A/F meter + Exhaust temp. gauge

[Pisobiker]

Hi all.
All this talking of huge turbos, monster cars, big hp, etc. etc......

To all of you, guys, seriosly interested in making power upgrades and to whom interested in experimenting engine mods I would strongly recomend fitting an "exhaust gas temperature gauge" (right gauge under steering wheel on picture below) and an "Air-to-fuel meter" (left gauge under steering wheel).
If ex-temps (sensor immediatly after turbo) raise above 830-850°C (which means over 950°C on ex-header) you definitly need to enrich fuel mixtures or, if A/F is OK, you reached max load allowed for actual engine setup.
A/F meter, instead, must read 14.5-14.7 at idle and steady rpm and light load, (~14.7 is stechiometric value), over 16.0 (out of scale in the lean side) in "releasing" conditions, and 13.0-13.5 at full throttle and load.

I have them since last February, and I found them very usefull (allowed me to find and get rid of a bug in my 350hp chipset, just to make an example).

Total cost of both ~140 Euros.
I've used my old 3B black "instrument panel" to fit them under the steering wheel.

Ciao

Marco

[sla_s2]

great mod. have you seen this one?

[sla_s2]

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[sla_s2]

7. overview of gauges is much more better imho.

sla s2
lithuania

[S2central.net]

Marco - what manufacturer of guages and probes did you use ?

And were you able to retain the standard lambda probe to keep the ECU happy ?


Paul

[Pisobiker]

Hi Sla,
yeah, mod you're suggesting puts gauges in a much more visible position. I would prefer, anyway, to have the adjustable venting system (direction+flow) fitted.

Paul.
I have to check at home if I can find gauge's manufacturer. Anyway I've bought them from a dealer in North of Italy also specialyzed in Subarus tuning. He has ensured the A/F meter can perfectly work in parallel with the ECU using the standard lambda sensor, without affecting ECU's reading at all.

Marco

[Mark Halligan]

Marco,

Agreed, these gauges give a lot of information, especially important with power upgrades.
I've had a EGT gauge on order for about three weeks (Greddy) which should hopefully be with me soon. Its the same make as my boost gauge and it has a resettable memory function which records the highest value measured and can be wired into a buzzer to warn if the engine is exceeding any pre-set values, warning the driver to back off.
A useful feature, as I have recently discovered that things can get a little rapid and don't leave time to watch much other than the rpm gauge
I will also fit a A/F meter too, but for the time being I'll make do with EGT as this kind of doubles up and gives an indication of lean mixture indicated by high EGT's.
The trouble is finding a place for them all as I like adjustable venting too.
I currently have the boost gauge in a single pillar mount (pic attached) and I will use a double mount to add the EGT.

Cheers, Mark.

[Pisobiker]

Ohh....I would have liked to have the "high value memory" feature on mine too ....
....but guess it would have costed a lot more .... so I'll be content with my ones.

Greddy's are very nice. Have also a great reputation.

Agree with you the most important of the two is the EGT. It will alert for both lean mixtures or engine "overload". Also having the A/F meter will reduce to 1 possible cause of problem.

Marco

[audiman]

Mark, where did you get that pillar pod?? I have been looking for one of them. Part no. etc would be useful m8. Cheers.

[Mark Halligan]

Tom,

Its made by Revotec I've seen it for sale in either single or double gauge (carbon look or leather grain), in quite a few 'go faster shops' but I got mine from Demon Tweeks.
Its in both of their catalogues (motorsport - page 163 and performance - page 189) they are made to fit 52mm gauges but can be adapted to take 60mm (which mine is). It also needed a bit of cutting and profiling to fit the S2 A - pillar, but its not a big job

Cheers, Mark.

[Mihnea]

Guys, be careful with A/F meters that plug onto the original O2 sensor, unfortunately the sensor isn't accurate at all except around 14.7:1, which means that when it indicates "rich", you only know it's rich, if you plug a wide-band O2 next to it, you'll see that when it says 13:1 it's actually 12 or sometimes 13.7 unfortunately.... so don't take that kind of A/F meter's readings for granted, sometimes they are useful when tuning but the O2 sensor's output curve also depends on surrounding temperatures, which highly complicates the issue....


HTH,


Mihnea, back from a tuning session in France :wacked: