[ZLRob]

I have taken multiple datalogs of my car running 91 octane from multiple stations (the only one I have not tried yet is Shell), and on all reported log instances I have seen in some cases as much as 8- 9* of knock on my Z. It's not cool at all. The only thing that I find that helps it is adding in a can of Octanium by VP, or Boostane. Yes I have tried removing timing, static knock retard tables. It doesn't make a difference, as there is knock present even as low as cruising range, so it has been narrowed down to this junk California water gas.

With that being said, I'd really like to try and avoid having too dump in an octane booster every single time. California guys this post is for you (predominantly the Bay Area) where are you getting your fuel from? I can't seem to find 93 or 94 anywhere and I'd really like to try and get that stuff but it seems next to near impossible to find in my area. I'm really starting to wonder if having to tune for some ethanol is in my future.

Thanks in advance!

[radz28]

I've been running Shell, almost exclusively (literally, except for a single fill-up when driving up from LA, after picking the car up), while tuning a car, and from the same station, just to be as consistent as possible (knowing it will change, regardless).

The car has either gotten the orange (standard) Racegas Concentrate (whole can to a full tank), and we just started putting the volume necessary from Boostane Professional. They were trying to blend to get about 93-octane, and with a 2650 combination similar to mine, are running about 22* at WOT, through 6500 RPMs. That's on standard CA 91.

We messing with the MAT-tables now, and the car seems to be tolerating the changes. It'll hold 22* at WOT when it's into the 90s outside, so long as it hasn't been sitting, heat soaking. As soon as there is good airflow, though, it's not getting retard and or knock. I'm retarding the MAT retard well toward about 170*. The car does have a heat range colder plug, but we were getting these kind of good numbers at the end of Summer, last year, on OEM plugs.

LT4s are tuned from GM to run on 93, so you're just going to get knock here. There's nothing higher than 91, unless you find a special gas station that runs 100-octane at the pump. There's one by me, and that's literally the only one I know of in this region. You can try Boostane Professional, to blend to about 93. We just started using that one, and it seems good so far. You have the danger of contaminating cats' and emissions stuff, but these companies say it's not likely. We aren't getting a lot of orange from the exhaust tips, so we're blending pretty low, so I don't think it's going to be a huge issue, (hoping and fingers crossed), but Octanium is pretty emphatic about it being O2 sensor, cat', and emissions safe.

Blending might be your only option, unless you want to crack into the ECM and spend money on E'.

[beemer105]

use find93.com and blend to get there.

Or just start using 100 straight because you like the smell!!!

[ZL1 1LE]

I use this: https://race-gas.com/

[ZLRob]

Originally Posted by radz28

I've been running Shell, almost exclusively (literally, except for a single fill-up when driving up from LA, after picking the car up), while tuning a car, and from the same station, just to be as consistent as possible (knowing it will change, regardless).

The car has either gotten the orange (standard) Racegas Concentrate (whole can to a full tank), and we just started putting the volume necessary from Boostane Professional. They were trying to blend to get about 93-octane, and with a 2650 combination similar to mine, are running about 22* at WOT, through 6500 RPMs. That's on standard CA 91.

We messing with the MAT-tables now, and the car seems to be tolerating the changes. It'll hold 22* at WOT when it's into the 90s outside, so long as it hasn't been sitting, heat soaking. As soon as there is good airflow, though, it's not getting retard and or knock. I'm retarding the MAT retard well toward about 170*. The car does have a heat range colder plug, but we were getting these kind of good numbers at the end of Summer, last year, on OEM plugs.

LT4s are tuned from GM to run on 93, so you're just going to get knock here. There's nothing higher than 91, unless you find a special gas station that runs 100-octane at the pump. There's one by me, and that's literally the only one I know of in this region. You can try Boostane Professional, to blend to about 93. We just started using that one, and it seems good so far. You have the danger of contaminating cats' and emissions stuff, but these companies say it's not likely. We aren't getting a lot of orange from the exhaust tips, so we're blending pretty low, so I don't think it's going to be a huge issue, (hoping and fingers crossed), but Octanium is pretty emphatic about it being O2 sensor, cat', and emissions safe.

Blending might be your only option, unless you want to crack into the ECM and spend money on E'.

Oh I've already got it tuned on HP Tuners. The oranging thing is something I'm worried about but the tips on the back of this thing are black so even if they are orange I won't be able to tell, so that's an issue within itself.

