c7jim

Have any new owners actually experienced the heat soak, power loss problem for themselves?

zhopper05

1,400 miles, four dyno pulls - not a single time.

EVL-C8

Nope!

TEXHAWK0

From what I read, there is no heat soak power loss. Power is reduced by factory emissions tuning limitations.

sam90lx

There is something going on, Nspec and Nine ***** runs showed the Z06 getting pulled more and more as the runs went on. Some will say it is not heat soak but I don't buy it. My 03 SVT Cobra would do the same thing the more times you ran it back to back....it would slow down due the Eaton getting spun so hard and getting so hot.

CaryBob

I cannot recall anyone with proof that heat soak occurs. I am not denying that something may be going on, just that heat soak has not been proven to be the cause. Or even that there is correlation. It would be very helpful if we could gather some data that separates cause and effect.

occar

As easy as it is to log timing advance and temps one would think someone would have provided a log by now....

Hirohawa

Not sure if this qualifies as proof but this is from Vette Magazines recent test of the C7 Z06:

"Downside? The blower gets insanely hot and takes forever to cool down. Even after putting two bags of ice on top of it for 20 minutes, the supercharger was too hot touch. Heat soak is a serious hindrance to track performance. Combined with 85-degree temps and 70 percent humidity, we could not match GM’s dragstrip numbers, which were recorded on a prepped track on a 65-degree day."

http://www.superchevy.com/features/2...ng-boundaries/

occar

Yeah no. Most engine components of a warmed up engine are "too hot to touch". IAT and timing advance logs is data. That's just "writing".

Snorman

Data will tell whether or not there is really "heat soak". But to rely on magazine writers is far more scientific.
S.

sam90lx

Yeah no? How about in English, tell us what you really mean.

Hirohawa

What about the "data" where they weren't able to match GMs 1/4 mile time? And how they attribute it to "heat soak". Is that also just "writing".

Are you guys done being "clever"?

OnPoint

So how is it that Lawdogg got his best 0-60 pdr run on run #25 of 30 back to back runs?

Viper_Vette

Ouch that doesn't sound good.

Snorman

Let's just ignore this part:
Let's also ignore the fact that not only did a number of initial magazine tests not match GM's claims for the C7, but owners ran up to .7 quicker than GM's published times.

One does not need to be very clever to recognize these facts.

BTW...what are the IAT2's?
S.

Snorman

Let's forget this part too (or better yet, not even mention it ):
S.

Bill Dearborn

Short dyno runs, zippitty do dah runs on a highway and drag strip runs really don't prove anything. The car has to be run continuously hard for 15 to 20 minutes. Dyno pulls don't last much longer than a 12 second drag race so really don't let the engine get hot.

Bill

AtlM5

From the IATs floating around on this forum and what the tuners are saying, I'd say there is not a heatsoak issue. It seems there is overzealous pulling of timing from a lot of other factors adding up. It is basically an overly consertive ecu for emissions. A simple 160F thermostat will likely solve this. All this will do is turn the fans on sooner before the engine gets too hot. This higher temp thermostat, along with the relatively low oil viscosity were done to improve emissions just as has been done to other cars. All of these emissions regulations are starting to get crazy.

sam90lx

Good point, defective PDR?

heavychevy

0-60 is almost entirely reliant on the launch. I doubt it will be affected much by timing pull. Especially if he was getting better and better at launching each time. It makes sense that the best pass would come near the end of his runs.