There's a massive difference between the timing map you'd run with meth injection versus no meth injection. You are getting away with the stock timing BECAUSE of your meth injection.

You cannot run 27 degrees of timing in a boosted F20C without meth injection on pump gas.

 

I run 22deg timing 7psi CTSC but have custom front intercooler. 346whp Dynojet. I think the problem could be several factors, the baseline timing setup could be off mark affecting the rest of the map, superchargers don't generate much heat but overheated air causes problems anyway. Heck even the original comptech's or SOS kits run on stock timing at 5-6psi. To be on safe side pull timing go to a dyno with the fuel/timing templates you already have and see if they provide power if not then start pulling timing until you see drop of power then increase a bit. You already are doing logs so you know how your setup behaves so use your common sense and you'll be alright.

 

If you re read my post I said in my experience I have had no detonation problems running 9psi on the stock timing map with no meth injection. If your AIT are at proper levels with a working A/C and a conservative afr its not a problem. I would only run that set up on the street however and not the track, no point in being pushing fate if you don't have to.

 

Right. Statistical sampling of 1...you are an outlier. If we had 10,000 cars with your exact setup (minus the meth) and timing, you would see the positive correlation between running that much timing at 9 psi and mechanical failures. But, you'll be prompt to point out, these were merely your experiences.

Conservatively speaking, you were running 30% more advanced timing than what an experienced tuner might feel comfortable tuning your car to.

For whatever reason, plugs, temp, high altitude, humidity, lack of heat soak/charge temp, extra rich tuning , or luck, you didn't have a problem. People should not read this thread and think that interpolating the stock ignition map out is okay at boost levels above what's been proven over the last 10 years.

 

I do agree with this.

And I don't expect people to run out and try this, I'm not hear to debate anything either. I have put allot of miles of trial and error on my car with the comptech to find what the limitations are. I cant run a full stand alone do to smog testing and I don't like the tune quality of piggy backs so its forced me to get creative.

My goal in mentioning my experience here was to show a little contrast to the normal wave of thought on tuning this set up at the particular boost level and show what is possible. I also wanted to express my opinion that the AIT was what destroyed the OP motor and not becuase there was a little too much timing left on the table, that doesn't fly with me. Remember it is roughly only 2-3psi above the stock comptech system and there is no timing reduction incorporated with great success.

Now I've run as high as 10.5psi with no meth or timing retard and did have some detonation pre vtec in some cases, though likely not enough to kill a motor on the street unless it was abused. But as mention the OP was tracking so it all needs to be weighed out. I do know centrifugal blowers are a hell of a lot more forgiving then any other FI system on our car.

 

Alright. OP, you detonated because of high intake air temps. Address those.

 

^stats student?

that class was a blast.

 

High intake temps ?????? I dont think so ! 95 degrees f is NOT very hot at all . Ive seen 130+ on my turbo car . Do youre self a favor and talk to a pro tuner and end this bickering nonsence !

 

^^^ your right 95 AIT would not be a problem. Now if you re read the op post I quoted bellow you will see where I am coming from.

"I'm looking to avoid having the same catastrophe again. I suspect the original cause of failure was due to a misfill of the aftercooler on my part after a change to the 3.6in psi pulley. (I'm assuming) I recall not having filled again after cycling the pump. When I inspected the engine, the aftercooler water level was at the bottom of the heat exchanger in the resevoir."