Cole,

If you are going to race your car is is worth making sure you have even fuel deliver to each cylinder. Having the injectors flowed is part of it. Having the head flowed or rebuilt is the other half.

One guy here pulls his injectors in place, puts beakers under them, and pushes his metering plate down all the way after disabling the safety. I like!

We can be running 11/1 AFR and still have one cylinder go lean.


:)

Anyone know how far the metering plate on the CIS travels at full throttle? Or where the stall point is? How much more fuel is available when the metering plate is wide open? Perhaps a few might know this; I sure don't.

There must be something to this CIS system that we are missing because this is directly inline with the 'CIS Monster' thread that I started whereat that guy is getting over 600hp out of CIS. I don't claim to know this system a whole lot like I do EFI. Just how much fuel can a CIS system put out?

To overcome inertia; improved throttle response and to increase force on the plate to eliminate the stall.

I think he has found the limit with out major changes like drilling out the two other blanks on the fuel head for more flow. For all I know, he may have even done that. I think Porsche took that approach with one of there 924 race cars.

He also knows how to build a motor that will not lift and leak at the heads, that will stay together, and breaths very well. He also has a very efficient turbo.

His biggest trick is he is managing boost much differently that we are and goes much higher than 1 bar in the mid range. I believe he keeps pushing boost until he reaches the total fuel deliver capacity of the fuel head. Then, when the motor can not push anymore fuel, he starts pulling boost back fitting the boot level to the fuel deliver limit to achieve stable AFR's to red line.

His peak TQ is artificial and where he first starts to manage and reduce his boost level. His peak HP is where his motor is at its peak VE which is the same place we hit our peak HP. I bet he is pushing somthing around 1.5 bar in the mid range. That is just over 22 lbs. Many run boost into the 30's.

With our motors, our TQ curve is steep until we reach our target boost level. Then the TQ curve takes a turn as we hold our boot goal and we try to hold this to red line. This puts our TQ and HP at there natural points much as if our motors were normal aspirated.

He seems to be using a stock set of euro heat exchangers and probably a turbo with a bigger compressor wheel than we are even with the larger HF's.

This is repeatable with some effort but buget for rebuilds based on hours instead of miles if you track it.

I made some posts near the end of that thread.

:)

I suspect around 425-450 rwhp if full travel can be achieved in a way we can use it.

I spoke to the builder of the Rice Fueler many years ago. He modified WUR's to be vacuum sensing and for more fuel on boost. He told me that even with much lower control pressure (like the Andial Fueler gets) that he ran a motor at peak HP on the dyno once and was still able to push down the metering plate with a screw driver and flood the motor.

That is why I have been so interested in getting full travel our of the metering plate all these years.

Again, I believe full travel will get us to around where the IA head is getting us now. However, adding the IA on top of full travel should get us further yet. Say upto 500hp.

Thus, fuel dose not have to be the limit. It becomes more like sealing the heads, managing heat, keeping the motor to together, and making it breath well.

Boost and fuel are just part of what makes HP.

:)

Just had to see this again because it rocks!

http://forums.pelicanparts.com/support/smileys/wat3.gif

I'm like a kid at school :)

Below is an interesting uTube video on that Compressor Boost Valve mentioned above compared to a normal blow off valve.

I found that taking this approah along with fast reduction in conrol pressure upon acceleration and the righ AFR's made a big differance.

The BOV only opens to release boost on overrun to keep the compressor from dammage.

The other valve stays open letting boost past to keep the turbo spinning in reserve at idle and cruse and closes when boost is needed.

This is simmiler to wha I did on my C2T by changing the orientation of an adjustable CBV and playing with the spring tension. Mine was actually much faster. The advantage to the new system is the amount of air if may flow. My set up fit the standard Bosch CBV fittings.

http://www.youtube.com/watch?v=gvnBDlXyheI

:)

Keith,

No more racing for "The Old GUY"

I'm 66 have a Junk Pump and Cancer I'm doing all this just to see if acceleration
can set my defibrillator off, I'm considering this a Physics Experiment.

Steve is doing the fuel head now, injectors are soaking in a jar in the garage.
Having them tested next week. Billet injector blocks and DWUR coming.

