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Every real race fuel has more lead than 100/130. Very high octane blends like C12, C16, Q16 are loaded with lead and are not leaving engine internals in a worse state than unleaded street fuels.
While I would agree that it eventually would render cats and 02s marginal if not unusable, when the engines using these fuels are torn down there are no "lead globules" on the spark plug electrodes. Some of the claims here are getting very hard to seriously take in.
It will destroy your cats. It creates hard lead deposits in spark plugs, piston tops, valve heads and chamber walls and it will void your warranty.
As for AVGAS 100/130, with the exception of Hawaii and Utah, it is not available in the U.S.
If you insist on AVGAS, try to find 91/96UL which is unleaded, but still has other problems using AVGAS in automotive engines such as slow burn times intended for engines with much larger cylinder displacement and lower operating speeds.
I think most that try to garner good information from this thread can easily find PDF files with information on the problems of lead contamination from aviation fuels with any search engine regardless of what some apparently clueless posters my try to proffer. We can only try.
So many carryover complaints from model years past keep being regurgitated. The current models work just fine. The A8 is lightning quick and learns quickly the shifting points of a particular track. The computer algorithms really are amazing.
Why not just use an auto and stay with left foot braking while keeping throttle loaded?
Let me just say I do understand that some can really enjoy the rev matching. But for me and others that are fairly proficient at heel/toe, admittedly some better than others, enjoy manipulating all the dynamics of a perfect downshift. Rev matching, by its very term, means doing the matching for you. You don't have to execute that part of the downshift, the program does it for you. I do find that just a little pretentious. However, I have friends with compromised ankles that can't really do heel/toe that well. It would work well for them.
There you go, talking about old Painter! Yes for a left ankle that has been broken 3 time, rev match is cool!
Also, the great improvement with dog ring racing transmissions is left foot braking to keep the suspension loaded.
I think most that try to garner good information from this thread can easily find PDF files with information on the problems of lead contamination from aviation fuels with any search engine regardless of what some apparently clueless posters my try to proffer. We can only try.
You are giving out incorrect information sir. Yes it will coat cats and o2s but these lead globules are not something you see in automotive engines running highly leaded fuels. It is apparent from your posts that you don't have first hand experience inside these engines, if you did you wouldn't be repeating the same "information".
And do not disrespect me by calling me "clueless" in a passive agressive manner.
You are giving out incorrect information sir. Yes it will coat cats and o2s but these lead globules are not something you see in automotive engines running highly leaded fuels. It is apparent from your posts that you don't have first hand experience inside these engines, if you did you wouldn't be repeating the same "information".
And do not disrespect me by calling me "clueless" in a passive agressive manner.
Don't pretend you know what you are talking about when it comes to leaded aviation fuel. You don't.
That's what you get when setting records in most every configuration of racecar for the last 4? 5? decades! If I only knew what you have forgotten.
You about done?
I don't care about your track accolades. It is plainly obvious to me that mechanically and technically you don't actually know anything. The reality is that if you did, you wouldn't be posting false TECHNICAL information.
Have fun polishing your bowling trophies. Oops--I mean "hardware"
PS: PLEASE don't list for us with all the "wins" you have had over the years as you are planning to do to "win" this idiotic back and forth. It has ZERO to do with the insides of an engine.
I don't care about your track accolades. It is plainly obvious to me that mechanically and technically you don't actually know anything. The reality is that if you did, you wouldn't be posting false TECHNICAL information.
Have fun polishing your bowling trophies. Oops--I mean "hardware"
PS: PLEASE don't list for us with all the "wins" you have had over the years as you are planning to do to "win" this idiotic back and forth. It has ZERO to do with the insides of an engine.
You do realize his comment was in reply to Jim (Painrace) who has an extensive racing career and is a heck of a nice guy. It wasn't about himself.
I don't care about your track accolades. It is plainly obvious to me that mechanically and technically you don't actually know anything. The reality is that if you did, you wouldn't be posting false TECHNICAL information.
Have fun polishing your bowling trophies. Oops--I mean "hardware"
PS: PLEASE don't list for us with all the "wins" you have had over the years as you are planning to do to "win" this idiotic back and forth. It has ZERO to do with the insides of an engine.
Apparently your reading comprehension isn't that great.
He was referencing Jim Painter (Painrace) who's had a successful racing career.
I don't care about your track accolades. It is plainly obvious to me that mechanically and technically you don't actually know anything. The reality is that if you did, you wouldn't be posting false TECHNICAL information.
Have fun polishing your bowling trophies. Oops--I mean "hardware"
PS: PLEASE don't list for us with all the "wins" you have had over the years as you are planning to do to "win" this idiotic back and forth. It has ZERO to do with the insides of an engine.
My sincere apologies then. I know when my foot winds up in my mouth, this is one of those times. I was responding to Southern Son specifically.
