How to convert a 202 to Delco
Posted: Sun Mar 01, 2009 8:21 am
Well i'm sure theres alot of people out there in the same boat as me, driving around with a vk efi engine and just want that little bit more tunability from it!
Even if your car is not a 202 most of the stuff here will be of good use if you want to do it. The first issue and probably deal breaker, is getting a crank trigger, which on some cars is as simple as getting a dizzy from another model or in my case can be a far more custom made option.
That said it is not as hard as you might think to convert alot of dizzy's to work perfectly. So firstly you need to find out what type of dizzy you have and then you can work out which option from the delco stuff you can use to convert it. Theres really two factory options that are easy to use, Hall Effect (VN-VT Commodore) or Reluctor (Carmira/Astra/Pulsar).
In my case the reluctor setup was what was in the standard holden electronic dizzy so thats the route i took with my conversion.
So firstly to do this you need to get your hands on a few parts from bosch:
BIM148 - Bosch Ignition Module
BCS803 - Bosch Pulse Generator
Bosch Ignition Coil (part number TBA)
Now the pulse generator is not mandatory but its only about $15 and it gives you a lead to cut off the camira pulse generator and attach to the end of the 202 dizzy and then will give you a neater finish. Now that we have all the hardware its time to start modifying stuff. I suggest you get a spare 202 electronic dizzy for this as it wont be usable in its old application once modified.
So first thing to do is to start stripping the dizzy down, i figure its worth while fully pulling it down just to give it a good once over and clean and then lube it all up so you know it will work properly! Once you have done that, put the main shaft in the vice, strip all the springs and advance weights from it then weld the bottom part to the top part like in the picture, if you get the two parts in roughly the same spot i have them in the picture it gets the timing mark on the housing VERY close to the right spot (although this doesn't really matter as much anymore)
Now the next bit you need to weld up is the vacuum advance mechanism, you will find when your pulling it apart that there is two allen key screws on the base of it that are exposed when you turn the top section, you need to weld it up so the holes are lined up otherwise you can throw it out! All it needs is a small weld to hold the two sections together. Be careful not too go too hard welding here because theres plenty of bits in it that can be damaged by heat if they get too hot.
with that done its time to start putting the dizzy back together, once you get it to this stage you need to start working out where to mount the ignition module, i have found the best spot is under the base on the side of it, as it allows the heatsink part of the module to fully contact the dizzy base to disipate heat and its reasonably protected aswell.
make sure you apply the heat transfer paste before attaching it and don't be sparing, just blob it all on, you can wipe away any excess that squirts out the sides! You will also notice that the pulse generator lead fits nicely here and makes for a nice neat conversion, plus if the module ever fails its a simple job to replace, requiring no soldering!
About the only other thing you need to know here is that the 202 dizzy has two black wires coming from it, one has a larger lug, this is the positive wire and it needs to be connected to the P terminal on the ignition module and the small lugged wire connects to the N terminal. When its all said and done you should now have a dizzy that looks alot like this and hopefully works just as well
One last point, i have found the best way to re-install the vacuum advance mechanism (after locking it) is to get a piece of thin cardboard or something similar (cut up a coke can if you have one) and it needs to be long enough to go the whole way around the outside of the star trigger wheel in the dizzy, so with the allen key screws loose, slot it in between the inner and outer teeth and then rotate the shaft so the inner and outer teeth are lined up with each other, this should perfectly centre the mechanism at which point you can tighten the two allen key screws.
Once you remove the precision lining up tool you should be able to rotate the dizzy shaft without any of the inner teeth touching the outer teeth.
So the next thing you need to do is get the right sensors on the throttle body .... theres a few ways i've seen to do this, one is by making adaptor plates and brackets to mount suitable sensors onto the standard VK EFI TB ... or the other option which i chose was to graft a VN TB flange onto the VK manifold. While i was at it i welded up a few un-needed holes to neaten it up and re-tapped a new thread into one hole to suit the VN MAT sensor.
