Blue V8 dizzy big cap to small cap conversion.

[MAGP]

I am about to refit my old big cap dizzy to my Blue V8 but the big cap will get in the way of various things. I know I can fit Ford V8 cap and rotor to it to get the small cap and it will work but I don't know what ones. I know, or at least I am pretty sure, some of you will know what parts I need. TIA.

[brindo]

I had to do this years ago but can’t remember exactly what model Falcon cap and rotor I used. I do remember that I rang ICE at the time and they gave me the part numbers. Does the VN cap and rotor fit at all or completely different?

[MAGP]

I haven't tried a VN cap and rotor but I remember reading somewhere they don't work for some reason. I could probably just fit a complete VN dizzy and then everything would be brand new but I'd like to see if the Ford cap and rotor works cause it's a much cheaper option right now.

[VZ1_60]

XD/XE V8 cap and rotor ....

Try these numbers and see how they fit:
GB 786 rotor
GB 926 cap
Bosch numbers.

I've done the swap on my VK, no issues.

cheers, John

[MAGP]

Thanks VZ1_60, I will get them tomorrow.
Cheers

[HQ355]

I'd close up the plug gaps a bit as well, the only reason Holden went big cap was to stop cross firing when they opened up the gaps to get them through emissions testing. Just run XD-XE gaps, same dizzy

[MAGP]

I do that with most electronic ignitions. I've never seen any benefit to running large gaps.

[Holden202T]

yep that's right, the XD/XE ones I have used on a blue motor dizzy convertered to camira ignition module and using that in a 304 in the Bedford!

I can't remember what the part number was but there is basically the same cap with male plugs on it, that might be the one you want to suit the big cap leads ?

[vlt304]

I do that with most electronic ignitions. I've never seen any benefit to running large gaps.

i once put the wrong plugs in my vl (vt roller cam engine 808 ecu) rite part number smaller gap and it was stumbling like it had way too much timing no ping just a hell stumble at 2-3000rpm pulled fine under load just on cruse or a free rev hold. this was before i found this site and 1 of the reasons i found it. i changed coil ignition module dizzy map sensor tps coolant temp sensor you name it all for a small plug gap. put the rite plug gap in and all was sweet talk about a head fuck. turns out some ignition systems can be fussy to gap and the holden v8 is 1 of them.

[MAGP]

EFI Holden V8 doesn't need more than 1 mm plug gap. I have a VT roller and run it on LPG and petrol without problems on either. If an ignition related problem is going to show up it will show on LPG before it shows on petrol. My VS (admittedly a V6) was a dog on LPG 4 weeks ago on my trip to Cessnock, switched to petrol and it was ok, driving back home and it started to be a dog on petrol. Coil was giving up, sent it to The1 and he posted about it the other day.
Carby Holden V8 (which this thread is about) also doesn't need more than 1mm plug gap.