For the light mods I got I have switched out the plugs on this thing to heat range 7 Ruthenium NGK plugs. I have had stellar success with them in my boosted truck and they have definitely helped with this car as well.. heat production is just high on these things. :(

The gas out here is totally trash and it has become apparent with this car. Lol.

Originally Posted by beemer105

use find93.com and blend to get there.

Or just start using 100 straight because you like the smell!!!

That was actually something I was looking at yesterday. I found nothing in my local area unfortunately. It seems the higher the octane the peppier and more powerful it gets.

[kropscamaro16]

i use only 76 or shell 91 and everytime i go to the track i use a bottle of this stuff


https://torcoracefuel.net/products/torco-accelerator

[Evansa22]

Either e85 or I've found 100 octane pump at a commercial fueling station near me. I Setup an account with them to use it but at $9 a gallon it's a little pricey compared to $3.70 for e85

[Coded4SS]

In Socal / CA gas all comes from the same place. We get bad batches of it. Name brand of the gas does not matter. I know people like brands and swear on brands but its literally the same stuff just stuff added. When I had my mustang tuned I was getting CEL's. I went to three stations all different locations/brands and it was the exact same thing in data logging. What fixed it? About a week or so later there was new shipments of fuel and it resolved it. The brand means nothing sometimes CA gets crap gas

[ZLRob]

So it sounds like the only solution here is to use 91 and add booster to it out this way of where we live unless we have access to race fuel. Which the stations are far and few in between.

[SFV1LE]

I've mostly been using my ZLE on track, and spending a lot on 101 to ensure it's at 93 or higher.

I also use VP 101 from local Chevron for the occasional canyon run, and there's an Amber Resources / Sawyer race gas depot in Van Nuys 3 miles from my house where I can get virtually any unleaded or leaded VP or F&L race fuel made in 5 gallon cans. So that's nice.

[Camaro1973]

Originally Posted by radz28

I've been running Shell, almost exclusively (literally, except for a single fill-up when driving up from LA, after picking the car up), while tuning a car, and from the same station, just to be as consistent as possible (knowing it will change, regardless).

The car has either gotten the orange (standard) Racegas Concentrate (whole can to a full tank), and we just started putting the volume necessary from Boostane Professional. They were trying to blend to get about 93-octane, and with a 2650 combination similar to mine, are running about 22* at WOT, through 6500 RPMs. That's on standard CA 91.

We messing with the MAT-tables now, and the car seems to be tolerating the changes. It'll hold 22* at WOT when it's into the 90s outside, so long as it hasn't been sitting, heat soaking. As soon as there is good airflow, though, it's not getting retard and or knock. I'm retarding the MAT retard well toward about 170*. The car does have a heat range colder plug, but we were getting these kind of good numbers at the end of Summer, last year, on OEM plugs.

LT4s are tuned from GM to run on 93, so you're just going to get knock here. There's nothing higher than 91, unless you find a special gas station that runs 100-octane at the pump. There's one by me, and that's literally the only one I know of in this region. You can try Boostane Professional, to blend to about 93. We just started using that one, and it seems good so far. You have the danger of contaminating cats' and emissions stuff, but these companies say it's not likely. We aren't getting a lot of orange from the exhaust tips, so we're blending pretty low, so I don't think it's going to be a huge issue, (hoping and fingers crossed), but Octanium is pretty emphatic about it being O2 sensor, cat', and emissions safe.

Blending might be your only option, unless you want to crack into the ECM and spend money on E'.

I've been helping him tune this thing. The guy he bought it from it was a disaster. Tune was a mess, unknown mods etc. He was getting knock over 9 degrees of retard, he was only making 7-8lbs of boost, we fixed that it was a bad bypass valve. Its now close to stock as possible, but hes got a 9.06 pulley on it, so hes making 12lbs max boost.



Even with timing low like 14-16 degrees it was still knocking on the 91.


With like 16oz or less of the vp octanium he has near him on a full tank all knock is gone, and i've got timing hitting 22 degrees at the top and 12lbs of boost.



The fuel over there must be just really bad.

[ZLRob]

Originally Posted by Camaro1973

I've been helping him tune this thing. The guy he bought it from it was a disaster. Tune was a mess, unknown mods etc. He was getting knock over 9 degrees of retard, he was only making 7-8lbs of boost, we fixed that it was a bad bypass valve. Its now close to stock as possible, but hes got a 9.06 pulley on it, so hes making 12lbs max boost.



