Thread: Multiple spark systems (MDS)

Hi Stirlsilver,
The plan is to try it in the V8 Disco with LPG injection

LPG alone has one big benefit, and that is that it has a very high Octane rating. If you are running dual fuel then you have somewhat limited options. BUT, if you chose to run LPG only you can do some cool stuff to your engine to get as much power out of LPG as possible.

Why run LPG only? Well, dual fuel will always be a compromise, each fuel needs its own ignition advance curve so when you run both fuels you can only live with a comprimise. Another thing is that since LPG is 100 octane you can run MUCH higher compression ratios to get more performance out of the fuel.

I don't know if you have seen any of what I have done, but I run about 12:1 compression ratio in my rover v8. It's been some what experiment so far but it certainly does work quite well. This is even on the older mixer ring type system (I could only dream of trying it on LPG injection at this stage).

With such a high compression ratio though you need to get your ignition right (as I found out) and you need a good strong ignition system. Anyway, just some food for thought. If waxen sniffs out this thread at all, he will vouch for the performance of the engine, and when he saw it it was with zero mechanical advance (to be sorted).

Anyway, just something I thought you would be interested in.

Hi Stirling,
Tell me more about strong ignitions?

The gas injection starts on petrol for the first 2-3 min and then flicks over to gas, that is all the petrol driving I do.

MSD-6A and Crane HI6 both are high quality multiple spark units. From what i have read, the Crane may be just slightly better.
However, if you have electronic ignition you will also need an extra item that links the tacho.
Check the following websites for info. There is installation requirements on the sites somewhere but i havent looked at it for a while. Do a google search for install if you cant find it on the sites.

MSD Ignition
CraneCams

Follow the links to the ignition sections.
Also, you might want to contact Rocket Industries as they will be able to advise on what best suits your installation.

Hi BB,

If you really just want a big spark do this:

Outer Limits 4x4 Board :: View topic - Fitting GM HEI to P76 or Rover V8

and make sure you read the responses down the page. I couldn't fit the HEI dizzy because there is not enough room with Chev in a RRC.

cheers, DL

Well I fitted an MSD 6A, Coil, Tacho unit, and new expensive spark plugs. I already had good 8.5mm leads.

So far the power improvment is noticable and the economy seems a bit better, I'll know more when I've done a couple of tank fills.

Thanks 350RRC for the link, only I'd ordered the MSD before hand.

It will be interesting to see how the MSD setup handles a bit of water in the coming weeks as that has always been an issue with the V8.