Thread: Re-wirting engine management 99 disco 3.9.

Amberley autos in Dandenong VIC, have a 4wd dyno, and have the expertese to tune it - they have already quoted me $1250 fully tuned, which seems quite reasonable.

Is there much headroom in the factory 3.9ltr V8 to tune some power & economy into it. Inherantly the biggest problem seems to be with the low 8.2:1 comp ratio, which makes it inefficent with the fuel useage (not much cylinder pressure).

Is it worthwhile to do this - a handy 10-15kw gain, and some improvements to fuel use would be why this would be done. Anyone know what the wide open throttle A/F ratio is? My guess its in the single figures, if so there is ability to run leaner towards 12:1 for std unleaded or as lean as 13:1 if preimum was used.


questions questions. Sorry. [img]style_emoticons/<#EMO_DIR#>/biggrin.gif[/img]

I think the $800 wolf may only tune fuel, if you were going to the trouble of changing the ecu I would want to do timing as ign well.

I think I'll wait until I get the bigger engine !!!

Probably right about the fuel only for the wolf computer. Just an ad. in one of the magazines I used to read but was only thinking economy rather than performance. [img]style_emoticons/<#EMO_DIR#>/biggrin.gif[/img]

Guess it depends on how far he wants to go and how much money he has to spend.

Another thought is has the exhaust been changed :?:

I have wroked on a Wolf 3d fitted to a ser 3 Jag and it does timing but I think it was about $1500. It worked ok but could only be tuned by the hand controler, this takes ages. I think the one that just does fuel is called a 2D. The EMS ones seem to work well and can use the hand controler or lap top. The one I work on is called a "Dual sport," it could hold 2 maps and tuned fuel and ign. You can change the map while running by a toggle swtich on the dash if you enable this option in the set up. The Dual sport is obsolete now and they have new range, I think the new one may be called a Stringer. We tuned this one in one night on a dyno, could have spent more time but weren't worried about ecconomy on this car just power and we left it a bit fat for safty. The engine broke the ring groves out of 7 pistons and cracked the block every where regardless. New engine will be together this week and we will run it on the rollers a again to fine tune. This time I reckon it won't break as quick.

Ooooooooooooooley.
An engine that busts grooves must have had coolant and oil bubbling from under the heads :!: That's the sign of real grunt, although breaking the block completely in half is also a good sign. [img]style_emoticons/<#EMO_DIR#>/biggrin.gif[/img]

Is it worthwhile to do on a std engine - I may slot in a 2.5" exhaust system while im at it, [img]style_emoticons/<#EMO_DIR#>/biggrin.gif[/img]

Probably would make a difference. Personal thing whether it's worth it. [img]style_emoticons/<#EMO_DIR#>/biggrin.gif[/img]

I'm a sucker for dual exhaust note. If you're half handy with a welder, should make your own exhaust up. Made a dual system for mine in a weekend using bits I bought from a wrecker. Cost me $50 and my time to make it. Just be sure both pipes are the same and you shouldn't need a balance pipe between the two to even up exhaust pressure. [img]style_emoticons/<#EMO_DIR#>/biggrin.gif[/img]