The V8 Owners Forum -

Hey guys.

Long term Rover driver, but new to the 215/RV8. Just bought into Land Rovers and after buying a complete shed of a 300TDi I've stripped it and am putting the off-road kit onto a '95 3.9 Discovery 1 primarily for green laning.

28, Marlborough West Wiltshire, Electical Engineer working in Swindon.

Unlikely to post much, but I'll be poking about looking for common ailments and doing a bit of research as I'm intending on picking up another 3.9 (or possibly a 4.6, undecided yet) and rebuilding while I run the original 3.9, with the aim to ramp up the low end torque for easier green lane cruising rather than top end hp.

Welcome aboard!

Chris.

Depending on what injection you have, you can usually get a very worthwhile gain at the bottom end by going to mapped wasted spark and mappable injection.

On my SDI, the biggest difference in performance after doing this was to the bottom, not top, end.

It's '95, believe that's pre-motronic, so should be GEMS? Not certain about that in any way shape or form though, as I said, new to the V8s, I'm used to working with MEMS on the T16 Turbos, so basically, not having to do anything at all until you're knocking on the door of 300hp at which point it'll struggle to automatically adjust the fuelling.
Didn't realise there were wasted spark options out there, I've been aware of EDIS8 for a while but haven't looked into it yet, for the moment I'm giving a go to the weird little multi-fingered condom affair to waterproof the ignition, filled with vaseline and liberally sprayed with ignition sealer when all tightened up, but if there's a definite performance bonus to be had by going electronic ignition or wasted spark then that might well be something I can suddenly justify more easily to kill two birds with one stone.

A Disco 1 3.9 will be the Hotwire system.

On those engines, the fuelling and ignition are basically completely separate. So you could go to EDIS8 + MegaJolt Lite Jr and keep the EFi unchanged (there is one connection between the two that I don't know how you sort out though).

Otherwise MegaSquirt will do all of it.

I used EDIS8 on mine for a while, it was excellent.

But for real torque increase, you need more cubes, i.e. a 4.6l bottom end with a suitable cam.

Chris.

Although I'm using EDIS and it works well, I'm not sure I'd use it now if starting again. Disadvantages are things like not having a user adjustable rev limiter. But it is simple to install and reliable.

As regards Megajolt, it works very well. But for more cost you could start off using MegaSquirt ignition only, giving you the choice of using it for the injection later on. You can use MS to drive either EDIS coils or smart units like LS single coil per plug, giving you full control of the ignition under all conditions. With single coils per cylinder you then have the choice of wasted spark or sequential.

Welcome Vard

Perry