Adjustable flapper ECU

[pwd95]

Got this in my 450.



Haven't touched it yet, just wondering if anyone knew anything about them. Thanks in advance

[adam quantrill]

I've got one of them, on mine the knob goes up to '11' for extra power.

;^)

Nah but seriously, the knob is probably to adjust the mixture or fuelling.

[gsx600]

I reckon it's a hoax, someone stuck it on too make it look like it could get 350 hp or it came from a 350

Wedgie would know

[digga951]

You mean a 350i doesn't have 350bhp??? Well b*gger me! After all these years of thinking thats what the model number meant... Next youre gonna be telling me that the Speed "6" engine is mis-labelled too ;-)

[rev-erend]

digga951 said:

You mean a 350i doesn't have 350bhp??? Well b*gger me! After all these years of thinking thats what the model number meant... Next youre gonna be telling me that the Speed "6" engine is mis-labelled too ;-)

Yes - I could not get 6th in my speed 6

[digga951]

[/quote]

Yes - I could not get 6th in my speed 6 [/quote]

Try "R" instead - apparently that means "Race" and is best kept for when youre going really fast... :-P

[wedg1e]

The most unusual one I have has an extra PCB inside badged by Sprintex and from a Range Rover... believed to be a supercharged version from '89.

[pwd95]

The only thing that seems to want to moove is this switch. Sensible answers on a postcard please.....or here if its easier

[leorest]

pwd95 said:

The only thing that seems to want to moove is this switch. Sensible answers on a postcard please.....or here if its easier

Isn't the "switch" a lock for your adjustable knob? Stops vibrations adjusting your adjuster.
Leo

[pwd95]

5 mins... i'll just try that.........

[pwd95]

Right enough....hope I havent adjusted things too much, just twiddled the knob a little bit back and fourth. What does this knob alter then? anyone know?

[leorest]

pwd95 said:

Right enough....hope I havent adjusted things too much, just twiddled the knob a little bit back and fourth. What does this knob alter then? anyone know?

It's probably a multi turn pot so you'll not have made a significant change. Well that's exhausted my knowledge.

[pwd95]

that's a little bit more than me then.

[gsx600]

I would say you probably need a co meter up the exhaust while you turn it, might be for emissions ? making it leaner or richer ?

Undo the top plate and see if it is actually attached to a board

[TVRleigh]

Ask Mark Adams as he used to fit these. not sure if her still does.

[chunder]

I would hazard a guess the pot adjusts the resistance the ecu see's from the air temp sensor (or possibly the coolant temp sensor) and therefore has a slight effect on fuelling loads.

You can actually buy pots like it on Ebay - labelled of course as providing an extra 30bhp !

All it would do is make the ecu see a cooler inlet charge therefore increasing the injector open time slightly.

You can get the same effect for free if you have an adjustable fuel pressure regulator by increasing the pressure a couple of psi.

Of course I could be totally wrong and this could be the nitrous on time adjuster !

[jchase]

I reckon there are only two sensible possibilities for this pot.

1) it adjusts basic fuelling of air mass to fuel to compensate for the fuel pressure regulator being a bit out. Same is carb jetting.

2) it adjusts the window of authority on the throttle pot speed enrichment. Same as adjusting carb power valve.

1) would need a co meter, and 2) would need a rolling road.

Or maybe it does bu**er all!

-Jim

[TVRleigh]

I know the flapper cars did not have a rev limiter, but you could get a mod'ed ECU and that could inc a rev limiter. and I think the rev limiter was adjustable.

[adam quantrill]

Thinking about it, the sensible thing is to adjust the fuel/air ratio at significant throttle openings. The idle mixture is easily set by the bypass on the AFM. What you can't change easily is the mixture while running, unless you have an adjustable fuel regulator.

You'd probably need a rolling road to set it up.

I'd put a dab of paint or tipp-ex on the knob and the ECU so you can line it up again in case you have the urge to fiddle with it....

[pwd95]

Very tempted to have a fiddle but as you say it's probably better to have it fiddled with on a RR properly. Have to save some pennies.

Edited by pwd95 on Monday 4th September 12:47