Isuzu G-series Twin Cam

Hey,

I'm after a MAP (Manifold Air Pressure) sensor for my G180W. I'd prefer something that bolts in to the standard plenum.

Also after a G200W Electronic Dizzy with CAS (Crank Angle Sensor).

I'm also after a few other bits, and I'm not quite sure where to get them, wreckers, Autobarn, second hand etc. Any suggestions would be appreciated.

-Throttle Position Sensor
-Manifold air temp sensor (is this really neccessary?)
-Atmospheric pressure (Barametric pressure) sensor (as above)

Sorry for asking a million questions but the world of EFI is new to me...

The actual MAP sensor from any Delco system using the 808 ECM should do providing you are not boosting. They don't need to attach directly to the manifold. Most are mounted to the body panels and have a vacuum hose connecting them to a barbed fitting on the plenum.

It is possible to run boost with an 808. If you are, you'll need to buy a MAP sensor suited to the boost you plan on running.

That brings up another aspect... boosting requires a bit of tricking to set up as far as the data settings go so the info from the MAP sensor is correctly configured. Stock out of another standard car, the 808 is calibrated to calculate for N/A pressures. For the moment I'm not going to be able to provide the data for boosted setups. Maybe I will in the future.

Thanks Poida, very helpful as always. What should I expect to pay for a standard MAP sensor - just so I don't get ripped off?

I think I'll go and talk to an EFI place about a MAP sensor to suit boost. Autobarn said it was quite complex and it has to be set up just right for the application, or it could give false readings.

Will the Delco run without all of these sensors, or are they required for the engine to turn over?

The Delco will fire an engine up without most sensors but only in limp mode. You need a few basic components then the ECM can calculate the required amount of fuel to inject as required for any air flow quantity and engine load.

Put simply, the JD Camira TBI 1.6 litre engine is a good example of the base requirements to get a reliable setup happening.
The required components are

• Engine Coolant Temp
  Manifold Absolute Pressure
  Throttle Position
  Vehicle Speed
  Barometric Pressure
  Engine Speed
  Crankshaft Position
  System Voltage

You also need switches to indicate if the auto trans is in park or neutral and a switch to indicate the aircon is operating if either of these are fitted.


As for a MAP sensor to suit your needs, find one that will plug directly to the same wiring plugs as the Delco uses but it will need to be a 2 bar MAP switch. You should be fine setting up to that level as factory equipped cars (in UK, Germany and USA) run that type of setup. I'm not sure if you will be able to exceed that 14lb boost level. It isn't something I've yet looked hard into.

Ive heard that CAPPA performance can get the 2 and 3 bar MAP sensors. They are in SA somewhere i think. Google it.

Cheers. Bob.

Thanks. Would the engine speed sensor simply be a connection to the ign. coil like a tacho?

I will read through this when I have more time and am less tired, in the interests of not wasting everyone else's time. I'll edit this post later... Thanks

The engine speed sensor is the distributor and its workings.

Do you mean the vehicle speed sensor???? If your using a Delco the one off a Pulsar/Astra will screw straight onto the isuzu gearbox where the cable comes out. Only drama is you wont be able to put the cable in. I think the Castelmaine Rod Shop or Casltemain Auto Electrics can offer a splitter for the speedo drive (same as a commodore V6 conversion). You need to know what ratios will make the speedo accurate when ordering so you need to do some home work.

Cheers. Bob.

just go to u pull it and have a look pocket what u want then leave


heaps cheap

LOL @ GrampsTD. I might have a look around there.

Yeah, I'd need both engine speed and vehicle speed. I'm still completely lost as to how the computer get's the crank angle signal - I've heard so many conflicting arguments. Is it from an electronic dizzy, like the engine speed signal? Or is it the engine speed signal?

archangel62 wrote:LOL @ GrampsTD. I might have a look around there.

Yeah, I'd need both engine speed and vehicle speed. I'm still completely lost as to how the computer get's the crank angle signal - I've heard so many conflicting arguments. Is it from an electronic dizzy, like the engine speed signal? Or is it the engine speed signal?

There is no such thing as an engine speed signal. Your a naughty boy and dont mention it again. Forget you ever heard it.


There is the vehicle speed sensor.
Visit Pocket a Part wreckers. Ive got two or three here i scored.

Then there is the distributor. That measures where the crank (camshaft) is in its rotation it also happens to send the spark to the plugs.
With the module attached to the distributors wiring the ECU can work out how many RPM the motor is doing if it needs to, which i doubt it does. Its a computer it can work shit out quicker than your feeble mammal brain can.
Bit hard to fit a whole distributor in ya pocket and not have it noticed.

You can use the RB type distributor internals (Reluctor). Or do as im planning and mod the Dizzy off the donor Delco car so it can be mounted and fit onto the distributor drive.

The I-tec twin cam had a Photo electric distributor (internal slotted disc crank angle sensor) and im not sure if the Delco will read the signal it generates with a std memcal.
I is possible that the V6 motor or possibly even the later generation Ecotec would have used a photo electric CAS system of some sort so you may be able to reprogram the Memcal to use the signal. Dont know Poida would have a better idea.

Cheers. Bob.

Thanks for the info. Where is the vehicle speed sensor located? Gearbox?

I'm considering a change of plans (again) so I'll finalise plans when I have the money, that way I can't go back on them.

Got a MAP sensor, 2bar, was free with my MS2 kit!
Got an IAT sensor, off DIYAutotune.com
Don't need BAR sensor anymore

Still gonna have to convert a TPS on, any help would be appreciated but I might have to sus out a wreckers yard, the MS2 can be calibrated to any TPS.

Another method of sensing VIHICLE SPEED is to use an inline speedo cable adapter such as those used in aftermarket cruise control kits. Most off the shelf CC kits offer a basic magnetic sensor and a pair of magnets that you attach to the tailshaft (primative but it works) as well as an option to fit a higher quality inline unit if you want to spend a few more dollars.

The kits I'm familliar with are the AP60 cruise control kits that you find in Autobarn stores.


Now I know the company who import and distribute these kits also sell a neat little inline pulse generator such as is needed for the Gemini speedo cable. It's your best option and worth spending a few dollars on. I'll see if I can find the part number and a price for you.