Cole

When i had these two new hybrid K16/24's installed on my 993 lump

http://i139.photobucket.com/albums/q...NewTurbos3.jpg

http://i139.photobucket.com/albums/q...NewTurbos1.jpg

I set off for Le Mans 2008, i got nearly 2 miles down the road and the new BOV'S i'd had fitted

http://i139.photobucket.com/albums/q320/jbl930/203.jpg

Failed! What happened next was strange. The BOV's were second hand, they didn't open on vacuum. The right hand turbo stalled, the nut then came off the end of the shaft on the compressor side and the left hand turbo sucked it all the way around the back of the intake and into the compressor of the LH turbo, Basically destroying both turbos. Not a good day!
Stock Porsche BOV's in now and all is well, RS Tuning use the stock 993tt BOV's in even their most extreame road turbo builds.
Lesson being, use proper BOV's :)

Jonathan that gave me chills !!!!!!

Sorry man.

Cole

Jonathon dont think many people had the luck you have had,nightmare!!

That's why I think the gurney flap would be more efficient (not to mention easier to make). The air will have to travel over the flap at all angles of opening. In your proposal the plate is only effective through a small range.

HERE it is guys!!!....This is like a step back in time with this picture!

Finally got my mate who has got my catalogue to send me pic until he returns it however its been sent to me via mobile phone so aint so good quality!

It does mention quicker fuel enrichment due to the design so they also have went for that pitch

Cole was the "venturi plate just flat on the underside??,,if so cnc lathe is the way to go!!...I have a manual lathe in my garage and could machine them however with a CNC, you would just write a program and could turn them out a lot quicker,At my old work place my mate could knock them up on the side at very reasonable cost!

When you get results we will look into manufacture!
http://forums.pelicanparts.com/uploa...1236425780.jpg

For us with not so good eye sight it says!:eek:

THE FASTER THE AIR ENTERS YOUR ENGINE THE SOONER THE TURBO SPINS UP AND THE SOONER YOU GET UP TO SPEED,ITS THAT SIMPLE.AND HERE IS A WAY TO GET QUICKER ACCELERATION.OUR DOME SHAPED ALLUMINIUM VENTURI PLATE INREASES THE AIRFLOW PLATE SURFACE TO GIVE YOU BETTER AIR FUNNELING AND QUICKER FUEL ENRICHMENT.SIMPLE BOLT ON REQUIRES NO MODIFICATIONS.YOU WILL NEED A FEELER GAUGE FOR SETTING THE PLATE HEIGHT.

The MP "stalls" because the pressure differential between the top of the plate and plenum is zero. Steve at Rennsport solution's is the beauty of its simplicity. By modifying the fulcrum so that when the stall pressure differential is zero, the fuel distributor is at max fuel delivery.

You can also modify the air delivery to the metering plate. By redirecting the air to the outer or inner diameter of the metering plate, you're affecting the amount of "leveraging" force the air traveling across the plate. Everyone remember the mysterious cone in the air cleaner housing that sits above the metering plate?

Sounds like we're all talking about the same issue: how to get more force on the metering plate at large angles of attack.
Here's a question: how does the weight of the metering plate affect overall performance?
The best solution will have to be easy to implement and cheap. Otherwise, the benefits will dimish to the point that it won't make sense to modify CIS if the level of effort and expense gets close to the implementation of EFI.

I agree.
I suspect the mass of the metering plate would be based on the same principle of a lightweight flywheel.... inertia. The mass of the plate tends to dampen subtle variations of air flow over the plate for smoother fuel metering.

