What is everybody running for fuel in their 289s and 428s ?
I haven't had much luck yet finding the right octane booster..... but today ran 50/50 pump 93 and Sunoco 110 leaded race fuel so in essence the mixture was 101.5 octane with some lead and netted excellent results. It was noticeably happier. I don't mind doing this once in a while.... it would get a little expensive if it were a full time habit, but I just wanted to know what you guys are using and what kind of results are you seeing.
Thanks.
BG
I do what you do. VP or Sunoco. 110 with 93 or straight 110. It runs like a different car on the race fuel and the slightly rich idle from the dual quads doesn't bother you. I also noticed the fuel percolation issues went away with the race fuel.
That's a loaded question... Most street engines running less then 10 to 1 compression ratio run just fine on pump gas. When you head on over to your race gas dealer he will have many choices for you! For starters they will ask what you have, nitrous, blower, turbos, high compression pistons etc. This will eliminate many choices if you don't fall into those categories. Next will come how do you drive your car? Do you want to race it, constant high rpm use, street performance, leaded , unleaded, oh my head is spinning. 100 unleaded is a good starting point for most street cars. VP- TRICK - SUNOCO all good stuff!
A local co-op that carries ethanol free fuel just started carrying VP 110 leaded. Definitely going to give it a try in the 66...
The best I can do at the pump in this area is 91 ethanol free. The other best I can do is 110 leaded. It helps, but it is not what it should be. I am hoping this summer I can find better.
I think Watkins Glenn may have some good stuff, but that is over an hour drive, no point in going up unless I take several cans and fill them up. Too bad, because if is a fun drive with the exception of the roads! LOL
here in cali, 91 ethanol burns black and sooty exhaust whereas the 110 leaded sunoco is charcoal gray on the exhaust tips. but expensive
Quote from: 67 GT350 on March 19, 2020, 08:35:48 PM
The best I can do at the pump in this area is 91 ethanol free. The other best I can do is 110 leaded. It helps, but it is not what it should be. I am hoping this summer I can find better.
I think Watkins Glenn may have some good stuff, but that is over an hour drive, no point in going up unless I take several cans and fill them up. Too bad, because if is a fun drive with the exception of the roads! LOL
Just bring some cans. As many as you want.
It's available at the track,....probably off limits unless ur there for an event, but one of the gas stations on the way in did carry race fuel and I'm sure still does. On route 14.
93 pure gas does well in my 427, haven't needed additional octane. A small amount of Avgas 100LL would bump the octane if you felt you needed it, but the excessive lead in Avgas would not be good in the long term. There are plenty of octane booster's out there, but since I don't need them I haven't researched them.
All of my cars I run 93 except the 55 Chevy and the B9 which run 110/112
Quote from: 67 GT350 on March 19, 2020, 08:35:48 PM
The best I can do at the pump in this area is 91 ethanol free. The other best I can do is 110 leaded. It helps, but it is not what it should be. I am hoping this summer I can find better.
I think Watkins Glenn may have some good stuff, but that is over an hour drive, no point in going up unless I take several cans and fill them up. Too bad, because if is a fun drive with the exception of the roads! LOL
It's not that bad. 13 to 86 to 14.. You just get hung up behind either old people in no hurry, deer dodging or tourist in the Glenn or visiting the gorge.
I am not sure which one is the worst..lol
Quote from: EdwardGT350 on March 19, 2020, 09:06:36 PM
here in cali, 91 ethanol burns black and sooty exhaust whereas the 110 leaded sunoco is charcoal gray on the exhaust tips. but expensive
Yep, and I love the smell of the 110 leaded race gas. It's even fun to just fire the car up in the garage (with the garage doors open, of course.)
Both of my stroked 427s love the higher octane. The only downside to running leaded 110 in the cars when merely street driven (other than the $/mile equation) is the possibility of fouled plugs. In my experience, the "good stuff" us best utilized when you can really romp on the car for quite a while...like a track day.
Thanks guys, all good info. Anyone found an octane booster that works well and / or they like ?
BG
Toluene- at the hardware store. Thank me later... ;)
Quote from: 427heaven on March 19, 2020, 11:28:04 PM
Toluene- at the hardware store. Thank me later... ;)
I tried Toluene at the hardware store and it didn't work out for me. I don't know if this is the best alternative out there but I have used Octane Supreme (just google the name)for years and have found it works good for may situation.
