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Discussion Starter #1
Hello all
Looking for some insight here
I have a 916 engine with a fbf ama kit (crank, rods, pistons, 955 overbore) and also "G" cams and headwork.
I am wondering how to fuel this thing.
I have a p8 ecu from a 916 strada and a set of dual injector throttle bodies.
I am not sure if the strada p8 ran dual injectors or not.
I also don't know if an eprom can be taken from a 1.6 and put in a p8.
I also think that I read somewhere that the 996 fired both injectors together, while the 916 sp and sps only fired the second injector as required.
Does anyone know how all this stuff works?
thanks
 

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P8 computers can do 4 injectors. The 996 dual injectors can be used on a 916 without any problem. Find someone who can set it up for you. Doug Lofgren can do it. For street 996's the duals were not needed and many went back to the single setup. The shower system was/is superior.

G cams and such are not very good for street use, SPS cams work much better for that, even degreed stock cams with some high comp's and big valves work great for street. There is so much to know about those bikes and I'm not going to ramble about what could be and what was done to make them work. :) An 848 with slip-ons and a Nemesis/Microtec is stronger, faster and a lot easier to use today.
 

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Before the 996 model, only the SP and SPS bikes had dual injectors. Those earlier bikes use the larger P8 computer which is capable of firing the injectors sequentially, meaning that the second injector sprays only at the higher engine speeds.

All 996's came with two injectors per cylinder. The 996 is controlled by the smaller 1.6M computer which is incapable of firing the injectors sequentially, they both fire together. Unfortunately, the engine does not run well with both injectors firing at the same time, especially at low rpms where spray durations get too short to get good spray patterns. The fuel dribbles out at low rpm, so to speak.

According to FIM, dual injectors are not needed unless you're making more than 120HP, and so they have developed a single injector chip for the 996.
 

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Hello all
Looking for some insight here
I have a 916 engine with a fbf ama kit (crank, rods, pistons, 955 overbore) and also "G" cams and headwork.
I am wondering how to fuel this thing.
I have a p8 ecu from a 916 strada and a set of dual injector throttle bodies.
I am not sure if the strada p8 ran dual injectors or not.
I also don't know if an eprom can be taken from a 1.6 and put in a p8.
I also think that I read somewhere that the 996 fired both injectors together, while the 916 sp and sps only fired the second injector as required.
Does anyone know how all this stuff works?
thanks
That is pretty much what I am running in my 888, my set up:
P8
955cc DISPLACEMENT ( 96mmBORE, 66mm STROKE )
DUCATI CORSE RACING ENGINE CENTER CASES
DUCATI CORSE OMEGA 12 1/2 TO 1 FORGED PISTONS
DUCATI CORSE DUAL INJECTOR THROTTLE BODIES
DUCATI CORSE VLO3 EPROM CHIP FUEL MAPPING
DUCATI "G" INTAKE CAMS
DUCATI "B" EXHAUST CAMS
CARILLO RODS
FLOW PORTED CYLINDER HEADS
LARGE CAPICITY OIL COOLER
NICHOLS FLYWHEEL
50mm POLISHED STAINLESS STEEL FULL SPAGHETTI EXHAUST SYSTEM

Bike runs great but set up takes time, good luck
 

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Yes, single green side-feed injectors are definitely done supplying fuel at 120HP.
The P8 is capable of using/controlling 2-inj-per-cyl. You will need 916SP wiring harness unless you can add 2 more injector plugs to the existing harness. That would require pins for the M-M plug.
I haven't done anything like that so I don't know about compatibility between 888 SP2/3/4 harness and 916 harnesses.

After the engine assemply is known to be correct, your results depend more on tuning than anything else.

Since Ultimap/FIM closed their doors (as if 'they' were any more than Duane) we have been trying to supply folks with chips and it only confirms why I have wasted my life tuning. You can't buy a 'chip' that will make your bike run properly.

That is why Duane produced the Hand Held Terminal. It would support adjusting a chip that was made for a certain 'build' so that it worked fairly well on another example of the same 'build'.

We recently sent a chip to a guy who has built a 955 and he said the bike only makes 65HP.
The chip is set up to deliver enough fuel to to make about 115HP. If the bike makes 65HP with enough fuel for 115HP you might expect it to be a little rich. It is!
And, when he tried the -5% chip it made a little more HP, like 72 or something.
Fred told him (and I would have told him the same thing if I aswered the call) that the problem isn't the chip, but the engine.
If his engine made 120HP it would be a bit lean, if it makes 110HP it would be a bit rich, instead it processes just over 1/2 the air that it should and it's very rich.

Fuel injection is waaay dumber than carbs, but it's way more tunable.

So. yes you can figure out how to run 2-inj-per-cyl and the P8 will run it, and it needs to be tuned and can be tuned properly.
There aren't enough of those obsolete 27C256 chips left on the earth to just throw chips at it.

Doug
 

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Discussion Starter #6
thanks for the help, guys
I guess I will try to steer clear of the 996 set-up, and keep my eyes out for a 916 sp wiring harness.
 

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fastcan, you may have misunderstood.
You first posed the question about using a P8 computer. Explanations followed.
Along with that, was the point that a single injector per cylinder won't feed any more than 120HP.

Well, the 996 16M set-up will give you the 2-per-cyl that you need so you could use a 996 wiring harness and 16M ECU.

No matter, what you use it will need to be tuned.

Doug
 

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Discussion Starter #8
thanks MOPERFSERV.
I got that.
The 996 setup requires a p16 with the "b1"
It seems to me that the 996 setup does not work well, as many people run them on one injector with a fim eprom.
I have a p8 from a strada model, so if that will work, the wire harness should be all I need.
I am not expecting to throw a pile of parts together and not have to tune it.
It would just be nice to show up at the dyno with the right parts in place.
Thanks
 

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>It seems to me that the 996 setup does not work well, as many people run them on one injector with a fim eprom.<
I might sound like a broken record but I feel the need to correct this common mis-understanding.

Since the single injector runs out of fuel before 120HP a properly set-up and tuned 996 goes lean with a single injector chip.

The 996s had several glitches that I have always been able to address with a custom calibration.
Those glitches don't always go away with an FIM Hand Held Terminal doing zone changes.
The single injector change (first done by Matt Spencer using a 'Senna' chip, as far as I know) does improve the responce when the cal isn't custom.
So, I'm not saying that there isn't some advantage to the single injector scheme, but they all need custom calibrations. Believe me, I have created cals for a bunch of them and each one required as much work as the one before. If I could have saved time by using a previous cal I would have. And, I've tried it every time.

What all of this means is that the 2-inj-cyl isn't an inherently flawed scheme, they all need tuning.

How are you going to tune our 955?

I probably have a calibration file for a 955 2-inj-cyl P8 set-up. But it will still need tuning because of injector flow variations and fuel pressure variations.

I have never seen a chip work to anything like a satisfactory level.

If your injectors were matched (all the same at all RPMs) and the same as the vehicle that the cal was created on (assuming that the engine that the cal was created for actually used matched injectors). And, your fuel pressure was the same. And your ports were the same and the cams set to the same numbers and the exhaust system was the same, then the chip that worked on the first engine would probably work OK on yours.

That is the reason FIM created the Hand Held Terminal. For that situation, percentage changes in 7 different zones will go a long way towards making it run right.

Doug
 

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I wouldnt spend good money on a 12 year old harness and ecu, look at using a 998 harness, injectors and ecu then you can Nemesis or Microtec it. Also, the "G" is the worst of all Ducati intake cams, though a great exhaust cam.
 
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