RB25DET AFR

[lilskyline240]

the stock ecu does run nitoriously rich. but yours seems wayyy too rich. even for the stock computer. Doubt check everything else before you start leaning it out with the SAFC. All your doin is covering up the problem you have which eventually could be bad

[matafied]

NGK's for Rb's SUCK!!!! AC delco also 6800 is stock redline

[DrifterProdigy85]

Seriously, Whats the difference in NGK and AC Delco? Why would NGK run awesome on my SR and not RB? Doesnt make any sense. As long as the Coilpacks are getting power to the spark plug, they should work fine. Yea i follow you about covering up a problem. I still have yet to check the timing. Have to wait for my SR to be done and out the garage before i do anything else with the RB.

[DrifterProdigy85]

Oh yea, on the plus side, ive only seen 1 knock so far while driving. Stays at 0 @ WOT. I wouldnt be surprised if the timing is retarded some.

[lilskyline240]

you make sure your maf and o2 sensor are good? also didnt you say when u ran the codes you got a coolant temp sensor code? that would be your problem right there

[rb25drag]

NGK plugs run like crap in my RB, I have tried 3 different sets at 13.99 per plug=251.82$ worth. I get a misfire and a detonation around 4500 on anything over 6lbs of boost. Switched to the A/c Delco 3.99 a plug only used one st so far 23.94$ and It runs perfect all the way threw 6800rpm on 10lbs of boost extremely nice. same gap and safe fuel setup. So to me thats proof for the a/c delco. Might not be the same on every RB but mine hates NGK!!! Not a fan. Your timing is automatically going retard on the big end that why its running rich!!! You can bump you timing a bit but it more than likely will not stay there. So the AFC is going to be your friend in this battle. Good luck

[ST240]

After fixing my boost leaks and exhaust leaks, ive finally gotten a solid AFR reading. Currently its 11.5 AFR @ 10psi and 12.5 AFR @ 13-14psi. Is 12.5 AFR still safe with the stock ECU?

Modified by DrifterProdigy85 at 8:52 PM 10/1/2007

Just curious as to what AFR gauge youre using (or were using) initially?

[lilskyline240]

do you have your wideband sensor at least 18 inches from the engine?

rb25drag ~ are you using iridiums? or regular plugs?

[rb25drag]

IM using regular number 4 cold plugs.

[blurrbosi]

iridiums work fine for me. Stock ecu they did sputter from time to time when @ high boost. ie: above 11psi...

[lilskyline240]

iridiums work fine for me. Stock ecu they did sputter from time to time when @ high boost. ie: above 11psi...

NGK iridiums?

[DrifterProdigy85]

After a few days of driving and tuning some. Ive got the AFR to run pretty solid at 11.6 around 4krpm and richens slightly to 11.3 by redline. I no longer miss running 10psi. I havnt ran 13psi yet. How much power is the stock MAF good for? Im reading 90% airflow @ 10psi. Wouldnt doubt that 13-14psi will max it out. Im using an AEM Uego. Placed in the downpipe which is far enough away. The car runs really good now being pretty in tune. 3rd likes to spin some @ 10psi on 215/45-17 Dunlops. Im thinking the stock ecu just runs rich at high rpm.

[rb25drag]

Sounds like your onto something. 11.3 isnt that rich, its about right. Plus I would run a little rich any day over a little lean.

Did you check your timing? Wat was it set at?

Wat plugs did you go with?

[DrifterProdigy85]

Havnt checked timing yet. Still using NGK Iridium 6 Plugs gapped at .030". I ran 12.5psi tonight and didnt miss a beat. Tuning is just what the car needed. I got one spike in knock when running 10psi earlier and it was right when the AFR dipped down to 11.0. I leaned that out to 11.4 and no knock showed up. It seems the plugs miss easily when rich for some reason. What part # is the AC Delco Plugs?

[DrifterProdigy85]

Also where can i get a new stock BOV gasket? I bought a SARD BOV but the kit didnt come with a gasket.

[rb25drag]

ACDELCO #4

I guarantee ya they work alot better.

[lilskyline240]

what you have your plugs gaped at rb25drag?

[rb25drag]

.08mm approx (.028)

[matafied]

I was tuning up a 05 Monte Carlo v6 and on a whim compared them, they looked close and threw them in my car and vahla so if you need a reference you could go by that lol still in my car today

[DrifterProdigy85]

I checked the timing today. Not exactly sure where its at because i was looking for a pointer sticking out to show me but all i saw was a raised area on the front cover. Going by the raised area it was showing 16-17*. If someone could get me a picture of the timing mark that would be great. I slotted my spark plug cover also to disipate some heat. I figured it could only help.