So this is the flange, i basically hacked up a VN V6 elbow which was pretty close to perfect for what i needed.
And this is the working product ... mind you i didn't do too good a job of it, its not even straight
also note, left hand end, the hole there has been welded up and smoothed over, and after this picture was taken i welded up the fitting to the right of the TB and then drilled and re-tapped it to suit the VN sensor thread ... unfortunately its bigger than the vn sensor needs and i wasn't able to find an adaptor to allow it to just screw in .... but if your getting a flange welded on its not hard to zap the hole at the same time. Also at the top of the picture there used to be a EGR valve flange on the manifold, these holes were also welded up and smoothed over.
With the manifold completed all that left was to sort out the wiring, and if your like me and unable to get your hands on a camira wiring loom then the other option is to modify a vn v6 loom to suit. This is not a hugely hard task, but does require a few plugs to be sourced from a camira/pulsar/astra .... alternatively if you wish to go all out you can buy them brand new from http://www.eficonnections.com ... and you will need, the two plugs that connect to the ignition module and the two plugs (which join to make one plug) for the ignition coil.
You need to cut the DFI module plug off the VN loom and this provides the wires you need.
This diagram shows what you need to do: VN wiring diagram if you need to reference it for wire colours: For the Pink wire on the coil i used the Red wire that fed the DFI module, and there should also be a green tacho lead there aswell for the brown wire on the camira coil.
As mentioned above, efi connections actually have the wire that goes from the coil to the ignition module pre-made if you prefer this option.
With this all done correctly you should be able to get spark out of the system which in turn will provide the reference pulses for firing the injectors in which case your pretty much ready to go!
Also note that to get all the vn wiring loom in the right location i had to strip back virtually the whole lot and re-route alot of wires to get them where i needed them, but the good thing is there is enough wire in the loom to do it!!
It went from this: To this: Oh and one last thing, i did a comparison of the smallest part of my delco inlet pipe compared to the hole in the vk air flow meter .... i reckon theres a good 30-40% increase in air there! so if there was a restriction there wont be now
If anyone can see parts i have missed or anything you would like added to it etc please let me know and i will update the original post to keep it as one big article!
Even if your car is not a 202 most of the stuff here will be of good use if you want to do it. The first issue and probably deal breaker, is getting a crank trigger, which on some cars is as simple as getting a dizzy from another model or in my case can be a far more custom made option.
That said it is not as hard as you might think to convert alot of dizzy's to work perfectly. So firstly you need to find out what type of dizzy you have and then you can work out which option from the delco stuff you can use to convert it. Theres really two factory options that are easy to use, Hall Effect (VN-VT Commodore) or Reluctor (Carmira/Astra/Pulsar).
In my case the reluctor setup was what was in the standard holden electronic dizzy so thats the route i took with my conversion.
So firstly to do this you need to get your hands on a few parts from bosch:
BIM148 - Bosch Ignition Module
BCS803 - Bosch Pulse Generator
Bosch Ignition Coil (part number TBA)
Now the pulse generator is not mandatory but its only about $15 and it gives you a lead to cut off the camira pulse generator and attach to the end of the 202 dizzy and then will give you a neater finish. Now that we have all the hardware its time to start modifying stuff. I suggest you get a spare 202 electronic dizzy for this as it wont be usable in its old application once modified.
So first thing to do is to start stripping the dizzy down, i figure its worth while fully pulling it down just to give it a good once over and clean and then lube it all up so you know it will work properly! Once you have done that, put the main shaft in the vice, strip all the springs and advance weights from it then weld the bottom part to the top part like in the picture, if you get the two parts in roughly the same spot i have them in the picture it gets the timing mark on the housing VERY close to the right spot (although this doesn't really matter as much anymore)
Now the next bit you need to weld up is the vacuum advance mechanism, you will find when your pulling it apart that there is two allen key screws on the base of it that are exposed when you turn the top section, you need to weld it up so the holes are lined up otherwise you can throw it out! All it needs is a small weld to hold the two sections together. Be careful not too go too hard welding here because theres plenty of bits in it that can be damaged by heat if they get too hot.