Back to the original subject, let me add a little data to this discussion. Below is some PDR data of a friend with an A8 ZR1 (Red) and me in an M7 ZR1 (Blue). The traces from top to bottom are accelerator, speed, and longitudinal acceleration. Now what’s neat about this is that you can clearly see in the Long G trace that the acceleration is pretty much the same until ~115 MPH but after than the manual definitely is pulling harder. However, every time I go to shift in the M7 the car stops accelerating while the A8 continues and the net effect is that on each shift the A8 gains ~2 MPH which is then carried forward. The result is that while the M7 started on the straight with a 2 MPH advantage by the end the straight where I lift first the M7 now is 5 MPH slower.
I’ll have to try and work on my shifts and try the same test using no lift shift but to be honest I do not feel confident doing a NLS on anything other than 3-4 without accidentally hitting the wrong gear.
As far as those articles there is nothing about the comparison to the A8 except the chart showing ratio differences. You stated that the A10 shifts faster and is in the powerband more. I don't see that either. The LT5 has a fairly wide power band. Also, the articles I have seen state the A8 is faster in shifts than the PDK's. As far as the comparison to faster shifts than previous trannys it appears to be comparing previous autos available in the camaro. Both articles are from 2016. But, if you know of a direct comparison to the 2019 ZR1 A8 that would be interesting. As far as fit of the tranny, the size is the same as previous autos.
Stop reading GM biased BS. A8 does not shifter faster than a pdk. The gm a8 is possibly the slowest shifting 8 speed transmission in a high hp car. Why do you think a stock c7z can lose to a stock hellcat, despite the hellcat weight over 900lbs more? Also, the zr1 loses to the Ford gt despite the 100hp and huge tq advantage. Lol I love people who quote biased articles. They do not live in the real world.
Gm really screwed up not putting a dct in the zr1. It will be hilarious if the new gt500 smokes the zr1. I think the zr1 is bad *** but GM should have went out with a bang for the FE zr1 and put a dct transmission in it.
Every real race fuel has more lead than 100/130. Very high octane blends like C12, C16, Q16 are loaded with lead and are not leaving engine internals in a worse state than unleaded street fuels.
While I would agree that it eventually would render cats and 02s marginal if not unusable, when the engines using these fuels are torn down there are no "lead globules" on the spark plug electrodes. Some of the claims here are getting very hard to seriously take in.
That you use the term "lead globules" has me thinking you may never seen a spark plug with deposits left by combustion of TEL, but opining is a waste of our time, here.
Why not prove me wrong by doing the following:
1) AVGAS 100 has 4.25-grams of tetraethyllead (TEL) per gallon. AVGAS LL100 has half that, or 2.125-g/gal. TEL. For reference AVGAS 115, if you could find it, has 4.85-g/gal. TEL. Post the amount of TEL in those VP fuels you cited?
2) Post pictures of the spark plugs, piston tops and combustion chambers from these leaded-fuel racing engines you have disassembled.
3) Tell us how these engines were raced, what kind of leaded fuel they used and how long they were run before they were disassembled.
4) Volunteer to be one of the first to run your LT5 on AVGAS LL100 for three months then pull a spark plug or two, shoot some close-up photos and post them. Even better...after that three months on low lead 100, bring your car by my shop and I'll borescope the engine. We'll examine the imagery together and see if there are any deposits from combustion of TEL and, heck, just for laughs we'll pull an O2S and borescope the front of one of your cats.
Last edited by Hib Halverson; 05-25-2019 at 11:40 AM.
Back to the original subject, let me add a little data to this discussion. Below is some PDR data of a friend with an A8 ZR1 (Red) and me in an M7 ZR1 (Blue). The traces from top to bottom are accelerator, speed, and longitudinal acceleration. Now what’s neat about this is that you can clearly see in the Long G trace that the acceleration is pretty much the same until ~115 MPH but after than the manual definitely is pulling harder. However, every time I go to shift in the M7 the car stops accelerating while the A8 continues and the net effect is that on each shift the A8 gains ~2 MPH which is then carried forward. The result is that while the M7 started on the straight with a 2 MPH advantage by the end the straight where I lift first the M7 now is 5 MPH slower.
I’ll have to try and work on my shifts and try the same test using no lift shift but to be honest I do not feel confident doing a NLS on anything other than 3-4 without accidentally hitting the wrong gear.
I have driven three different Corvettes with either TR6060s or TR6070s and used Launch Control and no-lift-shifts. I had no problem missing gears. The only problem I had was the first time I tried launch control, my reflex instinct was to lift as I left. As soon as you lift launch control is disabled. The second time I tried I got it right.
The three Corvettes were a pre-production 2012 Z06/Z07, my own production 2012 Z06/Z07 and a 2018 Grand Sport manual with Z07.
In my opinion, unless the TR6070 in your C7 has shifter that's FUBAR, clutch hydraulics which are f#&ed-up or a transmission what has some shift-related problem, you're not going to have trouble as you are an experienced driver, so go for it! Try some acceleration tests with Launch Control and no-lift-shifting. The 2-3 shift is pretty easy as long as you just push the shifter forward and let the shifter mechanism move from the 1-2 gate to the 3-4 gate.
Last edited by Hib Halverson; 05-25-2019 at 11:40 AM.
Ok. Back to the discussion of gasolines, knock retard and KR's effect on powertrain cooling during track use of ZR1s with 8L90 automatics.
