Recently had my turbos replaced under the 82k warranty, so I went through some of the modding stages again... below I compiled some of the IAT logs between ICs. Very clear that an upgraded IC is important. I do think there’s a pretty big difference between aftermarket options and I have shown this before based on my experiences… specifically between Helix and AMS.
Why is an “aftermarket” IC important. Of course temp for spark timing… lower IAT, less chance for detonation, and more timing advance putting you closer to MBT. If running E85 and/or meth, timing is not so important since the octane will allow a proper timing curve, BUT:
E85: apart from the tuning aspect (DME IAT compensation), IATs effect oxygen density. Lower the temp, higher the density, more O2 = more power. Someone else can do the math on 20, 30deg which is significant.
Meth (post-IC): People see their IATs on Meth and think no need for an IC. What they are seeing is NOT the true IAT. Meth cools the air, but not to the degree that’s seen in the logs. IAT sensor output is a false reading due to “wet bulb effect”. How much is it false, I can’t say. I can say that the apprx IAT % increase you see off meth is also happening on meth. There’s NO heat soak suppression with Meth… you just can’t see it in the log. The IC is heak soaking at the same rate on/off meth. Meth temp decrease from evaporation is a %... so final IAT depends on the temp post IC… doesn't matter what the IAT sensor is reading.
Anyway, to the logs. Very simply I chose randomish logs with Helix and stock IC. The tuning in these comparisons is relatively close… lowish boost around 14, 15psi mid-range to 13ish at 6k rpms. Some of the runs are while moving, some after a stop light with static heat… some back to back… basically random. All OFF meth of course.
Depending on the new turbo rep points I get, I’ll post some more threads of random info I’ve learned. Maybe ATR tuning, specifics on stacking, other stuff. Tomorrow I may run out and do some virtual logs to compile pre/post DP install… that should be interesting. Have some good ones pre-DP. But we’ll see if the reps are worth the effort…
ps. don't make fun of some of the boost curves... I was dialing in the new turbos. Wasn't so easy after having very loose WGs.
Why is an “aftermarket” IC important. Of course temp for spark timing… lower IAT, less chance for detonation, and more timing advance putting you closer to MBT. If running E85 and/or meth, timing is not so important since the octane will allow a proper timing curve, BUT:
E85: apart from the tuning aspect (DME IAT compensation), IATs effect oxygen density. Lower the temp, higher the density, more O2 = more power. Someone else can do the math on 20, 30deg which is significant.
Meth (post-IC): People see their IATs on Meth and think no need for an IC. What they are seeing is NOT the true IAT. Meth cools the air, but not to the degree that’s seen in the logs. IAT sensor output is a false reading due to “wet bulb effect”. How much is it false, I can’t say. I can say that the apprx IAT % increase you see off meth is also happening on meth. There’s NO heat soak suppression with Meth… you just can’t see it in the log. The IC is heak soaking at the same rate on/off meth. Meth temp decrease from evaporation is a %... so final IAT depends on the temp post IC… doesn't matter what the IAT sensor is reading.
Anyway, to the logs. Very simply I chose randomish logs with Helix and stock IC. The tuning in these comparisons is relatively close… lowish boost around 14, 15psi mid-range to 13ish at 6k rpms. Some of the runs are while moving, some after a stop light with static heat… some back to back… basically random. All OFF meth of course.
Depending on the new turbo rep points I get, I’ll post some more threads of random info I’ve learned. Maybe ATR tuning, specifics on stacking, other stuff. Tomorrow I may run out and do some virtual logs to compile pre/post DP install… that should be interesting. Have some good ones pre-DP. But we’ll see if the reps are worth the effort…
ps. don't make fun of some of the boost curves... I was dialing in the new turbos. Wasn't so easy after having very loose WGs.