Even with timing low like 14-16 degrees it was still knocking on the 91.


With like 16oz or less of the vp octanium he has near him on a full tank all knock is gone, and i've got timing hitting 22 degrees at the top and 12lbs of boost.



The fuel over there must be just really bad.

Yeah the car has been a huge mess, but I'm glad it is back to a level where you and I personally know what's going on with it.

HUGE thank you for your time and efforts Mike! Seriously. If it wasn't for you I have a feeling that I would have blown this motor up in short order from all the knocking.

At least moving forward I know what it is that I need to do as far as fueling is concerned and have several options at my disposal.

[radz28]

Originally Posted by ZLRob

Oh I've already got it tuned on HP Tuners. The oranging thing is something I'm worried about but the tips on the back of this thing are black so even if they are orange I won't be able to tell, so that's an issue within itself.

For the light mods I got I have switched out the plugs on this thing to heat range 7 Ruthenium NGK plugs. I have had stellar success with them in my boosted truck and they have definitely helped with this car as well.. heat production is just high on these things. :(

The gas out here is totally trash and it has become apparent with this car. Lol.

That was actually something I was looking at yesterday. I found nothing in my local area unfortunately. It seems the higher the octane the peppier and more powerful it gets.

Yeah - if you don't clean the tips, with a blend like I was talking about, and about some follow-up posts, you probably won't notice orange'ing. It will happen to the spark plugs, though, because of the metals they use in the boosters to increase octane. It's just going to happen, and it's those metals that can cause the cats' and sensors to go out over time, apparently.

Even LT1s knock, from what many have reported. That's just what we have to contend with, I guess...

On an aside, regarding the boosters: I'm a little concerned about the boosters, because I'm wondering if the metals they're using come out of the exhaust pipes, and actually burn into the rear facia.

I keep my car pretty clean, and it's garaged. But the last time I coated it, I noticed what looked like tiny burn-flecks in the clearcoat on the rear facia. I know that dust and other debris can be kicked-up onto the facia from regular driving, so I made the leap to this stuff, because it comes out of the exhaust so hot. It seems plausible, in my rationale, but I just wanted to throw that out there in case anyone else had any comments.

Originally Posted by Camaro1973

I've been helping him tune this thing. The guy he bought it from it was a disaster. Tune was a mess, unknown mods etc. He was getting knock over 9 degrees of retard, he was only making 7-8lbs of boost, we fixed that it was a bad bypass valve. Its now close to stock as possible, but hes got a 9.06 pulley on it, so hes making 12lbs max boost.

Even with timing low like 14-16 degrees it was still knocking on the 91.

With like 16oz or less of the vp octanium he has near him on a full tank all knock is gone, and i've got timing hitting 22 degrees at the top and 12lbs of boost.

The fuel over there must be just really bad.

Great news!!! Our gas must be garbage. I really haven't pushed the limits of timing. I bumped it up a couple degrees at a time, and just stopped at 22. We're at about 15-16-psi so far, and we just didn't want to over-rely on the additive, even though we are. toohighpsi said he was able to run about 22* at an 12.0 AFR, on our 91, and so that's what we were trying to model our max at. We just didn't want to have to run too much additive so we weren't killing emissions crap.

Originally Posted by ZLRob

Yeah the car has been a huge mess, but I'm glad it is back to a level where you and I personally know what's going on with it.

HUGE thank you for your time and efforts Mike! Seriously. If it wasn't for you I have a feeling that I would have blown this motor up in short order from all the knocking.

At least moving forward I know what it is that I need to do as far as fueling is concerned and have several options at my disposal.

The more options the better. If you're on the stock blower and long block, you might as well look into E', especially since you've cracked the ECM. That's my vote anyways. Supposing you have E' available...

[MartinLe]

"The more options the better. If you're on the stock blower and long block, you might as well look into E', especially since you've cracked the ECM. That's my vote anyways. Supposing you have E' available...

I have mentioned in other threads about the ease of blending E with whatever you get at the pump. I do not know about CA, but it is easy to buy a 55 gal barrel of E98 here in Oregon (I purchase mine from Tyree Oil and it is delivered to my house.). I read my E content and fuel level percentage off my Banks gauge. I have an ethanol blend app on my phone that is very straight forward. I add the required amount of E and head to the the gas station and tell them to add (yes, we cannot pump our own gas.) x gallons of premium. This has worked well for me. It might be worth a try for you.