Rich or Lean ?

[Justin182]

Just looking for a little info to ease my mind lol

I have an ITG panel filter, Janspeed backbox and inlets matched so i would have thought i would be running lean.... correct?

Anyway, i have been told that the std ECU can over correct lean running engines and make them slightly rich... this correct ?

I am planning on having my ECU custom mapped but cant till mid june and the problem is that i am driving from edinburgh to into france with mates, and prob wont want to hang around.

However, my exhaust pops a bit and gets sooty exhasut tips which it didnt do before so is this a sign of running rich and what are the bad points of running rich of lean?

Thanks

 

[rory182]

ur mad to drive to France in it if not running right IMO, get it re-mapped before the trip no question.

running lean can burn the valves seats out

 

[Justin182]

But if it was running rich... would that be ok over long distance apart from using more fuel. I not driving much in france just to this side of it.

And Dastek near me cant do it for a month and chipwizards can till mid june so that leaves a SMT6 which is serioius bucks.

 

[Justin182]

Would a garage be able to tell me my AFR ?

 

[White16valver]

running rich is fine as far as I know, but your Cat might not like it too much lol

 

[Ali]

^ Richer means Bugger...Could still be running lean bottom End...

It's unlikely that the engine will be running overly rich.

 

[Justin182]

I dont think it is too bad. It only gets sooty after long or fast journeys.

Would an average garage be able to tell you your Air/fuel ratio or do ypu need a dyno etc...

 

[Ali]

Spk to Ben Mate....

 

[ja.jack]

Bung on a group n ecu.

 

[16v_jon]

The standard ecu wont allow the engine to runoverly rich or lean, it will compensate and try to run stoichometric (14 air/ 1 fuel) as much as it can.
it has loads of default permeters built in and can run with no sensors attached ( not very well )

 

[BenR]

Its a tricky one.

In most cases once you add a modified inlet, it will be running lean. The std ECU doesnt correct in the traditional manner of closed loop to account for lean conditions. This is because the stock lambda sensor doesnt have the range necessary to measure the correct full load AFR. It will most likely be running fine on mild throttle and cruising below 4400rpm, but on full pelt, i'd put my finger on it and say it was/is running lean.

 

[Justin182]

So basically, i should be fine driving long distance and fast-ish till mid june ?

 

[BenR]

i wouldnt do 'fast', constant high rpm/high load will see you steadily increasing chamber/head temps until knock sets in, followed possibly by det which can knock out a piston. Extreem case, but not unlikely if your running excessively lean.

 

[Justin182]

Just saw you post Ben.....

So would running the car for long periods at 4400rpm which I think is around 90-100 or regually horse it upto 6500 when accelerating be damaging to the engine?

Any idea why I get soot on the exhaust tips on long or fast journeys? Thought this meant it was running rich?

lol.... i so confused

 

[Justin182]

Ok... thanks Ben. Answered my question.

 

[BenR]

hoofing it and any full throttle action anywhere will see you entering the danger zone.

Carbon buildup is a natural part of burning hydrocarbons, rich/lean it will happen.

 

[osbid172]

I read with interest,
I've got the same mods but not yet had a remap.
And I do like to give it some stick.
I'm like Justin182-a little worried

So,will an off the self superchip or group n make the correct adjustments to fuel/air ratio.

If I fit one will it be sorted? (maybe not the most highly tuned solution but at least its sorted)

 

[BenR]

Manifolds cant be accounted for perfectly, like any engine really, with a 'chip. This is because they are done by different people, who's skills vary drastically.

An off the shelf chip, imo, might make it better, but wont bring it inline with what it should be.