Stefan_Nymoen Posted March 16, 2011 Share Posted March 16, 2011 Hi, I'm new to this forum. I have a 89 110 V8. Originally sold to Saudi Arabia, then imported to Norway. It has been modified a bit since then. It has now installed a 4.2 motor and Auto from a RR LSE. And has a megajolt installed. Does anybody has a good MAP for a 4.2 V8. Or what can I do to a 3,9 V8 MAP file, to get it "right" for a 4,2. This engine has been running LPG, but I run only petrol. I currently use the LPG map. Also I'm now running a 4 barrel carb, but thinking of installing MS, but wan't the ignition better first. Does anybody has any pointers?? Thanks, Stefan Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted March 16, 2011 Share Posted March 16, 2011 A 3.9 can run more advance than a 4.2, in fact the bigger the engine the less WOT Spark is needed. One option is to hang on and see what comes on to this thread from the Megajolt users, here the other is to take a screen dump of the spark map you have and post it up in here #and I will have a lookie at it for you, and give you some more apprpraite numbers. Nige Quote Link to comment Share on other sites More sharing options...
Quagmire Posted March 16, 2011 Share Posted March 16, 2011 Would love to help, but my maps are all for a teeny little 3.5 so have more advance. Be careful running the LPG map on Petrol, it *should* have a lot more advance and could do some damage. Quote Link to comment Share on other sites More sharing options...
Stefan_Nymoen Posted March 16, 2011 Author Share Posted March 16, 2011 Ok thanks. I will take a screen dump from the one I'm running now later tonight when I get home from work. What kind of damage are we talking about then? I have no problems with the engine now, and don't drive the car that much. So hopefully I haven't damaged anything.. Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted March 16, 2011 Share Posted March 16, 2011 Ok thanks. I will take a screen dump from the one I'm running now later tonight when I get home from work. What kind of damage are we talking about then? I have no problems with the engine now, and don't drive the car that much. So hopefully I haven't damaged anything.. Depends on what t5he map is If its a PETROL Spark map (prob) and you use it on LPG it will feel "Flat" as LPG required more advance. If the MAP is a LPG Higher spark MAP - and you run this on petrol, then you will have far too much advance, which causes detonation issues and ultimately can burn holes in the tops of your pistons etc etc Most likley you'l have a Petrol map, and from some of the maps that have come past my eyes over the years often designed by Stevie Wonder and Forest Gump Tuning Services having shared a bottle of something Post up Nige Quote Link to comment Share on other sites More sharing options...
Stefan_Nymoen Posted March 16, 2011 Author Share Posted March 16, 2011 This is the MAP I am currently running(I think... This came with the car... As I have read, the values are way to high.. So I have created a new MAP some time ago, but not tried it yet... This is the car I have by the way.. Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted March 16, 2011 Share Posted March 16, 2011 Hiya Ooops ! Yes original map is too advanced, but so is yours now, esp at the lower ends, and soft at the higher RPMs ! I have enclosed a copy of a 4.2 spark map I use as a "Starting Point" on any 4.2, these engines being long strokem have a maximum advance requirement at WOT of 31 @ 3900-4000 RPM and above. Note that the MJ and MS tables are back to front, takes a moment or more for your mind to sort it out Once properly set up then my table can be improved upon, but many customers just take it as it is and are happy with it The "Drop" on yours at V High rpm is prob a bodgey attempt at a rev limiter, - do not do this, partly as itv is not regarded by many who know more than me as a good way to do it, and not nice for the engine, but also that the cell values interpolate - so you don't get a true 30 anyway ! 35 in the prior cells is as I mention above about 4 too much anywaty ! Hope this helps Nige Quote Link to comment Share on other sites More sharing options...
Stefan_Nymoen Posted March 16, 2011 Author Share Posted March 16, 2011 Ok. Thanks If I understood you correct the MAP for my MJ will look something like this.. I have changed some parameters as I only have 10 bins. I'll try it out tomorrow, if I got it correct. Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted March 16, 2011 Share Posted March 16, 2011 Much Beter Let us all know Nige Quote Link to comment Share on other sites More sharing options...
Stefan_Nymoen Posted March 16, 2011 Author Share Posted March 16, 2011 Thanks for the help. Will let you know as soon as I try it Quote Link to comment Share on other sites More sharing options...
Stefan_Nymoen Posted March 17, 2011 Author Share Posted March 17, 2011 I tried it today. It work just fine. Haven't done any extensive testing yet, but worked fine and happy if it's better for the engine. Thanks again. Quote Link to comment Share on other sites More sharing options...
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