of it?

So many people who are going fast are being secretive about it, and I really think that's a poor attitude to have, to be perfectly honest.

Just want to open up a discussion for those who may not be interested in the cost of going EFI.

Thanks,
Chris

philip200qt

You'd have to bypass the stock FPR and connect the fuel inlet and line to the fuel dizzy to the AFPR.
I run a vortech AFPR on my turbo miata to get more fuel into it, not the best solution.

boxerfan

I'll read my manual tomorrow and see if I can get an understanding of what you are talking about. More fuel is indeed the issue.

So... first up... Rising Rate Fuel Pressure Regulator: Plates and adjustemnt (or something like that)

WUR? What is this acronym? May become apparent when I crack the manual.

Time for bed....

AudiSport4000

WUR= Warm Up Regulator

boxerfan

Note:
CIS-E III has a higher system pressure than CIS-E.

Spec: 6.3 +/- 0.2 bar (88-94 psi)

Note:
A new fuel pressure regulator provides the higher pressure requirement. The fuel distributor is also modified. The top half of the unit is designed for use with high pressure injector lines. The new lines use flare fittings instead of banjo bolts and copper washers.

Note:
Timing must be set to 15 deg. before TDC +/- 1 deg.

Note:
The idles speed is NOT adjustable. The idle air bypass screw should be turned in fully against its seat.

Notice:
You will notice that this notice is not worth noticing so please pay no notice of this notice. ;-)

It goes on for a while... then:

CO value checking and adjusting:

Note: (here we go with the notes again)
If the CO value is less than 0.3 or more than 3.0% volume when the oxygen sensor is disconnected; adjust the CO as follows:

- switch ignition off
- remove rubber boot from mixture control unit
- centre punch mixture adjusting screw plug
- drill 2.5mm (3/32") hole in centre of plug approximately 3.5 to 4.0mm (964" to 5/32")deep

CAUTION:
Clean up any metal shavings. Apply grease to drill bit to catch loose shavings.

- screw in 3mm (1/8") sheet metal screw
- remove screw/plug using pliers
- reinstall rubber boot
- start engine and run at idle.
- adjust CO by turning mixture adjusting screw using Tool P377

* counter-clockwise (ccw): CO value increases
** clockwise (cw): CO value decreases

CAUTION:
When adjusting CO by turning idle mixture adjusting screw DO NOT push adjustment wrench down or accelerate engine with adjusting tool in place. Remove the tool after each adjustment and briefly accelerate engine before reading CO vlaue.

Nothing on plates yet but this seems to involve enriching the fuel supply.

nb::

Are we talking about the Probst book?

boxerfan

If the engine were tricked into seeing a temperature of -25 Celcius the cold start vlave would operate for about 11 or 12 seconds.

Has anyone tried to rig this to squirt at full throttle?

Ben Swann says:
"Cold start injector not recommended as it does not feed all the cylinders. I have asked questions regarding this before. You need to place an injector in the airstream pre-throttle - like on an insert in the Michelin Man hose, or plumb to the top of the intercooler, which is what I did - need to do carefully so as to not interfere with the hood latch mechanism. What I will do in the future is to drill and tap to mount the air-intake sensor into the flat spot on the manifold as that is where it is on the UrQuattro, and then use the place where the air sensor was to mount an injector. If you do this, let me know how it goes."

My question is why doesn't this cold start valve feed all the cylinders?

boxerfan

I'm looking in the Bentley.

boxerfan

It is all test, set up, replace. I guess this puts me in the learning column.

Please spell out your acronyms to start with.

duffWL

I was researhing this pretty heavily before my car got mashed. You can't really do the RR FPR as you would think. CIS uses different methods to regulate the fuel pressure. The WUR (warm up regulator) on our cars can be swapped to be rising rate. The early turbo cars (84-85) had a WUR that was rising rate as well as the Porsche 930. There are also other issues that need to be tended to...injectors, fuel lines, and the dizzy itself are all limiting factors. The first step is to get your CIS running correctly. Do a search for the_natrix on cardomain and check out his home page for some good CIS info. There's also a fellow on a Porsche forum that mods the WUR for Porsche 930's to get more juice. I talked to him and he said he would try the same for us if we get a rising rate WUR. He does the mod for $200.
I have more info for those interested..just mail me.