If I'm in a situation where there's no EtOH-free fuel around I use Klotz KL-602 octane booster/stabilizer.
I am using 89 E free fuel with stabilizer and no boosters. 6S2187 is tuned for it and runs very nicely. See page 612 of the new 1966 Shelby Registry. No complaints. 8)
How much toluene should you mix with 10 gallons of 91 no ethanol pump gas to get, say, 100 octane?
The question to me is simply why use 110 if you don't need it?
Octane rating, the higher you go, is simply the resistence to "dieseling" of the fuel. Dieseling being defined as combustion without an ignition spark and ignition by compressing the fuel.
High octane fuel does not produce more power. In fact, lower octane fuel produces more heat calories per unit, making more power.
In addition, higher octane is usually obtained by adding compounds such as lead. That will add a white crusty deposit to both the spark plug electrodes AND the valves and valve seats.
It also creates an acid compound that initiates an internal process of rotting the exhaust system that otherwise would not occur.
ONE of the strange occurrences that you will notice in running racing gas is that the engine will IMMEDIATELY idle lower. For instance, if you were set to idle at say 950 rpm with pump gas, the engine will immediately drop down to like 550 or 600 rpm.
Why? The higher octane fuel produces less heat calories, i.e., less energy and the idle is showing the percentage of loss of power at idle.
At one time, when leaded gas was the fuel you got at any retail fuel supplier, one could walk along any street in a city and touch the dust laying along the curbside with your finger. That dust was nearly 100% lead that had settled from the exhausts of motor vehicles.
Of course I will also point out that when I started school and we were learning to write, the pencils that we were given were lead pencils. Yea, the bad stuff, so no one is innocent here, except maybe 5 year olds that were learning to write with poison sticks finished in lead based paints?
The teacher told us not to lick the tip, even though that made the pencil easier to write with and if we were good and if our hands started to itch we could go to the sink and wash our hands until the itching stopped.
i'm not accusing anyone of anything. Just explaining what I know within the limitations of my obviously lead damaged brain and nervous system?
UNLESS you ARE running 12.0:1 (sometimes as low as 11.0:1 to be fair) you positively do not want even 103 leaded gas in your cars system. If you think you do then unfortunately you have not correctly analyzed the engineering here.
If you like the smell of it, just get a gallon and take the cap of the container and sniff it. Tires burn well too once you get them going. If you live in an apartment, put one in your barbecue and light it up.
It all depends on your background. To me, these smells just invoke memories of burning cities on fire from being under military seige. That is of course without the smell of the dead corpses of people and animals lying in the streets. That one's a real treat that you shouldn't miss? However there still are those that genuinely love the smell of napom in the morning. I don't, but that's just me? ;D
I do admit that as a kid I did love the smell of the fumes of the gas as it was being pumped into Dad's gas tank and loved the woosey feeling it created. It was a cheap high?
I had a case of Moroso octane booster. Four one gallon cans. I was amused by the red skull and crossbones printed on the cans and the warning, "wear gloves in handling this compound. Do not get it on your skin. It will be absorbed through the skin and will block red blood cells from absorbing oxygen from the lungs". :o
It went on to state, "in case of contact, get medical attention immediately", and described the effected area as turning purple from asphyxiation of the body tissue in that area. I don't know if that meant that you just killed your hand that turned purple, but maybe?
I gave it away to one of the local racers with a 65 GTO. I told him he had to get his own gloves. ;D
For folks in the Texas area, check out your local Buc-EE's. They have 91 octane ethanol free fuel. I just filled both old Mustangs with it and added some Sta-Bil. It's priced the same as their 93 octane (which has ethanol).
Quote from: rkm on March 20, 2020, 07:17:18 AM
How much toluene should you mix with 10 gallons of 91 no ethanol pump gas to get, say, 100 octane?
