green tune resistor

[slideways]

Hi all,
at the moment i am running a white tune resistor with the lambdas since ive decatted the exhaust,
can anyone explain what gains if any i would see if i lose the lambdas and change to a green resistor
Ta
Rich

[blitzracing]

None what so ever. No power gains and wrong fuel map (Likely to be stock Range Rover). The Range Rover map is said to run lean anyway which is bad news.

[GAVC]

I understand the green tune resistor disables the signals from the lambda's, that's all. The lambda's can be left in and will still provide signals to the ECU, it just doesn't read them as the green tune resistor disables the signals.

If you want gains, then you need to look elsewhere

[spend]

You might be able to find a suitable map for the selection in one of the pre-cat chips. I don't think any of the pre-cat owners have changed ecu, but TVRPower/CRE have some chips IIRC.

ETA: I think JE has some too, someone I know has a 5.0 decat chip from John sat on the shelf IIRC

Edited by spend on Saturday 1st November 10:12

[nicktowe]

GAVC said:

I understand the green tune resistor disables the signals from the lambda's, that's all. The lambda's can be left in and will still provide signals to the ECU, it just doesn't read them as the green tune resistor disables the signals.

If you want gains, then you need to look elsewhere

Surely it does more than disable the signals, it i supposed to select the map. Blitzracing really knows what he is talking about here, he has studied the maps in detail.

[GreenV8S]

nicktowe said:

Surely it does more than disable the signals, it i supposed to select the map.

It selects the configuration to use i.e. which map and which options such as lambda feedback. Whether a different configuration would be better or worse for that engine is impossible to predict, but there's no particular reason to expect it to be noticeably better and it *could* be a lot worse.

[slideways]

Thanks guys
i wont bother going down that road then
ta
Rich

[blitzracing]

As Green says it a bit of a lottery as to what your non cat map might be, and unless you are going to put it on a rolling road, and test the mixture under various loads you won’t know. The big advantage of the catalyst map, is it keeps the fuelling really accurate under light to medium loads, which is good for fuel economy and emissions. I gained 6 mpg on my non cat car running the cat map and it still goes open loop when you need full power, so you don’t loose any power. The only problem is the "catalyst clean" cycle the fuelling follows that in some cases causes some snatching at low RPM. If your car does not do it, nothing to be gained what so ever.

Mark

[slideways]

tbh my car drive really well at all rmps so i'll leave it as it is for now

Rich

[grahamw48]

My Wedge 400SE hotwire has a Chim 400HC motor fitted, with matching ECU, tune resistor changed to suit non-cat,new 'Real Steel' 218/220 cam fitted.

The engine runs absolutely faultlessly and smoothly (touchwood), no shunting, and with plenty of power and torque from 1000rpm...certainly on a par with my previous 390SE, which was no slouch. Whizzes up to 6,000rpm.

Economy is better than the 390, probably +20mpg on a run.

[dhf]

With full decatt my tune resister was inadvertantly set on the white setting.i can't say anything for power/mpg gains but it produced a very loud rifle shot bang at about 2500rpm coming down the revs in 2nd and 3rd,which sadly speeded on the demise of one or two pensioners..........

[Rallsy]

Hi all.

On the subject of green tune resistors, does anyone have one for sale or know where I can get one please?

Cheers