Have a EF8 CRX doing circut racing and running a fully rebuilt b16A engine (gen 2)

It is running a type R intake manifold, 62mm throttle body cold air intake, and K&n filter, engine has the head shaved and is running 11.45:1 compression, and a set of Skunk cam gears ,standard everything else, tanabe 4-2-1 extractors and 2 1/4 inch mandrel exhaust running 2 resonators. And running a SPOON ecu

Now after a weekend of testing and racing on the second day checked the plugs to find that they are running almost white (running NGK irridiums) and also using race gas.

Now this means to me that the car is running very lean?????? So to make a quick fix we taped the fuelpressure regulator with a a rod and a hammer to crush it up to give it more fuel pressure this worked as the car started to run lumpy at idle and then wouldnt idle. But after another few laps came in and pulled them again and it had only midly made any difference they were still very white grey colour??

Car is running very well but dont understand why it appears to be running so lean or is this due to the race gas (AV gas) ??? Does the timing we have set have anything to do with it??, car is running almost full ignition advance and is running 1 degree advance on the inlet cam and 3 degrees retard on the exhaust cam. we had been playing with different settings all day and this seemed to be providing us with the most useable power

Is this a fuel problem ie needs more fuel pressure or something else
Plugs as far as I know are supposed to be running a lite creamy brown????????????

ANY IDEAS PLEASE HELP!!!!!!!!!!!!!!!!!!!!!!!!

 

Bump

 

The board moves slow on weekends.... might also try posting in tech forum

 

From what I've been told, relying on your plug color is not the way to tune your air/fuel. I previously have been running iridium plug and after 12,000 miles they were white as a ghost. My car was A/F tune between 12:1 - 13:1 so I know it is not running lean. What plug temp were you using?

Also your cam gear settings seem a little off, when milling the head you are already retarding your cam timing. You may want to get on a dyno and try more advance on your intake cam and less on your exhaust along with A/F tuning.

 

Sorry, previous post was from me, under my friends screen name.

 

6's I thought I should go to the cooler plug the 7's

So from your experience the plugs running white/grey are OK???? The colour of the deposit in the exhaust is milky grey?

No the timing is working very well we have been recording with a camera inside the car and are consistantly better time wise around the track so time says it all???

Have tried from one end of the scale to the other and this is where the times are consistantly lower?

 

I doubt you need colder plugs, 6's should be fine. But you really should get the Air/Fuel done with a dyno.

 

Plug cuts DON'T WORK.

They used to, and were an effective tuning tool.

When class rules changed and I was allowed to run different ECU's, I tried to do the same with a fresh set of plugs. 2 laps, into the pits, WHOA!!!! Way lean!!!! (Or so I thought). Back to the stock ECU. Two more laps, same thing. Checked the method on my B18A Beater Civic, same result. Ditto my 323GTX.

I am completely at a loss as to why you can't do this anymore, but I'm sure it must relate to how clean cars are running these days. Hot, swirly, efficient combustion from well atomised fuel (thank fuel injection) and small chambers, I suppose.

Put your mind at ease. Get an AFR monitor, even if it is a "happy face/sad face" one. Better than nothing. Otherwise a WBO$$$$$$$$$$$$$

Jon

 

Whoa, a 323 GTX? Sweet...I wish I could find one of those. How's the understeer? It's AWD right?

 

The GTX is a blast in the winter, I bought it as the ultimate winter beater/sleeper, my sacrifice to the gods of road salt.

They aren't that hard to find.... a good one is, though!!

It's a blast in the snow, and with 16psi, reasonably quick. Understeer? You're not trying hard enough!!!

Seriously, though, you have a choice of full time, or LOCKED AWD, there's a lock switch on the dash. On snow and ice, it tends to snap oversteer when locked (that is, just after it's finished understeering), better to give up a bit of forward bite, and more reasonable cornering. Understeer got much better when I swapped to stiffer springs.

Jon

 

Yes but running and A/F gauge isnt going to solve my problem is it I want to know what colour you would expect the plugs to be and how from the situation I have solve the problem???

More fuel pressure????????

Bigger fuel pump?????????

 

Your CR might be high enough that your EGTs don't allow any HC's to deposit on the plugs. Plug color indicates combustion temp more than anything else, and with even a safe AFR you could be getting temps that one might see running lean on a pump gas setup courtesy of your high CR and really high ignition advance.

Get an AFR guage, it will give you a very general idea of where you are in the AFR spectrum. Right now you are stabbing at thin air with a blindfold on...

 

Yeah but it is runing on high octance gas (aviation fuel AVgas) 108octane

So what your saying is that it is probably just that I need to run colder plugs as the plugs are probably running way to hot!!!!!

Am going to fit an adjustible fuel pressure regulator and a fuel pressure gauge on the weekend?