In reading Dougs response is pretty accurate, I didn't want to write a thesis on the subject. A quick overview of what you need would be the shade tree mechanics way of testing. To understand THERMODYNAMICS and how it relates to engines is a simple listening to when your engine starts to rattle or ping. For starters you need to start off with the highest octane gas you can start with for obvious reasons, then you will need to adjust your timing to advance or retard the timing as a basis for testing. If you don't hear anything you don't need to continue and waste your money on additives. If you do, add about 1 ounce per gallon of gas this will fix most street engines pinging problems. Add or subtract as needed to find the sweet spot. ;)
Some of the aforementioned rules apply until you start with power adders. The custom grind cam I have was designed to assist with this issue. However, even with the new engine and my reduction to about 9.9:1 I still have an issue without running a minimum of 93. The new aluminum head design seems to be a bit more helpful with flame propagation and also allows me to drop the advance back from 38 to 36. I did note the fact that the economy is reduced with retarded timing settings. Any forced induction nullifies much of the previous argument.
Quote from: The Going Thing on March 20, 2020, 11:50:22 AM
Some of the aforementioned rules apply until you start with power adders. The custom grind cam I have was designed to assist with this issue. However, even with the new engine and my reduction to about 9.9:1 I still have an issue without running a minimum of 93. The new aluminum head design seems to be a bit more helpful with flame propagation and also allows me to drop the advance back from 38 to 36. I did note the fact that the economy is reduced with retarded timing settings. Any forced induction nullifies much of the previous argument.
The aluminum heads seem to work as well or better at 32-33 degrees total. It kind of makes sense to me since the Pro-Stock BB GM's were backing off on timing through the traps to increase top speed.
Aluminum heads only loose more power through the aluminum due to thermodynamics.
The old "rule of thumb" was that you needed to increase static compression ratio 1.1:1 with an aluminum head to make equivalent power of an iron head.
That has almost nothing to do with the octane necessary to resist detonation since that is the effect of cylinder pressure, not thermodynamics.
I was not impressed, helped by or convinced that leaving the exhaust open longer will bleed off cylinder pressure in amounts significant enough to run 93 unleaded in an 11.5:1 engine. Been there. Done that. Didn't work for me.
What Keith is correct to point out here is that the flame travel caused by the shape of the combustion chambers does effect cylinder pressures.
In the case of Fords, seemingly you can run a 10.5:1 289 on 89 regular all day and at the track, whereas the Cleveland and the FE are just "mutha's" on demanding high octane fuels even at that 10.5:1.
So the answer is, every time you mess with these engines in changing something, even as simple as a cam duration and overlap, you might change the need for fuel octane?
Adding a lead compound to the fuel is the simplest way to increase octane.
During the two fuel shortages of the '70s, the fuel manufacturers "bitched" that in order to make even 103, it had to come off of "the top of the barrel". I'm sure that's a "refiners term" used to scare the crap out of politicians?
The laymans explanation I got from Exon (I did work for the CEO at the time, he was an engineer, not an MBA...amazing right?) was that for every gallon of high octane gas he could make 10 gallons of regular.
At this point he got nasty and said WTF are you to be so demanding? At this point I took the men off the job and let his skylight holes leak water all winter until he asked me to come back in May...nicely?
I think he got letters telling him to FO. I have no idea how his personal address got out to the public? What a shame? ;D
I agree with you, Doug. The standard FE chambers leave much to be desired. It's compounded when the quench isn't right. On the convertible with the turbocharged six there is actually a sticker in the gas door that the minimum is 91 octane. The new lincoln, on the other hand, seems completely happy with regular.
Not an FE, but my 13:1 351C likes Sunoco 110. A lot! John Barnes told me when I bought the car that it didn't "need" 110 but he liked the smell. Me too! Better than most perfumes but I can't get my wife to splash some on her neck. :(
But being a stingy Irishman, I have found that cutting the 110 with 25% 89 non-ethanol (which supposedly tests out at 90-91 but they don't want to re-label the pump) works just about as good, smells good and costs a little less per mile. By the way, I'm paying less than $9/gallon for the 110 fuel, so it's relatively inexpensive here. If I went to the race track - $12-$15 per gallon.
Quote from: kjspeed on March 20, 2020, 05:01:29 PM
Not an FE, but my 13:1 351C likes Sunoco 110. A lot! John Barnes told me when I bought the car that it didn't "need" 110 but he liked the smell. Me too! Better than most perfumes but I can't get my wife to splash some on her neck. :(
But being a stingy Irishman, I have found that cutting the 110 with 25% 89 non-ethanol (which supposedly tests out at 90-91 but they don't want to re-label the pump) works just about as good, smells good and costs a little less per mile. By the way, I'm paying less than $9/gallon for the 110 fuel, so it's relatively inexpensive here. If I went to the race track - $12-$15 per gallon.
