Running Rich

**shebangs** · 15-02-2007 01:17 PM

Is it bad to run rich?

Went for a squirt just before, coming back my mate said I'm blowing black smoke out the back in VTEC. Bit of a search on ht.com says I'm running Rich on fuel. Car was fairly warn (was only a 5 min quiet drive, usually I like to ger her at least 10)

Mods are: i/h/e, dyno tuned s200, flywheel and clutch.

If it is running rich, is it bad? Could it be a sensor out of whack thats causing the the fuel maps to be wrong? It was recently tuned (6 months ago) so I can't imagine it was tuned purposely to run rich or is that a normal thing todo? (BLKCRX tuned it)

Matt

**JasonGilholme** · 15-02-2007 01:32 PM

Might need to change your PCV valve first before worrying about the tune. It's a cheaper solution and could possibly fix your problem before you go spending big bucks on re-tuning etc.

**EuroDude** · 15-02-2007 01:36 PM

A bit of black smoke during VTEC is normal, the engine does this to protect itself.

**JasonGilholme** · 15-02-2007 01:39 PM

I don't get black smoke? brand new ones don't blow smoke...

**aaronng** · 15-02-2007 01:44 PM

Your tune is set rich under vtec and full throttle so that your engine is protected from running too lean. You can gain more power at high RPM by going leaner (and having less black smoke), but you risk too high a combustion temperature, which can damage pistons, valves and spark plugs.

**aaronng** · 15-02-2007 03:48 PM

Originally Posted by poid

even still, when warmed up properly there shouldnt be black smoke if its tuned right (even a little rich).

I wanna know if it does the same if he's driven it for a longer period. The oil often takes up to 10 mins to get up to temp and coolant gauges can be misleading.

I've seen a totally stock b16a2, fully warmed up, drive without smoke up to 5000rpm. When at full throttle 6000rpm, it blows a puff of black smoke at the beginning but then it clears up after that when it has gone to about 7500rpm. I reckon its set rich to protect the engine.

**EuroDude** · 15-02-2007 03:53 PM

And its not just a Honda thing, Ive seen new Commodores blow dark smoke when revved hard.

**shebangs** · 15-02-2007 03:56 PM

I don't have guages yet (Defi guages are coming) so my basis for assuming she was warm was Water Temp on the dash.

I didn't shift at my redline (8600) either, only took her too 7500.

I'm fairly confident I am running rich, as sometimes when I downshift my exhaust backfires and/or crackles. My question is though, wheres the limit to running rich, safety, but losing power. Is it damaging any other parts of my engine? Can I still assume shes tip top?

Toda Internals and Cams are next, and considering my setup pulls 115 at the wheels I'd like to think my engine was tip top before I pulled her apart.