CIS to EFI kit

[wreckah]

it would not like the heat either i would think. Same thing goes for the controller for the wideband...doesn't belong in the engine compartment.

[safe]

Originally Posted by wreckah

it would not like the heat either i would think. Same thing goes for the controller for the wideband...doesn't belong in the engine compartment.

Engine bay temperature is ambient, not a problem.
If you place the ECU high on the firewall its also pretty dry.

I got my non-sealed Emerald ECU in the engine bay, had it there for 10 years with no problems. Actually had it apart last year, no sign of corrosion.

My Innovate WB is also located in the engine bay.

[gsmith660]

The cable isnt long enough to get the controller out of the bonnet

[MadeofOak]

Thinking of taking the leap. Is there a way to add electronic ignition to this kit as well? Would be the complete picture.

And what do I look for if I'm buying a 'used' kit? I want to make this leap but I'm a bit worried.

[gsmith660]

You have to modify the stock Bitz kit to upload MS extra to the processor its not hard easy search to find the directions on the internet then you can use EDIS ignition on the 911 and get rid of the dizzy. Good places to get parts are here https://www.diyautotune.com/ and here https://www.clewett.com/

[djb_rh]

Alright, a warning...I haven't read much of the thread. And I didn't do a conversion...I bought one already done. I bought this car:

https://bringatrailer.com/listing/1969-porsche-912-21/

I post this simply because there's some description as well as pics of the engine bay and such, not to start a debate on what I spent how much money on.

Anyway, the main ECU is under the drivers seat and easily accessible. Car starts easily when cold. Power delivery when driving is good. Idle has a pulsing to it, though, that seems like it isn't right. It's not horrible, but it's not right. What's worse is we had a significant warm-start problem this evening. It was parked pretty well warmed up. Sat maybe five minutes. Started it again, but I think the combination of the surging idle with an ill timed clutch release (plus I'm just not used to the clutch yet...it engages really close to the firewall) caused me to kill it. Then it would not re-fire. Fuel pump is running, pressure looked good, VERY strong turn-over. Just no fire.

Let it sit 90 minutes and it started up like a champ.

Any suggestions on what this warm-start problem likely is? Also, suggestions on the surging idle? I really don't have much info on how it was tuned or what the experience level of the original tuner is. I am NOT well versed in tuning, but I am very comfortable with a PC, anyway. I'm smart enough not to change ANYTHING until I know I have the current config well backed up, at least.

So, pointers?


--Donnie

[tirwin]

Not knowing anything about how your system is set up, I can only make generalizations.

It’s likely either fuel or spark.

When CIS cars exhibit this problem it can be a faulty fuel pump check valve or fuel accumulator. Doubt you have an accumulator but maybe a check valve. You likely have some kind of fuel pressure regulator. Maybe that gives you some ideas on where to start on fuel delivery.

The failure mode of some ignition systems is heat related. They fail when hot and work when cooled off enough. You’ll need some way to check for spark when it’s hot.

[wreckah]

you might have simply flooded it.

surging idle probably means too rich, and maybe combined with too rich starting fueling (and maybe combined with a couple of turns of the key?) = flooded.

easy way too know: pull out the fuse for the fuel pump and crank it again...should fire up pretty quickly (and die pretty quickly too of course)

[safe]

Originally Posted by wreckah

you might have simply flooded it.

Surging idle probably means too rich, and maybe combined with too rich starting fueling (and maybe combined with a couple of turns of the key?) = flooded.

Easy way too know: Pull out the fuse for the fuel pump and crank it again...should fire up pretty quickly (and die pretty quickly too of course)

+1

[wreckah]

Donnie, very cool car BTW!

read up on megasquirt, you will learn alot and you will be able to identify issues more easily.

for example: in the startup phase, the MS controller does a couple of things:

- turn on the key (without cranking): it squirt a set amount of fuel (independant of temp) (priming pulsewidth)
- cranking: dependant of temp, it again squirts extra fuel. you set the values for -40°C and +77°C...and the system interpolates in between.
- once the engine cathces, the system enriches some more during the first 250 or so revolutions (afterstart enrichment)

then you also have the WUE (which shouldn't do anything with proper hot starts) andof course the general VE table.

so you have to set these values so the engine starts nicely when icecold, in different temps, and of course also when hot. This takes plenty of attempts to get right. The stock bitz settings will get you in the ballpark.

When experimenting, i flooded the car more than once with too rich startup settings. We have quite a broad temp range here in Belgium (-7°C to + 30°C) and i drive throughout the year, so i want all my starts to be spot on. Almost there :-) I've gotten to the point where the car ALWAYS starts first key, but still have tiny things to improve when driving away. It's detail stuff though...the bitz kit makes you wanna tune your engine to 2018 startability/driveability. ;-)

[djb_rh]

Thanks, folks. So with the fuel pump fuse pulled, if it’s flooded it should then start. Then probably die quickly. But that will have cleared the flooded condition, so reinstall fuse and it should then start again?

Thanks for all the other info. Time to start playing!


—Donnie

[wreckah]

yapp, when cranking, you get rid of the overload of fuel, and when there's only vapors left, then the engine should catch (and die shortly after).

after that, put back the fuse, and your engine should start as normal.

[trond]

wreckah; good quick summary. what would be typical numbers on priming and on cranking ?
My car is hard to start, and I lost track of where i was and where I went. Especially it's been hard to start after I increased capacity and went twin spark

- turn on the key (without cranking): it squirt a set amount of fuel (independant of temp) (priming pulsewidth)
- cranking: dependant of temp, it again squirts extra fuel. you set the values for -40°C and +77°C...and the system interpolates in between.
- once the engine cathces, the system enriches some more during the first 250 or so revolutions (afterstart enrichment)

[timmy2]

One trick to remember is the EFI will usually start when flooded by flooring the accelerator and cranking it over. (Like some old cars would.)
I had to do this a few times when setting up my system years ago.

[wreckah]

yes, sometimes that will work

my numbers, but i don't know how well they would work in other cars, especially twin spark etc...

prime: 5
crank -40°: 18
crank +77°C: 2

afterstark 60% at 250 revolutions

[wreckah]

bitz numbers:
5
10
2

50 %
250

[djb_rh]

Seems like 70% at 250 for the afterstart and then the biggy was 2.5 on the +77*C. Unsure on the cold start number since I haven't played with that yet. I do believe it was getting flooded and thus increasing the hot crank number helped. For some reason I think it was at 1 when I started. No amount of additional throttle seemed to help clear it with the initial settings, that's for sure.

Thanks for the help so far.


--Donnie

[JLW]

I’m considering installing the kit in mt 78 Targa and I’m trying to do all the research pryer to buying. That being said, I have not been able to find the yahoo group forum for bitzracing. Could one one post the link please.
Thanks James

[timmy2]

You need to contact Tony to join.
Home | BitzRacing
Group is here:
https://groups.yahoo.com/neo/groups/bitzracing/info?guccounter=1

[tbitz]

Originally Posted by timmy2

One trick to remember is the EFI will usually start when flooded by flooring the accelerator and cranking it over. (Like some old cars would.)
I had to do this a few times when setting up my system years ago.

Yes, this works well to get out of a flooded situation without having to get out of the car and pull the fuel pump fuse, or wait a long time for the fuel to evaporate.

During cranking, the ECU squirts a fixed amount of fuel, so going wide open throttle during cranking does not result in more fuel, just more air. The result is with WOT during cranking you end up with a much leaner mixture.