I had 11.8:1 TRW pop up pistons in the iron closed chamber heads. On pump gas the detonation got so bad that the engine would just shut itself off if you suddenly wot it.
Then I tried the open chamber heads and the engine became a slug which signed it's own death warrant.
Pump gas in Europe is about $9 a gallon. They pay per liter what we pay per gallon. I'm not sure if 110 is anywhere but at a race track in Europe. It's not at the pumps because of the lead.
When I was in Madrid Spain in October the octane rating for regular was 92, the premium was 95 and Super was 97. It was damn expensive too.
It was about 7.50 U.S. per gallon. Spain and France were much less expensive than in London. The taxes on fuel in the U.K. are horrid.
Quote from: The Going Thing on March 22, 2020, 02:26:22 PM
When I was in Madrid Spain in October the octane rating for regular was 92, the premium was 95 and Super was 97. It was damn expensive too.
It was about 7.50 U.S. per gallon. Spain and France were much less expensive than in London. The taxes on fuel in the U.K. are horrid.
What octane rating system were they using? Their 97 is our 93?
I remember Sunoco 260 was 103 under the old system. That stuff was purple and had that nighty-night smell to it. I'd get really light headed pumping it. That's when I liked full service stations except they'd always have a problem with the fuel filler and scratch up the Shelby decal on it.
Most would try to twist the thing off. I guess a quick fill pop open was too abstract of an idea?
Quote from: The Going Thing on March 22, 2020, 02:26:22 PM
When I was in Madrid Spain in October the octane rating for regular was 92, the premium was 95 and Super was 97. It was damn expensive too.
It was about 7.50 U.S. per gallon. Spain and France were much less expensive than in London. The taxes on fuel in the U.K. are horrid.
You were getting screwed even further. Europe uses the research method for octane rating which produces a higher number than the motor rating method. Here in the US they use both methods and average the results to post on the pump. Europe also ran baby motors with high compression so the octane needed to be higher. The downside was it produced more CO.
So ideally for my stock 10.5 / 1 SB..... adding some type of lead additive is best for 93 pump gas rather than an octane booster ? Anybody recommend a good product ?
As always, thanks in advance.
Bob,
Redlines lead additive has been used amongst the '20's thru '50's car crowd for years, one bottle treats 20 gallons of fuel. Shop around I think one can find it cheaper than Redlines link below. Your car should run fine on 93 octane, especially the kind without the corn additive. :)
https://www.redlineoil.com/lead-substitute
Quote from: oldcanuck on March 26, 2020, 10:01:27 AM
So ideally for my stock 10.5 / 1 SB..... adding some type of lead additive is best for 93 pump gas rather than an octane booster ? Anybody recommend a good product ?
As always, thanks in advance.
Be advised that an advertised 10.5:1 289 isn't. If you measure and calculate the ratio, you will see it's actually about 9.5:1. That's one reason they will run fine on pump regular.
An actual 10.5:1 289 is going to be tough to start hot on a stock starter.
I don't run leaded fuel. There are a lot of myths circulating about leaded fuel. The compression and lack of overlap with stock cams raises static compression which necessitates premium fuels to avoid detonation and engine damage.
VP sells Muscle Car Fuel. Leaded, stabil, and 95 octane.
Most of the specialty fuels here are VP or Conoco. 110 being the most common. In So Ca I was on staff at Chino Air Museum. You could fill five-gallon containers, or your vehicle with the 100 octane aviation fuel much less expensively than any race fuels. There was a Philips 66 station that also had 100 at the pumps back in the '90s. I miss the simple times.
10-25% 110 race gas or 100LL av gas is usually cheaper than and better than "octane boosters". Be SURE you need it first. I did some drag strip testing on my 408W in my daily driver '67 Ranchero. I had tuned it on the engine dyno for use with 87 octane before installing it in the car. Took it to the local 1/8th mile strip and ran 8.0s or about 12.4 1/4. Went back the following week with 91 ( near identical weather conditions and track prep. Slowed down to 8 teens and lost 2 mph. Went back the following week with 87 again and was back to 8.0s. Could I have tuned around it? Maybe but there was obviously no need for more octane in my case. Now in the case my GT350 with it's 11.5cr drag race only engine I wouldn't think of anything less than 110.