stup & 911nut

That's great that you found the ad. I would really like to have a copy of it when
you get it back.
I got mine from Chris Fisher in a box of 934 parts I bought from him. Chris was
on of the Principles of the original Power Haus. The only way I even knew what
it was is by reading an article in the April 96 issue of European Car that
featured the White Car. In the article it mentioned a high-flow fuel distributor
with a "special dished air-flow plate. When I found it in the box the disc, a copper
metering plate, and the mounting bolt were taped together. I remembered it
being mentioned in the article so I recognized what it was..
I called one of the old Power Hause guys yesterday and ask him about the
plate. He told me that Chris had seen one on a Mercedes CSI he had in his car.
They were screwing around with fuel distributors at the time and decided to try
it on the Porsche CIS. Chris's logic behind trying it was Mercedes would not have
added anything without throughly testing it extensively and it might be exactly
what they needed to get the metering plate moving. Power Hause did dyno the
engines with the plate and it did improve throttle response and plate movement.
He could not remember any of the dyno differences specifically. Apparently it
worked well enough because they had a local metal spinner make one with the
correct diameter for Porsche CIS and after testing had them made in larger
quantities and marketed them; hence you ad in Automation. Interesting price in
the ad, I was told they only cost a couple bucks each to make.

Cole

Well, there's a clue.
A metering plate made by metal spinning would be very light.
It wouldn't be expensive to make except for the tooling charge ($$$).

Can you explain in more detail Steve's modification? I apologize if I missed it.

Would it provide benefit in cojunction with the new plate? Or do you think the new plate might provide enough force to get the full fuel delivery without stall?

Cheers all.

RT

The big deal to me about the special MP is eliminate stalling of the MP and hopefully get it to not slow down as it approaches 100%.

If you want to effect how fast the MP moves of idle and cruse so we get an accelerator pump effect, do it with CP. I did this with my system and it worked great!

You can do it by converting the WUR to be "Vacuum Sensing" instead of boost sensing. That is what Porsche did on the 3.0 turbo WUR's and was done on a bunch of other cars.

For example. If we set the idle AFR at 14.5 currently we do not have very good throttle response with the current WUR set up because we get a lean spot off idle with acceleration.

If the WUR is converted to "vac sensing" the WUR will trigger just like with the boost enrichment dose at .5 bar boost.
:)

Now, as soon as we touch the throttle, CP drops and the AFR will richen to say about 13/1. This give us more power at the same rpms.

Thus, acceleration fuel!

If we get this right we will slowly increase our enrichment AFR curve to be just a little fat at TQ peak and then level off a a solid level approaching red line. Even with a big turbo.

While I don't have much input here on the CIS itself, I know the Synapse Engineering products inside and out. I've been using them extensively since their debut and know the owner(Pete) quite well.

If you have questions about them that pertain to this thread just ask and I'll answer where I can :)

I can't help but notice this thing looks like a cross between an old doorbell and one of those things that go under a furniture caster to keep it from rolling around on a hard floor, or the top of a small pot minus the knob or part of an old percolator coffee maker...

It looks easy to come close to guessing it's dimensions from the pictures.

J,

I have one (the photo on page 1) and it is at Steve's. He is going to install it
while he is doing my fuel head. I will have it back in a couple weeks. At that
time I will take some more photos and post them. If there is interest I will
take it to an aluminum spinner and have some made.

Cole

RT,

I don't think anyone but Steve knows exactly how or what is done to the
metering mechanism and, understandably so, he will not go into detail with
anyone.
From what I was told by Chris Fisher the velocity plate does allow the
metering plate to travel past the stall point in which case the metering
mechanism mod might not be needed.
I am going by the fact this device was engineered and used by Mercedes
and I have never known them to just bolt S--- on a motor or fuel system
without substantial R&D and Engineering. If it didn't help they wouldn't
use it.

Cole

Adam,

Thanks for the input and the offer. I just ordered mine this week. I have
read everything I could find and have seen no negatives Looking forward
to trying it.

Cole

[QUOTE=Thierry25;4527480]dear Mark

The andial controller is very limited in it action since it can not get the MAP information. It would be relatively easy to modify some resistance inside to change the duty cycle . But it is much more convenient to do it by programming the AIC controller ...would be much easier and much accurate.

the Andial controler doesn't controle the original lambda freq valve. The andial controle his own added freq valve.[/QUOTE]

Yeah, I'm aware of that. I think I used the term Lambda inappropriately. Frequency valve is more accurate. My Andial has been working well for several years now....I'm just tinkering with changing the "how" of how it works.

http://forums.pelicanparts.com/uploa...1236365567.jpg

It has not been discussed....trade secret, I guess.
But the thing(s) that could be done is putting the fulcrum on an eccentric bushing and modifying the end of the lever that touches the fuel distributor valve/plunger. How much of an eccentric or modification would be the trade secret. MY $0.02, of course.
The C2T X50(M50) H.O. engine used the same fuel distributor as C2T and the '87 930, but the air metering unit is unique to the X50. They did something different on these metering units. Dunno what though.

