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Spark Plug Symptoms: Fuel Mixture, Timing Queries..

Paulusc44

By Paulusc44,
in Engines & Forced Induction

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Paulusc44 Enthusiast

Paulusc44

Posted
Posted

Hey all,

Have just removed the plugs out of my recently converted R32 RB25DE+T.. Engine has only been running all up since installed for maybe 1-2 Hours max.. (Engine has done 190,000 Kms)

Plugs were brand new and are absolutely coated in carbon, also I noticed they were BK5RE's? Im going run BCPR6E's gapped to 0.8mm which I will install tomorrow.. Im sure the mixture is to lean if anything (ecu is currently being re-tuned) Could the timing be too far retarded? What else would explain the carbon deposits? Coils are in excellent condition as is the rest of the ignition system.. Would the plugs themselves account for this? Im also going to install a couple of fresh earth's.. Were would be the most effective place for these to be installed?

Finally the car was sitting for 24 months plus with bugger all fuel in it.. Ive since thrown 20 litres of 98 Octane Gull Force 10 (Available in NZ, contains 10 percent eth.)

Im going to throw in another 10 litres of 95 octane regular unleaded and wanted to add an octane boost to ensure its healthy as.. Are these worth while or are they detrimental to running etc?

All help appreciated :)

Cheers again

scotty nm35 Grand Master

scotty nm35

Posted
Posted

Octane booster isn't the answer... Ever.

Old fuel can cause all sorts of issues, flush the old crap out on the dyno and replace it with fresh. If you still have an issue tuning I would get your injectors checked.

KiwiRS4T Grand Master

KiwiRS4T

Posted
Posted

Haha no worries..

Any info regarding engine earths particularly for the RB engine?

I've seen earth kits put on them but don't know if they make any difference. Ethanol will help to clean out your tank but you will need to change your in-line filter now and again soon. What kind of tunable ecu do you have?

Paulusc44 Enthusiast

Paulusc44

Posted
  • Author
Posted (edited)

why even ask...

You know the longer you make the earths the more resistance you add and in turn could be adding more noise rather than a nice clean short low ohmage earth.

Lol you add about 0.2 Volts resistance max for each metre of wire used at the gauge I was referring too, was just hoping to grab some info on what parts of the engine respond best to an improved earth, allgood, have found some info this arvo :)

Edited by Paulusc44
STATUS Grand Master

STATUS

Posted
Posted

it needs a tune, same as the answers you got in the other thread when you asked about detonation.

http://www.sau.com.au/forums/topic/459711-rb2025det-turbo-conversion-detonation-issues/#entry7603659

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