Lucas Hot Wire - Which tune resistor?

C

captainbeaky

Active Member

Posts

292

• Apr 11, 2007

• #1

I've dropped a 4.6 engine into my 3.9 classic hotwire.

Just got it running - all is well.

Just wondering - does anyone know what the tune resistor options are?

I know - I know - it's not a perfect set up for fuelling, but the engine will be run on LPG 99 percent of the time, so I'm looking to get it running as best as I can on the current hotwire rather than a 100% perfect setup...

Any info would be useful...

Cheers,

Mike.

 

E

eightinavee

Well-Known Member

Posts

3,956

Location

UK.

• Apr 11, 2007

• #2

Is it still running with oxygen sensors ?

 

C

captainbeaky

Active Member

Posts

292

• Apr 11, 2007

• #3

no - it's a pre-cat car.

 

E

eightinavee

Well-Known Member

Posts

3,956

Location

UK.

• Apr 12, 2007

• #4

Think I'd drill and tap the downpipes and fit oxygen sensors,fit a tune resistor,(uk,Cat equipped one)that will make the Ecu respond to the sensors.That way you wont be running a fixed fuel map for a 3.9. The map for a Cat 3.9 should be able to go rich enough on injector pulse width to cope with the extra air taken in.Then you could prove its being fuelled properly on petrol - and more importantly on LPG.Very important if you want to avoid the head gasket and cracked block issues with 94mm bore V8's.

 

C

captainbeaky

Active Member

Posts

292

• Apr 16, 2007

• #5

Good idea - I'll think about it - what are the options for the tune resistor?

What value resistor does what?

Thanks,

Mike.