Two days ago, I ran some more tests. First, I mixed-up some 93-octane gasoline by combining 7-gal of 91-oct with 2-gal of 100 unleaded. Seven gallons is about ⅜-ths of a tank of fuel in a C7, so I went over to my local 76 station and filled to the ⅜-ths mark with 91-oct. Then I went back to the shop and added two gallons of 100-unleaded which results in gasoline with about 93-oct. Lake Speed Jr., Driven Racing Oil 's R&D manager, told me the recommended treat rate for their "Defender+Booster" is 1:192 but that can be increased to 1:128 for maximum effect while still retaining the product's ability to have little or no effect on O2Ses, spark plugs and internal engine parts. I had nine gallons of my homemade 93-octane in the tanks so I added nine ounces of "Defender+Booster. I drove around for a while to make sure the fuel and the booster were totally mixed.
Then I went to the same test venue I used before and made five 2000-RPM to rev-limiter passes in fourth gear. Once again, the air was really good. I was at sea level with an IAT of 72° There was still just a little knock retard around peak torque but it was 1° or 2° which stepped down to zero. From the high-mid-range to 6600-RPM there was no knock retard at all. On the best run the most KR was a 1.3° "hit" at 3350 rpm which stepped down to 0.5° KR at 4300 (in a practical sense, none) then ran KR-free to 6600 rpm, so my opinion is that Driven Racing Oils "Defender+Booster" can take 93-oct gas to about 95-octane. That's not as impressive as what many MMT-based boosters can do with 87-octane gas, but it's about par-for-the-course with an MMT-booster using a conservative treat rate in 93-oct. gas. Plus, with Driven's new octane booster, you get a product that's formulated with detergents specifically intended to keep oxygen sensors, spark plugs, engine parts and cats free of MMT residue.
My guess is that in good air on a cool day 93 pump gas with some of that Driven Racing Oil octane booster would be good for track use. You might have a little KR but nothing great enough to retard the spark such that the powertrain would run warm. On hot days, an octane booster would not be effective. You'd need at least a 1:2 mix of 93 and 100 unleaded race gas and maybe even straight 100-unleaded to be KR-free in track use.
Last edited by Hib Halverson; 05-25-2019 at 11:43 AM.
Stop reading GM biased BS. A8 does not shifter faster than a pdk. The gm a8 is possibly the slowest shifting 8 speed transmission in a high hp car. Why do you think a stock c7z can lose to a stock hellcat, despite the hellcat weight over 900lbs more? Also, the zr1 loses to the Ford gt despite the 100hp and huge tq advantage. Lol I love people who quote biased articles. They do not live in the real world.
Gm really screwed up not putting a dct in the zr1. It will be hilarious if the new gt500 smokes the zr1. I think the zr1 is bad *** but GM should have went out with a bang for the FE zr1 and put a dct transmission in it.
So I shouldn't believe printed material that are official releases but simply believe your unsubstantiated opinion. Got it!
You know, the good thing about a higher education is that it teaches you to never have a singular plane of thought. All subjects have many layers or dimensions. Never stop any train of thought when you think you have reached 'good enough'. As we used to say in air traffic control, " incomplete information is worse than no information". The paddle shifting of the A8 is slow. The full automatic mode is lightening fast. I know, I own one. Do you?
Last edited by SouthernSon; 05-25-2019 at 08:36 AM.
So I shouldn't believe printed material that are official releases but simply believe your unsubstantiated opinion. Got it!
You know, the good thing about a higher education is that it teaches you to never have a singular plane of thought. All subjects have many layers or dimensions. Never stop any train of thought when you think you have reached 'good enough'. As we used to say in air traffic control, " incomplete information is worse than no information". The paddle shifting of the A8 is slow. The full automatic mode is lightening fast. I know, I own one. Do you?
Check YouTube, it is more real then a printed article from GM. Or maybe race your cars against other cars. Wait nvm, you sound like a waxer quoting articles and magazine lap times.
The reasons GM did not put a "DCT" in the ZR1 are three
1) The cost of developing a new transmission for use in only 2500 or 3000 cars would have been obscene. Keep in mind that not only would the transmission have to be developed but the powertrain would also have to be Federally-certified which, alone, costs hundreds of thousands and maybe a million or more.
2) If said DCT would have ended up longer than the existing 8L90 or the TR6070, GM would likely not invest the money to change the car's wheelbase to accomodate a longer transmission which is the same reason the 10L90 was not used in a Corvette.
3) The marketing politics of introducing a DCT in the ZR-1 rather than in the C8 would probably have precluded doing so.
Lastly, in my opinion, it's going to take more than a dual-clutch automatic to make a car with 35 less horsepower and 100 pounds more curb weight quicker than a ZR1.
Last edited by Hib Halverson; 05-25-2019 at 03:36 PM.
05-22-2019, 01:26 PM
So many carryover complaints from model years past keep being regurgitated. The current models work just fine. The A8 is lightning quick and learns quickly the shifting points of a particular track. The computer algorithms really are amazing. 