Randy
Here's the down side to running AV GAS. While it does have a higher octane rating your car wont perform any better. Your car wont rattle and knock, but it wont run like a scalded dog either. I used to fill up at all the local airports back in the day for so called street race enhancement fluid. One day I went with a buddy for some DYNO time I thought what a waste of money. A little shop from the way back machine was BOB JENNINGS dyno service, and in this shop were some big hitters in the SO CAL racing scene. I was proud to share that I knew how to get more performance on the cheap and they said oh yea how do you do it? AV GAS. In a kind way they laughed and said you cant gain much that way. I inquired why not? The very well heeled experienced engine guy said that while it has anti knock properties in it, the design of this fuel is designed for high altitude and constant rpms like 3000 rpm. With todays technology they have a fuel available for every application. If you went to ANY major motorsport race in the world and asked do you guys run AV GAS ? The answer would be NO! Everyone knows about it but it wont help engines that are needing different fuel components to maximize horsepower and reliability for their engine combos. Hope this helps a little-
I appreciate what you were told. What you heard is "part" of the story and not false. "Some" of the rest is , no highway taxes are paid on it ( the biggest reason), it has lead so it's technically illegal. The formulation is not "ideal" for a racing engine , no question about that.
Years ago I used to use the "green" AV gas . This was before the reformulation to "blue" Low Lead 100. When it changed I asked a friend who was a chemist for Conoco in the Santa Maria area regarding me still using it. He suggested that it should be mixed with pump gas to no more than 50% and not used above 11-1 static compression. "He" claimed that the additive package WAS altered and not "happy" at sea level in undiluted form. Only the "purple" ( military helicopter fuel) was still OK to use. I quit using it at that point.
My current fuel of choice for my racecar is Sunoco 110 , which "I" feel is better than VP.
Randy
I spent quite a bit of time at Jennings' Dyno Shop in the SF Valley in the 1980s. Bob was a great guy. Very knowledgeable and willing to share his expertise.
You never knew who would drop by the shop. Like 427heaven said, a lot of big name racers and engine builders. Plenty of magazine articles were done there, and the cars put on the dyno rollers.
Bob hung onto his shop until the bitter end, fifteen or so years ago, when no one needed (so it seemed) a vintage dyno shop with an old guy at the helm, in a kinda grimy little industrial strip in the San Fernando Valley. Too bad. Bob passed away several years ago.
A good friend still stays in touch with Bob's son Nick. He's in the movie car business, wrenching on many of the vehicles in today's action films.
Quote from: CSX 4133 on March 26, 2020, 12:02:18 PM
Bob,
Redlines lead additive has been used amongst the '20's thru '50's car crowd for years, one bottle treats 20 gallons of fuel. Shop around I think one can find it cheaper than Redlines link below. Your car should run fine on 93 octane, especially the kind without the corn additive. :)
https://www.redlineoil.com/lead-substitute
Steven,
Thanks..... I'm not aware of anyplace around where we live that sells 93 octane without ethanol. There are some Weigle's that sell 100% gasoline here but only 89 octane as far as I know. There is a Pilot that has 110 pump leaded race fuel, buts that's over in Roane County.
BG
Bob,
Here's one...
https://www.pure-gas.org/station?station_id=9641
pure-gas.org has a list by city if this one doesn't work. Do you know the location of the Pilot selling 110?
One thing about 110 that I noticed wasn't mentioned, is that you need to store it in a certain way.
You need to store it in a container that is sealed tight against the atmosphere. Some of the octane modifiers added to it will evaporate and you will loose some of the higher octane if you don't.
In the case of a Mustang, you can't store it in the cars gas tank if it has a vented cap. It needs to be completely sealed.
Pump unleaded is much less susceptible to that.
Here, we used to buy VP in 50 gallon drums. You would put a hand pump on the drum and just pump in maybe 5 gallons at a time into your tank.
Being in NY though was a problem, sort of. The gas was in NJ and all of the river crossings are restricting crossing with the volatility of the fuel in the drum. The bridge authority considers it an explosive device. Normally you can get a drum delivered by the seller but in this case they can't cross the bridge.
