Overfueling Issues :(

[got_boost!]

Well I just finished a total rebuild on my RB20 project. Everything nice and new and shiny from the block up and my hands have been on or in all of it which is kind of nice.

Anyways, engine runs like she just came off the factory floor. HOWEVER..... I'm running stupid rich. I have put in 444cc injectors running off a 255 lph Walboro with other associated mods (not the fuel rail though) but would those alone cause a major overfuleing problem?? I just went out this morning and bought brand new NGK Iridium BCPR6EIX-11. My old plugs were BLACK!!!! Like totally fouled out with soot. I put the new plugs in and it took all of 30 seconds for them to look the same. Is the gap possibly too big on the plugs and I'm blowing out the spark? In the sticky in this section it says to use BCPR6EIX but it doesn't specify a gap setting. The guy at Autovalue seemed to think 11 was way too wide and at most I should be running a 7?

I'm scheduled for a full tune on on the dyno on Tuesday, but I just didn't think the injectors would run that much more that I wouldn't be able to run the car almost at all. It sounds like a diesel after about a full two minutes. Any suggestions??

P.S. Coils all tested fine and igniter box should be fine as well. All plugs had even burn on them until the new injectors went in....

[Supraclean]

Did you upgrade to an aftermarket FPR? Not to the stock one would not be albe to handle the flow increase I would think.

[kyles_r32]

gap them a .8mm and its definitly going to run rich with out a proper tune...what kind of ecu are you running?? The stock injectors are like 270cc..

[Skym]

R32 RB20DET injectors = 259cc. The 135lph fuelpump (for 370cc injectors) makes them look like 270cc injectors.

You'll need to change the injection settings on stock ECU and adjust fuelmap with bigger injectors. Also good time to add Z32 AFM + Z32 AFM plug at same time, as retune of ECU is needed.

Think of it this way, if 1.7% (stock RB20DET) duty cycle on fuel map at idle -

1.7% of 259cc = 4.403cc

1.7% of 444cc = 7.548cc

Add fuelpump that's 60lph bigger (195lph for stock GTR vs 255lph fuelpump) = overfueling.

Try buying copper NGK sparkplugs, much cheaper. But have to change them earlier (every 10,000km or so).