A little FYI lesson for all…
In this video I take the ZR1 to the Dyno to see how much power this monster is making. The numbers caught me off guard till we figured out the cause.

 

The cause was .... ?

 

First dyno I’ve seen of ZR1 on 91 octane. Definitely makes a difference vs 93 octane. For us poor souls in the western states with 91 only there is a workaround. I fill my ZR1 with 91 octane non ethanol (sorry CA you are screwed) then drive about 30 miles and add 2-2.5 gallons of E85. Voila, 93.5+ octane at 15% ethanol, meeting GM’s max ethanol specifications. Goes like hell. I’m averaging 14.5 MPG with mostly around town driving. I get 18 MPG highway at 75 mph. I could care less about mileage.

 

We are lucky to have 94 octane at the pump here. I was thinking about adding a can of VP Octane Boost ( unleaded ) to each tank as well.

 

I explained the thoroughly multiple times in the video

 

We have 91 octane here except one gas station carries 100 unleaded at the pump. I have a bone stock 26 ZR1. I filled it up with 8 gallons of 91 and 8 gallons of 100 unleaded and by the time i got home my car threw a CEL and died in my driveway. It then putted around making the absolute worst sounds and kept dying every few miles until i burned off about half the tank and then filled it up with 91, and everything went back to normal.

I used the same mixture in my bone stock 24 z06 countless times without any problems whatsoever. Anyone know why?

 

Unless you got contaminated fuel for some reason- there is no way what you're describing is fuel related

 

i dunno, the only time it happened is right after i pumped the 100 and drove home (about 40 miles) and stopped as soon as i got rid of most of it, and has never happened since. I have about 2500 miles on it now.

Also, I pumped 4 5 gallon jugs of the stuff as well and put some in my AMG GLC63 to test it and there were no problems. I'm too scared to put it in my ZR1 again for now.

 

High octane alone won't cause stalling and noise

low octane will cause noise, but not stalling unless a piston breaks

something else was going on. Any CEL?

 

Yes, the CEL showed cylinder misfire. Which never happened again after I filled it back up with the 91

 

Expensive car to be playing those mad scientist games with buddy ... You trying to put GM warranty to the test ?

I think one can of VP octane boost per tank will raise you up to 94-95 octane and the car will be happy.

 

that's very unusual, I’ve done that mix with my Z06 no issues many many many times on street and on drag strip and on road course

 

I'm sorry that happened, but octane alone isn't responsible. Sounds like the fuel you got was bad or contaminated. Which isn't unheard of, esp in a low turn-over fuel like $9/gal 100 octane

Another possible theory is that the 100 octane was achieved by heavily mixing in ethanol and that threw off the cal enough to cause you issues. The car can compensate for e15, maybe e20 on stock boost- but anything over that she's likely to run out of injector. To get base 91 to 100 you're looking at e30-e40. Probably not enough injector to compensate for that

 

Hope fully not an issue here in PA. We have both 93 and 94 available. When I took my C8 to SEMA last year I struggled getting octane boost in the Vegas area as my C8 was modified with twin turbos and tuned for 93 octane.

 

Anybody else sees that the video is unavailable?

 

well if it was bad fuel, it shouldn't be working fine in the Mercedes, right? I mean pretty much the same exact fuel as I filled up fuel containers from the same pump I filled up the car with. I guess I'll try it again and see what happens, but this ONLY happened the one time i filled it halfway with 100 from the pump.

 

that's kind of why I was posting it in here. Kind of a heads up, kind of a question as to why. It never gave me any problems in my z06, but my ZR1 went basically into limp mode when I used it.

 

your other car might have bigger injectors, lower compression, more margin in the tune, not boosted, more knock resistant chambers- I don't anything about the MB in question and can't even begin to formulate a sensible or meaningful reply based on brand

Octane alone didn't cause your problems. Bad fuel or how they got that octane rating (mixing in E) are the most likely answers

its good to post your experience and results, esp as a CYA, but you don't seem too interested in finding the solution to the problem, just want to blame the fact it was 100 octane, cry wolf and warn others away from it

 

dude calm down im simply asking and all youre saying is it cannot be this even though every test ive done shows that is, in fact, this, with no other explanation. i was simply trying to share my experience of troubleshooting by pouring the exact same gas into my GLC63, not sure why you went into attack mode, but whatever. thanks for your "help" i guess. I am interested in finding the solution, but all you say is "bad gas" and then proceed to talk ****. Not sure how that helps at all. The bad gas works in every other car. I was trying to see if anyone else has tried this with their ZR1 to see if there is a problem with using 100 octane somehow since it didn't affect my z06 or Mercedes. I'm so sorry for inconveniencing you, please forgive me.

 

That might be all your read, but that's definitely not all I said. I have been the most invested and helpful poster in regards to your problem, and it wasn't until my last post that I said anything remotely considered "**** talking"

Working theories include (as previously stated)
-Bad gas (lol) to include too high of water content
-Bad gas (lol) to include too high E content
^ both the above will cause a lean condition, ESPECIALLY if injector margin is too low
-Not enough injector or tune margin in the ZR1 to accommodate less than perfect fuel conditions
-Compression ratio too high to accommodate for lean conditions
-Chamber design not tolerant of knock

You other vehicles may have been fine on the fuel for a plethora of reasons. Different quality of fuel at time of purchase, both cars have enough injector to manage higher E content, the Z06 for sure isn't boosted- so it's not dealing with that, chamber designs could be different, tunes are certainly different, load on engines are different... its a long list

100 octane by itself won't cause issues. Airplanes with 8:1 compressions run on 100 octane. The issue lies in how they achieved that 100 octane for your locality, or whether or not the fuel was contaminated with (most likely) water and how the ZR1 handles sub-par fuel conditions

Ways we can actually test this: data log injector duty cycle and compare to a/f ratio, test fuel for water and ethanol content

Either way, if the car knocked that hard- it wouldn't be a bad idea to pull plugs and check the gap. When engines detonate hard enough, they can collapse the strap of the spark plug. Probably been too long now, but another test you could have done would have been to pull a plug and look for speckling on it- another indicator of detonation

[/"**** talking"]