So the solution was to go pick it up yourself in an enclosed Econoline, drive it across at your own perill. If the van blew up, it wouldn't matter to you because you would be dead anyway.
I'll tell you also that even though the drum is sealed closed, you still smell the fumes. Don't worry though. If you are pretty young and healthy, you'll only be sick for a couple of days and your appetite for food will normally come back. NP. ;)
You need a certain type of property to keep it at and it would be better to store it in a concrete block building in an industrial zoned area. You can not by law keep it in a residential zoned area. The place will smell like a gas station where you keep the drum and really is doubtful you should store it around an area with any living thing within about 50 feet of it?
You MAY also find that when the drum is empty, you can't get rid of it anywhere. You're stuck with it?
Lots of bad information there Doug. Since when is it not legal to store gasoline in gas cans anywhere? It isn't.
My 428CJ seems happy enough on super unleaded. The pure gas / no ethanol kind is available everywhere here in Tulsa.
Meanwhile the 427 in my other car is not happy on anything less than a 50/50 mix of race gas and super unleaded. It really has 10.9:1 compression - it is factory stock - so I get 110 octane VP in 5 gallon cans. Typically I do not run below 1/2 tank so 3 gallons of race gas and 3 gallons of pump gas and it's happy. I drive my cars maybe 1000 miles each per year so it's not a lot of money to keep the one full of the fuel it likes.
Avgas is great stuff too but you have to run a higher percentage in order to get the same results because it is only 100 octane while VP110 is 110 octane. Back when I worked on airplanes for a living I would occasionally get a 55 gallon drum or two free. Those were great times! Avgas must perform as well at takeoff as it does at altitude so saying that Avgas is not going to be 100 octane at sea level but then is magically 100 octane at altitude is incorrect. Octane is octane.
Another wonderful thing about Avgas is that it can be stored for up to 12 months with very little degradation. The bad thing about Avgas is that road taxes are not paid on it so there could be serious legal problems if you were to tell the wrong guy about using it on the street.
Royce my chemist friend said nothing about the "octane" characteristics at seal level. As you mentioned that can't change. He said the fuel was "formulated" for "altitude above sea level" with specific additives to perform better "up there" than at sea level. He also mentioned it was "good for a year in the ground" unlike "highway gas". With him having a PHD in chemistry , I took his advice.
Quote from: Royce Peterson on March 27, 2020, 10:02:21 AM
Lots of bad information there Doug. Since when is it not legal to store gasoline in gas cans anywhere? It isn't.
My 428CJ seems happy enough on super unleaded. The pure gas / no ethanol kind is available everywhere here in Tulsa.
Meanwhile the 427 in my other car is not happy on anything less than a 50/50 mix of race gas and super unleaded. It really has 10.9:1 compression - it is factory stock - so I get 110 octane VP in 5 gallon cans. Typically I do not run below 1/2 tank so 3 gallons of race gas and 3 gallons of pump gas and it's happy. I drive my cars maybe 1000 miles each per year so it's not a lot of money to keep the one full of the fuel it likes.
Avgas is great stuff too but you have to run a higher percentage in order to get the same results because it is only 100 octane while VP110 is 110 octane. Back when I worked on airplanes for a living I would occasionally get a 55 gallon drum or two free. Those were great times! Avgas must perform as well at takeoff as it does at altitude so saying that Avgas is not going to be 100 octane at sea level but then is magically 100 octane at altitude is incorrect. Octane is octane.
Another wonderful thing about Avgas is that it can be stored for up to 12 months with very little degradation. The bad thing about Avgas is that road taxes are not paid on it so there could be serious legal problems if you were to tell the wrong guy about using it on the street.
Well Royce, you wouldn't be happy living here. We have these things called building and zoning codes.
You can keep up to 5 gallons in some places and in others the Fire Departments limit that to one gallon.
That's the cost of civilization. There are rules.
Let's see? So far I've stepped on your toes as far as you selling off your W code Mustangs and now racing gas?
Anything else that pisses you off? You yokels are somethin' else.
Quote from: CSX 4133 on March 26, 2020, 10:01:45 PM
Bob,
Here's one...
https://www.pure-gas.org/station?station_id=9641
pure-gas.org has a list by city if this one doesn't work. Do you know the location of the Pilot selling 110?