Subscribing.
I see alot of thought has gone into this thread, which is great. I am glad I am not the only guy thinking to himself about CIS.

My difference is that I have a "kit" on my SC 3.0. The only parts left from the kit are the boots for the metering plate inlet and the throttle body. I monitor lots of data; all analog, such as inlet temp to the airbox, CIS plenum temperature (effective temperature rise across the compressor), AFR and boost level. I am relatively low HP compared to what everyone is speaking of here, probably around 285 RWHP at 5.5 PSI boost, but it's certainly a lot more than the 161 RWHP I had as an SC. I have run various combinations of stuff for fueling, starting with stock CIS. That was good, until I got the revs up, and then it went lean. I then went IA modded SC head, which went rich all across the rev range. I went to a Leask WUR, which solved regular street driving and high RPM fueling, but I was pig rich at mid range at the track (I can't help myself, I love the car at the track). Then, I went to a Leask RPM solenoid switch, but that didn't solve the mid range problem.

So, I switched back to a stock CIS 3.0 fuel head, and I was back to good, except a tad lean at the track. Then I detonated the engine at Watkins Glen, so I have it apart, going back together now. Stephen at IA re-modded the head for me, so we will see how that responds.

My thinking on this is somewhat similar to the original premise by 911st...plate stall at the top of the rev range. If I could diminish the stall effect, I could run the stock CIS fuel head and it would all be good. I have considered RPM synchronized fuel pump pressure (Summit has one, God only knows what the drag racers use it for). I can drop control pressure, but to no avail. I am being underfueled at the extreme. I suspect the plate motion vs fuel volume delivery is slightly non-linear. I think the 930 setup gets you a better air entry into the plate area, but after that, CIS is all the same. If I recall rudimentary fluids from school, we have basically traded off velocity pressure for static pressure at the plate, as we are killing the high velocity area in the center of the velocity profile, and effectively making the plate function as a diffuser. Also, we are speaking of a mechanical device, with mass and inertia. I experience mid range over-rich conditions, which makes it difficult to get out of a corner at the track, which I attribute to the inertial effects of the metering device. I have also considered changing the fulcrum point, but that needs to be dynamically changing, like maybe an eccentric pivot point.

I like WERK-1's thought on the mysterious cone, which would tend to alleviate the condition somewhat. Does anyone have a picture of this?
The biggest problem is the damn CIS itself. I have spent enough money to go EFI at this point, but I am stubborn, and I just know this will work eventually. I really think that somewhere Porsche/Bosch had this figured out, but didn't put it into production...warranty claims, maybe?

Everyone else installs there BOV or CBV with the piston perpendicular to the boost pressure. This is the right way to do it but the boost side loads the pistons.

I ran mine so the position pushes against the boost and in the same line. It took a the spring tension to a small degree and the boost building up behind the piston that had about three times as much surface area to push the valve closed.

Again, my valve stayed open most of the time to keep the turbo spinning. Not like they are supposed to be run. Any time there was vacuum pulling in the intake manifold, they it was open. Like at idle and cruse. Accelerate, and they snapped shut.

Never though about it till now, but I can understand why your BOV may have failed with all the side loading. My set up would likely have kept that from happening and given you faster boost.

Pat,

I took a couple pics. for you.The cone is tacked to the top of the air cleaner and extends down 2.25 in. it tapers from nearly nothing where it is tacked to a
2.375 in. dia. The end of the cone, in place, is about .375 in above the metering plate.
Most of us with 930's still running CIS S--- can the stock air cleaner for small
cartridge type. This allows more room in a very crowded engine bay. I have
never heard anyone mention any difference in CIS functional operation after
removing the stock air cleaner. This leads me to think the cone has no impact on the metering plate.


