CIS to EFI kit

[tbitz]

Originally posted by EdT82SC
Hey Tony,

Will this system be CARB legal? Does it result in reduced emissions? Is anyone planning to put their car on a dyno so we can see how much of a performance gain is achieved?

No CARBs, this is EFI

Sorry, I have no idea what is required to be CARB legal, I live in Canada.

[1fastredsc]

If it's sequential or semi-sequential it should reduce emissions at idle assuming you tune it correctly.

[Porsche_monkey]

Any pricing on the assembled megasquirt board only? (CDN$$$)

If someone wants to post info on stacks I will look into having them CNC'ed in my shop....

[tbitz]

Pricing on the assembled Megasquirt is $299US + shipping (money order only. I can accept paypal if you pay for the fees $10)

[tbitz]

I've been asked about the relay board and if it is required. The answer is no.

I'm not running with one, and I think it makes it more complicated and more things to fail. Also on the 911 it really doesn't add much value. Here is why:

The relay board includes a relay for the fuel pump, and a relay for the fast idle solenoid. The fuel pump relay already exists on the 911, and the stock 911 Aux Air Regulator is used for fast idle. So both relays are useless. You also need to make a custom harnes between the relay board and MS. This adds fabrication time and cost.

For the above reasons, I will not be supplying the relay board with my kit. I think it's better to just route the cables directly to the Megasquirt.

If you insist on having one then you can make it yourself. Note that the intent is to have the relay board in the engine bay and the Megasquirt unit in the cabin. So make sure the cable between the two is long enough and you need to run it BEFORE you solderup the DB37 connector, otherwise you'll have to punch a very large hole in the frame to get the DB37 connector through.

Cheers,

Tony

[tbitz]

I sent my custom Megasquirt load (uses MAP instead of TPS for acceleration enrichement) to a fellow in CAL who already had MS installed in his 911, but was having problems with his TPS sensor. The sensor was causing false triggering and as a result he could not use it for acceleration enrichement. Without acceleration enrichement he was experiencing some lag when the engine was cold.

Here are the spec on this car:
-motor is 78 case 98mm x74.4mm
-11.0 to 1 comp.
-42mm intake port 37mm ex port.
- GT-2 evo cams 485intake lift 464ex. 112 lobe center 20 overlap.
-64mm throttle plate.
-twin plug.
-injectors are 40lb low imp

He installed my Megasquirt load and results are there is now no lag and no flat spots! This is great news as it proves the theory. From the above engine specs you can see this is a fairly aggressive CAM with an oversized throttle body.

[tbitz]

I have also spent some time getting some web hosting and putting together a basic web page. The address is here:



I have also started a yahoo group to discuss implementation details of the conversion. People will be able to upload VE tables and pictures of there setups. It's a good way to exchange info that is specific to the CIS to EFI conversion. I will continue to keep this thread updated with the latest news on the kit, but those who are interested in the kit should subscribe to the yahoo group:



Cheers,

Tony

[Elombard]

Wow - great news!

[aigel]

Tony:

Great engineering work!

Here a few questions that I have and that many others may ask ...

1.) The CIS equipped cars in California are roughly 1974-83. Under current rules, only 74 is smog exempt. With the 30 year exemption, every year, you can expect about 10% of the stock CIS equipped vehicles to join your smog worry free CA customer base. That may be too slow!

With a ton of 911 people in CA, you may want to see if a vehicle equipped with your kit could pass smog. It may look 'wrong' but there are many 911 untrained smog techs that may not know the difference, especially if the stock air cleaner still is on there instead of a billet aluminum 'bitz-racing' air cleaner. Maybe you should change the name to BLITZ RENNSPORT. You know that Blitz means Lightning in German?

2) I realize you are at a very early stage still, but when have you planned to bring your car to the dyno to test it for performance? Nobody will spend even $500 for better startup, idling and seat of the pants feel. People going away from CIS do it to go faster on the street and more so to race! I think it will be really important that you can proof that the kit gives the option to up the power significantly, beyond the usual 964 cam improvement people can get with just the CIS.

4) Can you proof your TPS elimination on the dyno? I think it will worry people. A pressure signal may not build as quickly as the tps can feel. I know your plot showed the graphs pretty identical, but there is a lag between the TPS and the pressure sensor. WHAT IS THE SCALE on the X axis? Please let me know and plot a zoom into one or two of those peaks!

Looking forward to see your kit come together. This must be much more fun than going to work every day.

Cheers, George

[beepbeep]

CIS doesn't have TPS either :-) You open the throttle and wait for (mechanical) plunger to go down and allow more fuel to enter the engine. some people like the smooth feel of it, some don't.

I would certainly like some accelleration enrichening circuitry...

[jhelgesen]

I've been working on a new airbox for my MS project to keep from hacking up a good cis box. This would be made specifically for a MS installation with only the throttle body mount and the intake runners. Will be either aluminum or stainless. I'll post a 3d CAD pic soon. It would also allow the use of more than just the 911 throttle body, I planned on using a Ford on mine with a TPS.

