IAT's, Timing and other things I've forgotten. Calling the old timers and tuners.

Hey guys it's been a while,

Well I didn't get a SC, but got a new supercharged car. Well I had some questions form the old timers.

What is typical timing for an SC engine under at full load boost levels?

What is the typical IAT for the same. I don't remember what the temps were, but it seems like someone had numbers at some time.

Thanks,

Jeff

J57ltr said:

Hey guys it's been a while,

Well I didn't get a SC, but got a new supercharged car. Well I had some questions form the old timers.

What is typical timing for an SC engine under at full load boost levels?

What is the typical IAT for the same. I don't remember what the temps were, but it seems like someone had numbers at some time.

Thanks,

Jeff

Click to expand...

The timing I cant give much info on, but with the IAT's, it all depends on if it has an intercooler, and if it does, how efficient is it.
With my 13 F150 EcoBoost on the stock intercooler, the IAT at cruise would be 5-10 degrees above ambient, and up to 50-60 degrees above ambient at WOT. It heat soaks very quickly.
When I put the AMR intercooler on it with a 5" core, the IAT's would be at ambient at cruise, and never seen more than 8 degrees above ambient at WOT ,and that sucker is impossible to heat soak. No with meth, I could get it 30-40 degrees below ambient at WOT. lol

So it all depends on boost and intercooler efficiency.

I'm talking more specifically SC related only I ended up buying a 05'GTP and these guys are talking about 15-18* of lead at WOT seemed to me that it was about 26-28* on the SC. they have no idea what their inlet temps are. I was remember seeing threads of before, after and ambient temps. Threads about blower outlet temps and that's what I looking for.

Jeff

Jeff, that's about right. People used to run a commanded 26-28 but that was with 100% knock retard kicking in and still getting borderline detonation. Once you start porting heads then spark requirements change, but for a stock SC, 18 deg is a pretty solid #. IAT's in the 120-180 range are normal for a stock SC depending on conditions. I imagine a GTP would see temps over 200 but I don't have any experience.

Dave! How the hell are you? Man that's what I was thinking. I'm having what looks like a bad knock sensor and its pulling me down to 0* and as crazy as -15* this thing is nuts it is capable of completely out of boost by forcing the bypass open and limiting throttle travel DBW. There aren't a lot of guys that know the pcm like the guys knew the EECIV. It will even shut the engine down fixing the timing at -15* and dead rich. I bought an app and a module that plugs into OBD2 connector and reads real time on a phone or tablet. These guys are saying that inlet temp doesn't matter and you have to tune around high temps. As I recall in that test it was a proportional raise in temp with inlet temp right?


Thanks,

Jeff

Even with high heat the engine needs at least 10 deg timing to run worth a damn. Our EEC's are only capable of pulling 8-10 deg from commanded via the knock sensor and about 4-6 on IAT, so with heat and full knock retard you'll still get 8-12deg minimum with everything pegged.

If the motor has a lot of carbon in it or uses oil it may be knocking when it shouldn't, or it may have a mechanical problem like a rod bearing forcing knock retard. Otherwise I guess bad knock sensor? Can you shut it off? I generally shut them off in the SC's because they more or less only work correctly when the engine is stock which at the point they never are. lol

You should get an SC again, our tuning tools kill whatever you have available. lol We can do live tuning and full speed wide range datalogging (all pids). Not may secrets anymore.

I've been impressed with how GTP's can still perform the way that they do without an intercooler. One thing that I know on my n/a 3.8 'Stang on a Bama tune, it hits 39-40 degrees of advance at cruise speeds, and about 32-34 at WOT, and it's right at the absolute edge of MBT spark.