I understand what your saying about Bosch and Porsche having the answers. I have a tendancy to agree with Keith in that they designed it for the HP of what it was being installed in, not for a bunch of crazies trying
to wring every last drop of hp out of it. I think the 930 CIS is actually off the old 6.3 Mercedes; if you look they usually have 2 extra injector ports blocked off or plugged. The K Jetronic was used on a lot of different cars
so instead of reinventing the wheel they just retrofited what they already had.

Cole

http://forums.pelicanparts.com/uploa...1236483601.jpg




http://forums.pelicanparts.com/uploa...1236483659.jpg

Cole

Found my old add from when I sold my old what I call at the time "electronic WUR"

http://forums.pelicanparts.com/porsche-911-used-parts-sale-wanted/152629-930-cis-fueler-tuning-w-lap-top-fs.html

Man it worked well: :)

http://forums.pelicanparts.com/uploa...1078861954.jpg

Cole,
The jury is still out on that one. Let's just say the best we could do was agree to disagree. The debates started when the "great" Powerflow air cleaner assembly came out and people were pretty ticked that they were not seeing the HP increases the manufacturer had claimed. There was a lot of speculation back then on what "the cone" was used for. At the very least it redirects and stabilizes the air flow to the metering plate.

That cone is definitely a flow straightening device, as Dave says. Probably directs the airstream out towards the edges of the plate, I would suspect at higher airflow rates.

Looking at some K-Jet literature last night, and being a non-930 guy, I realized what should have been obvious to me: the 930 and SC airflow directions are opposite. 930's flow down, and mine flows up. So, it is a completely different dynamic regarding airflow, but the symptoms and stalling are the same. Hmmm.

[QUOTE=911st;4529644]Found my old add from when I sold my old what I call at the time "electronic WUR"QUOTE]

I really like the idea, but how/where can I get my hands on the custom AIC-1 controller? Since I'm already using the Andial setup, it would be so simple to upgrade it to something more tuneable.
For now, I'll continue with my plans to make the Andial injector react to a combination of boost and rpm delayed enrichment, and look at modifying the duty cycle adjustment (via resistors at the potentiometer) if more enrichment is needed beyond the stock design.

Dave,

Dave I agree with you !!!! I was wrong to have made a definitive "no"
statement. I know from changing air cleaners on my motor I "noticed" no
difference in idle, cruise, or wot. I'm quite sure if you were to flow the CIS
with and without we would know the difference although I never heard
of a unit flow tested with an air cleaner installed.
In retrospect I will reiterate, as with my "Mercedes" statement, I don't
think Porsche would have put it there if I did not serve some functional
purpose. You and Pat are probably right in it being used to direct air, in
some particular manner or pattern, over the metering plate for some
functional purpose I do not Know.

Cole

[QUOTE=mark houghton;4530033]
Just contact Splet Second Timing and ask for an AIC-1 with an internal oscillator so you can fix the frequency instead of having it be a function of rpm.

http://www.splitsec.com/index.html

If they do not understand, contact me and I will give you my name and they can look up my system from 2002.

However, the Digital WUR accomplishes the same thing is has a lot of support and may be easier for most.


As to the Air Filter Cone. There has been much debate with the advent of the ABS replacement that takes a cartridge K&N style filter. No real conclusion was ever reached though one or two seemed fell they lowt something with the change.

It looks to me like it is designed to feel in the low pressure area of a swirl pattern and the above the MP to reduce turbulence. If you look at the overall design, it is not much different in how the watter looks when you flush the toilet.

:)

Cole,
Oh, no, I didn't mean to say I was disagreeing with you in any way. I going back to the time, several years ago, when the Powerflow first came out. I was one of those who purchased the product from IA who was suspecting the unit didn't perform as claimed. I'm with you 100%.

I just can't let the day go by without my 2 cents worth.
I too almost fell for the ABS plastic box "improvement", but instead opted to simply modify a spare stock airbox I had on hand, to accept a huge cone K&N filter. Ended up looking just like the Powerflow unit. Probably all I really benefitted was opening up the engine compartment...and just maybe a little more flow through the K&N. In retrospect, if that cone shaped piece at the end of the box is deemed important for directing airflow across the metering plate, then I guess I got the best of both worlds by keeping the (almost) stock box assembly.