Steve Dunford

It runs! Turns out its an even fire engine after all - and the one item I re-used from the old setup was a dodgy relay which was cutting power to the ignition circuit intermittently which caused me some grief for a few hours. Once that was sorted I managed to get it cranking with a little help from a tin of brakleen Tweaked the fuel map a little and played with the accel enrichment and managed to get it idling and revving pretty cleanly. Its just getting some tidying up done on the exhaust and a few other things then its off to the dyno for a full tune. It was very cool to be able to make minute adjustments to the tune and instantly see the results at the engine, and it taught me a lot about the way EFI works... If done plenty of engine transplants before both carb and EFI but this was probably the single biggest learning curve I've had in that area... thanks for the support and I'll post again once I get some more pics and a startup vid on the page above. Steve

Thanks for that - I'll try those changes and give you a call today if it doesn't work - I'll also post my results for informations sake and update that pic/info page above when I get time... I'm starting to think a $500 NV commodore with a ready-made 3.8 EFI donk would have been a far better call but hey, this is learning I guess... And no, I've done some more reading and I'm not sure if its even- or odd-fire now so I'll check the cap to be sure... if you can't do odd-fire with the G3 then why does it have an odd-fire mode? Surely with a sync pulse you could do it? It would require a cam position sensor I guess but it should be doable... Not that I want to, but just thinking out loud... Cheers again for the help Steve

Something else I have just discovered with a little research on the web is that this is an odd-fire engine - I found the details here: http://home.off-road.com/~merls_garage/oddfire.html - seems its an old Jeep (Buick) 225ci odd-fire V6 So I'll change that in the config among other things

Oh, and I've set the ignition mode to distributor with rising edge dwell. I'll upload the setup file as it stands to the link above just in case someone can work out where I am going wrong. Cheers

Ok, Its all wired. To recap, its a basic old V6 chev with an electronic dizzy and inbuilt single coil in the cap - as per the above advice I have removed the internal ignitor and have wired the G3's trigger 1 directly to the reluctor (6 pulses per revolution). In PCLink i've set the trigger mode to multi-tooth, with cam as the location and a tooth count of 6 (Sync pulse crank, but does this do anything since there is no sync pulse?) I seem to be getting pulses from the reluctor pickup in the dizzy, as when I go to the triggers tab in PCLink Trig1 signal changes from no to yes during cranking. Changing the filtering level doen't seem to make any difference to that. I have a VL Commodore ignitor, not a mitsi one as I thought was being supplied. It seems to be working, as when I use PCLinks test-mode with a light wired between +12V and the output it pulses away happily. What I just can't seem to get is the ignitor to do anything during cranking, and it doesn't appear the injectors are firing during cranking either (they both work individually and pulse away happily squirting fuel in test mode). Can anyone shed some light on what I might be missing or what I might be getting wrong? I'm just heading back to try changing the polarity of the reluctor in the dizzy, just in case thats what I've got wrong - although I had set my analogue multimeter to mV and I was getting positive pulses when the dizzy was rotated, so I don't think thats going to be it... Cheers in advance for any advice Steve

Yep, it will be going for a dyno tune once the engine is running... I realise the importance of that step I've picked up an ignitor and will get it all wired up today hopefully... and I guess from your comments that I can just try the pickup from the dizzy both ways around and see what one runs stable. I assume it creates a pulse as the arm passes it? Am I looking for a positive or negative pulse if so, and will I see the pulse on an analog multimeter or will I need a scope? Sorry for the n00b questions, I have an electronics background (albeit a long time back) but this is my first link and I'm learning as I go. If there is a more appropriate place to ask these questions, please tell me too... I don't want to be cluttering up the forums with this stuff if its not appropriate. Cheers Steve

Thanks Ashley, I have ordered a new Mitsi ignitor through the local auto sparky as you guys are out of stock, and will hopefully get it all wired up ready to fire later this week. Any easy way to know which wire is which (polarity wise) on the sensor? I'm going to assume white/red is the signal and white is the ground... but knowing my luck that will be wrong Also, just ballasting the injectors - because of the existing wiring I'm going to put the ballast resistors in-line with the injector feeds from the computer - the manual shows 1R 25W, is that still suitable where there is only one injector per feed from the comp? Cheers Steve

Ok, here are the pics - I'm pleased its not points, and I'm hoping the electronic pickup can be tapped in some way to fire the injectors - any advice or help will be gratefully received and I'm sure we can arrange a short co-pilot session in exchange for the advice The three-wire plug out of the base of the dizzy plugs into the cap at the top, and there are two other terminals labelled "Batt" and "Tach" - so wiring it up to run normally would be a breeze... I'm wondering if the "tach" signal can be used, or if its just directly connected to the -ve of the coil... http://www.4wdstuff.co.nz/node/32 By the way - there are 2 separate TPS's on this throttle body (its off some sort of Ford, not sure what) - is that common? I'm wondering why it has a spare... Cheers in advance Steve

Yes, the injectors are somewhere between 1.9 and 2.2 ohm, so I will be fitting a ballast resistor - although being that they are on the borderline in that 2 ohm region does it matter if I use 2.2 or 4.7? Is there a preference for the computer? I will take a few pics of the dizzy today and post them on my site with a link. Thanks for the advice Steve

This one is an old Chev V6 of unknown origin, and the project has kinda fallen into my lap. I've read Bruces thread and was going to jump in on it but theres nothing worse than a thread hijack, so here is my one... What I have is the engine, which was running a carb quite happily, but as its going to be used in winch challenge competitions there was the idea to put a ford throttle body on it instead, which has two injectors above the butterflys. This is purely to give it stable running on stupid angles... personally I would have fitted a cheap old LPG kit and been done with it - but the owner has bought all the gear and its all fitted physically now so onwards and upwards we go. So far he has the LinkG3, an air temp sensor, a water temp sensor and thats about as far as he got. I'm now trying to nut out the quickest, and the easiest way to get it running - and also the best way (just in case thats quick and easy too The distributor is a standard one with a coil built into to top of the cap, and thats about as tech as the engine gets - and this is where I started to wonder just how the computer was going to know when to fire the injectors... Also the distributor - did I read that this will cause running problems? Would it be easy to convert the dizzy system to a coil pack / ignitor one? Any ideas or help much appreciated - I'd like to get this one sorted and running because a: its my first Link, and I quite like what I've seen and read so far, and b: it has a winch comp to be running for in a few weeks... Cheers Steve Dunford 4WD Stuff