with that done its time to start putting the dizzy back together, once you get it to this stage you need to start working out where to mount the ignition module, i have found the best spot is under the base on the side of it, as it allows the heatsink part of the module to fully contact the dizzy base to disipate heat and its reasonably protected aswell.
make sure you apply the heat transfer paste before attaching it and don't be sparing, just blob it all on, you can wipe away any excess that squirts out the sides! You will also notice that the pulse generator lead fits nicely here and makes for a nice neat conversion, plus if the module ever fails its a simple job to replace, requiring no soldering!
About the only other thing you need to know here is that the 202 dizzy has two black wires coming from it, one has a larger lug, this is the positive wire and it needs to be connected to the P terminal on the ignition module and the small lugged wire connects to the N terminal. When its all said and done you should now have a dizzy that looks alot like this and hopefully works just as well
One last point, i have found the best way to re-install the vacuum advance mechanism (after locking it) is to get a piece of thin cardboard or something similar (cut up a coke can if you have one) and it needs to be long enough to go the whole way around the outside of the star trigger wheel in the dizzy, so with the allen key screws loose, slot it in between the inner and outer teeth and then rotate the shaft so the inner and outer teeth are lined up with each other, this should perfectly centre the mechanism at which point you can tighten the two allen key screws.
Once you remove the precision lining up tool you should be able to rotate the dizzy shaft without any of the inner teeth touching the outer teeth.
So the next thing you need to do is get the right sensors on the throttle body .... theres a few ways i've seen to do this, one is by making adaptor plates and brackets to mount suitable sensors onto the standard VK EFI TB ... or the other option which i chose was to graft a VN TB flange onto the VK manifold. While i was at it i welded up a few un-needed holes to neaten it up and re-tapped a new thread into one hole to suit the VN MAT sensor.
So this is the flange, i basically hacked up a VN V6 elbow which was pretty close to perfect for what i needed.
And this is the working product ... mind you i didn't do too good a job of it, its not even straight
also note, left hand end, the hole there has been welded up and smoothed over, and after this picture was taken i welded up the fitting to the right of the TB and then drilled and re-tapped it to suit the VN sensor thread ... unfortunately its bigger than the vn sensor needs and i wasn't able to find an adaptor to allow it to just screw in .... but if your getting a flange welded on its not hard to zap the hole at the same time. Also at the top of the picture there used to be a EGR valve flange on the manifold, these holes were also welded up and smoothed over.
With the manifold completed all that left was to sort out the wiring, and if your like me and unable to get your hands on a camira wiring loom then the other option is to modify a vn v6 loom to suit. This is not a hugely hard task, but does require a few plugs to be sourced from a camira/pulsar/astra .... alternatively if you wish to go all out you can buy them brand new from http://www.eficonnections.com ... and you will need, the two plugs that connect to the ignition module and the two plugs (which join to make one plug) for the ignition coil.
You need to cut the DFI module plug off the VN loom and this provides the wires you need.
This diagram shows what you need to do: VN wiring diagram if you need to reference it for wire colours: For the Pink wire on the coil i used the Red wire that fed the DFI module, and there should also be a green tacho lead there aswell for the brown wire on the camira coil.
As mentioned above, efi connections actually have the wire that goes from the coil to the ignition module pre-made if you prefer this option.
With this all done correctly you should be able to get spark out of the system which in turn will provide the reference pulses for firing the injectors in which case your pretty much ready to go!
Also note that to get all the vn wiring loom in the right location i had to strip back virtually the whole lot and re-route alot of wires to get them where i needed them, but the good thing is there is enough wire in the loom to do it!!
It went from this: To this: Oh and one last thing, i did a comparison of the smallest part of my delco inlet pipe compared to the hole in the vk air flow meter .... i reckon theres a good 30-40% increase in air there! so if there was a restriction there wont be now
If anyone can see parts i have missed or anything you would like added to it etc please let me know and i will update the original post to keep it as one big article!