Vortech V3 tuning issue, stock engine/pulley

[5lho]

I'm chasing two thing: A supposed vac leak and KR issues.

I can't find ANYTHING re. the vac leak. but, the fuel trims are wacky, out by like 13%. Can't figure it out. I've propaned every connection, redone the BOV piping, taken off the powered side of the PCV and plugged the mani port. No cure. Next is t bolts between the MAF and TB and checking the TB. I can't believe its injector seals, as they looked great and seated properly going in.

On top of that I have heavy KR action, the car will barely take 10 degrees before it starts pulling timing. I've been told on stock Vortech pulley, stock airbox, etc. I should be able to see 17 degrees. That one's the real mystery. No misfire events at all, even on these used stock plugs, gapped .035. The car`s a real dog at 10 degrees, I assure you.

I suggested maybe we go at this from the other side. Put in the timing to what is expected, I'll give it a quick jab and if it rattles, we have a real problem and not ghost knock or something.


Any ideas on either of these appreciated. It's making me and my tuner crazy.

 

[blownGTvert]

start with 1 heat range colder plugs gapped at.032". I would agree that 17 deg @ WOT is reasonable for 93 pump. So 10 deg appears low. However, the ECM pulls timing for high IAT and engine temps. So you need to log both along with spark.

As far as the tune, I would NOT add timing until to get some solid logs. Adding timing in the BKT and MBT tables isn't your overall timing. There are adders like VCT tables, as well as multipliers, that impact your final timing values.

 

[5lho]

ECT is ~190-198 degrees and IAT was under 26-32 C the whole time, which is roughly ambient around here lately so, I can't see it pulling timing for those reasons. It isn't boiling hot here, generally this summer has been low to mid 80s F. It doesn't seem to be the kind of conditions that would merit colder plugs, given the low boost. I'm running 94 octane super premium gas as well.

Maybe I am wrong?

 

[konablue11gt]

Try a tune from a good tuner ...not to be blunt but your combo is an easy one now there is a ton of data available to the guys that have been tuning them. And yes you should be running one step colder plugs gapped around .032

 

[5lho]

Not blaming the tuner. He is identifying issues in the engine operation that are real. It is pulling timing for some reason. It is wacky on the fuel trims for some reason. These are peculiarities I am trying to figure out. the tune itself, as you say, is dead easy if I can figure out these quirks.

I am going to recheck the TB connections today, T bolt everything and put colder plugs in. Hopefully i get a positive impact from that.

 

[Blackbeast12]

Bad fuel....? Dump a bottle of lucas octane booster and see if anything changes!!

 

[5lho]

94 octane super premium form the same stations I always buy at and I've gone through a couple tanks tuning it so, unlikely. Tune is designed around 91 octane.

No misfire events or anything. Car definitely perked up a bit on the latest version of the tune, after I t-bolted the cold side and put fresh NGK colder plugs in. I'll log it today.

 

[konablue11gt]

Look for exhaust rattles or knocks against other things the engine may be interpreting as a knock condition. The only reason it could be pulling timing is knocks and can in fact be something as simple as a pipe too close to another thing or exhaust leaking being picked up by knock sensors

 

[5lho]

DL today showed the same events. NGK iridium IXs in, one step colder, gapped at .032. What makes me think it might be real is the fact there is a quick spike in KR and the a gradual ramping back of KR as revs rise. A ghost knock situation might, I think, show a quick spike and a quicker correction. Guess it depends on how the ecm is programmed to respond to a KR event.

I've gone through all the pipes repeatedly, making every effort to isolate them from one another, inside the couplers and away from an underhood stuff. Where contact even might happen, I insulated the pipe with sections of rad hose.

I'm about out of ideas, hopefully my tuner isn't.