Would anyone else be interested in one?

[tbitz]

aigel,

1) I think in terms of emisions, it would be significantly better than CIS. Considering it uses a heated O2 sensor in "closed loop". Also since you have complete control of tuning, you could have an "emissions" profile you download just before the test, and then you can download your "power" profile as you leave the testing station

2) I don't have dyno numbers now, but I will get some. I would have to put all the CIS stuff back on my car to get a before dyno. This maybe a PITA but I will do it, to show the gains. Perhaps, folks buying the kit can do a before and after dyno run. There will be gains that is for sure.

4) Nothing to see on a dyno for TPS elimination. You turn off the feature and you see the lag of the engine when you floor it. Turn it on and the lag is gone. The scale on the graph is in 0.05 seconds (multiply x-axis by scaling factor).

[konish]

John,
Sounds awesome...keep us posted!

R/
Dustin

[1980 911 sc]

I just saw your partial kit on your webpage. WOW! I am very happy with what I am seeing! Keep it up.

A questino if I get teh partial kit, what will I need to do to complete it? buy injectors, prepare a wire harness, and fabricate a Throttle body (or can I keep using the existing airbox?).....that it?

should I just buy big injectors now? if I intend to boost (turbo or SC) later? what kind do you recommend?

[aigel]

Originally posted by beepbeep
CIS doesn't have TPS either :-) You open the throttle and wait for (mechanical) plunger to go down and allow more fuel to enter the engine. some people like the smooth feel of it, some don't.

I would certainly like some accelleration enrichening circuitry...

I want to see the 911 driver that enjoys the 'smooth' feel of the CIS lag. Even less than half a second will feel like an eternity. The CIS isn't bad overall, but that lag is exaclty one of it's main problems if you compare it to an MFI or carbureted car, where power seems instant, where you feel your kicked by a mule. I would not spend a penny on an EFI kit, if it can't produce that. It not only is fun, but will get you better times in racing...

George

[aigel]

Originally posted by tbitz

4) Nothing to see on a dyno for TPS elimination. You turn off the feature and you see the lag of the engine when you floor it. Turn it on and the lag is gone. The scale on the graph is in 0.05 seconds (multiply x-axis by scaling factor).

I don't understand. If the axis is 0.05 seconds per entry, you may have half a second of lag time there between TPS and pressure sensor! Can you measure the lag time in your graph? Send me the raw (pm first) file if you wish and i can plot it better...

George

[tbitz]

Originally posted by aigel
I don't understand. If the axis is 0.05 seconds per entry, you may have half a second of lag time there between TPS and pressure sensor! Can you measure the lag time in your graph? Send me the raw (pm first) file if you wish and i can plot it better...

George

Time moves left to right on the graph (not right to left). If you look at the rising edge of the blue line (TPS) a rising edge of the pink line (MAP) occurs instantly (no lag). Upon releasing the pedal the TPS goes to zero quickly and the MAP lags, but this of no relevance to acceleration, it is deceleration.

Here is some data from the graph:
MAP is in Kpa, and TPS in % movement.

MAP TPS
33 15
33 15
33 15
33 15
33 16
44 55
95 77
96 77
95 64
83 33
54 15
32 15
24 15
21 15
22 15

[tbitz]

Originally posted by 1980 911 sc
I just saw your partial kit on your webpage. WOW! I am very happy with what I am seeing! Keep it up.

A questino if I get teh partial kit, what will I need to do to complete it? buy injectors, prepare a wire harness, and fabricate a Throttle body (or can I keep using the existing airbox?).....that it?

should I just buy big injectors now? if I intend to boost (turbo or SC) later? what kind do you recommend?

You'll need all the sensors, wiring harness, conectors, injectors, O2 sensor, pressure regulator, etc... I'll try and update my web page with the exact info that is needed to complete the partial kit.

I will supply the first five proto kits with 30lbs/hr injectors. I will be dialing back the fuel pressure to 2.5bar for the NA engine to make the injectors actually flow 27lbs/hr. This way injector pulse widths are not too small at idle. Once folks go to turbo, pressure can be bumped back up to 3bar to get that extra flow that maybe needed (TBD).

[tbitz]

All work and no play makes Jack a dull boy....

Got a hold of some 3D CAD software. Here is what I came up with for the fuel rail mounting bracket.

Now let's see how much it's gonna cost to fabricate it.

[tbitz]

I started working on a "installation guide" for the kit. In order to take some pictures of the wiring, I ended up ripping out all my original wiring and re doing it again. I also did it so that my car has the color coded wiring harness I will be providing in the kit.

I also mounted the new fuel rails and plumbed the fuel lines as they will be done in the kit. I've run the car in the garage a few times and it runs fine. I'm itching to take her for a spin, but it is still very much winter here.

Here is a picture of the new engine bay. In the kit I will assume people will keep the CIS look. By this I mean, the stock air filter will be used and the airbox will not be hacked up like I did. If you want to hackup the airbox, then you will need to source an air filter, and 90degree boot. I will come up with an airfilter option in the future.