The V8 Owners Forum -

Hello everybody!

I'm in the process of rebuilding my Range Rover engine and at moment I'm at the stage where I have to decide what I should be running ignitionwise.

The engine is a 3.5 V8 (obviously ) with a Kent H180 cam and gasflowed heads fed by twin su carbs.

What is the diffrence in the two solutions as title says and which one is the way forward? (I do not intend to go efi in the future.)

Where can I find reliable ignition maps which suit my engine configuration?

Are the ignition kits that both offer complete or are there still several other add-ons which I should keep in mind?

Or should I stay with a dizzy (mallory??????)?

I know, lots of questions but I want to do it right straight away.

Thanks for your help!!!

Regards

JK

It is generally better to make your own map - unless having the whole job done by a tuner.

Someone else's map is unlikely to be correct for your particular modified engine.

With MS, the base map supplied with the firmware will be a good starting point - and errs on the safe side.

I don't know anything about Megajolt but I would have thought MegaSquirt is a bit of an over-kill if you do not want EFI since I feel the whole point of an sophisticated ECU is to control fuel and spark precisely.

May be worth speaking to V8Dev as they fitted Megajolt to a engine they built up for me,


Martyn

How many CDM' do you get out of that Mallory (Condensers per mile)

For me either Megajolt or MS are my top 2. I have run both.

I would base the decision purely on the cost if you really are not going to drive EFI, there's no difference in how the engine will run with either.

Back in the day you used to be able to buy MJ kits, which made it much more cost effective than a MS in spark only.

However! I think that is no longer the case, and so you can probably get an MS kit (if you are happy soldering) for a similar price to a ready built MJ. Please dont take my word for it though, checkout autosportlabs and diyautotune or something for a comparison.


Pro's and Con's of each:

Megajolt:

+ Small
+ Simple to wire up
+ Generally less scary
- Kit used to be surface mounted, so maybe harder to repair in future if a component fails.
- Possible cost
- Restricted to Spark only, no possibility of running fuel at all.

Megasquirt:

+ Kit is cheap
+ Choice of through hole or surface mounted
+ Possibility of doing fuel later if you want...
+ Bigger user base, so more development and more whizzy things (for example my MS connects to my phone via bluetooth which is quite handy if you just want to see what is going on)
+ More inputs/ outputs to do fancy things with.
- More work in building a kit than MJ used to be.
- Bigger case (not a problem in a Rangy though)
- Seems more complicated than MJ, its not really though

I remember the first time my 90 fired up on EDIS, the difference from the dizzy was noticeable, and it didnt run bad with the dizzy!