Steven,
Yes.... Exit 355 west on I-40 just this side of Kingston. One white pump sitting in the middle, of the middle island. A deal in my opinion at $7.50 per gallon.
BG
I don't claim to be a chemist nor do I play one on TV. I am a semi - retired former A+P / IA with 40 years experience, nearly none of it with piston engined aircraft. The 11 years while working for the largest automaker in the world I mostly maintained their fleet of corporate jets but occasionally had to work on a experimental aircraft that belonged to a retired COO of the company. It was during this period of time that we had to defuel the aircraft several times, with me being the lucky recipient of lots of free fuel. My experience is that it's fabulous stuff for free. Better than anything you can buy at the pump.
Aircraft make the most power during take off, not at altitude. Hence the various power ratings for modern aircraft engines, max takeoff power, max cruise, etc. I don't know your guy and he's not here to defend himself. I only deal in facts.
Quote from: gt350hr on March 27, 2020, 10:54:32 AM
Royce my chemist friend said nothing about the "octane" characteristics at seal level. As you mentioned that can't change. He said the fuel was "formulated" for "altitude above sea level" with specific additives to perform better "up there" than at sea level. He also mentioned it was "good for a year in the ground" unlike "highway gas". With him having a PHD in chemistry , I took his advice.
Quote from: gt350hr on March 27, 2020, 10:54:32 AM
Royce my chemist friend said nothing about the "octane" characteristics at seal level. As you mentioned that can't change. He said the fuel was "formulated" for "altitude above sea level" with specific additives to perform better "up there" than at sea level. He also mentioned it was "good for a year in the ground" unlike "highway gas". With him having a PHD in chemistry , I took his advice.
On reason aircraft piston engines make such good power on takeoff is that they have an an extra control that you don't see in an auto engine, a mixture control. On takeoff, the pilot sets the mixture to full rich. This control also allows the mixture to be set for best power at altitude. Back before the introduction of 100LL, avgas had two octane numbers such as 80/87 or 100/130. The lower number was for the lean setting and the higher number for, you guessed it, the full rich setting. IIRC, avgas is also formulated to burn well at a somewhat lower RPM than mogas. Airplane engines operate at pretty much a steady state RPM once they get to cruise altitude. Full power is generally only need during climb, whereas in a car you are constantly changing RPM in traffic and only get to a steady state condition while in cruise on the open road. So two different formulations for two different usages.
Quote from: Royce Peterson on March 27, 2020, 10:02:21 AM
Avgas is great stuff too but you have to run a higher percentage in order to get the same results because it is only 100 octane while VP110 is 110 octane.
Quote from: gt350hr on March 27, 2020, 10:54:32 AM
He said the fuel was "formulated" for "altitude above sea level" with specific additives to perform better "up there" than at sea level.
Quote from: gt350hr on March 26, 2020, 05:23:57 PM
The formulation is not "ideal" for a racing engine , no question about that.
Years ago I used to use the "green" AV gas . This was before the reformulation to "blue" Low Lead 100. When it changed I asked a friend who was a chemist for Conoco in the Santa Maria area regarding me still using it. He suggested that it should be mixed with pump gas to no more than 50% and not used above 11-1 static compression. "He" claimed that the additive package WAS altered and not "happy" at sea level in undiluted form.
I'm also not an automotive fuel chemist, but I have tried to ask questions of supposedly knowledgeable persons who's response is often: it's to complicated to explain, and if they did, then they'd have to kill me, so I'm short on facts. But I agree with the above observations and would like to add to them.
First, I have found that when running the AV gas, it requires more volume than say the race fuel, so although if running race fuel and substituting AV gas the performance may drop off, but not necessarily due to octane but rather a slight leaning effect (but then maybe your tune was to fat). One generally will find that when tuned for AV gas say for driving around on the streets, but then for race day substitutes race fuel, the tune will be to fat, perhaps to the point of fouling the plugs, which is partly the formulation intent of AV gas to avoid, as many aviation engines intentionally run over-rich scenarios for the purpose of engine cooling requirements. You can run a lot of AV gas thru the engine and still not foul a plug.
And yes, 100LL is formulated with intent at altitude, and this may be witnessed as it demonstrates a faster flash rate than particularly the race fuels, perhaps one of the concerns when operating at street level particularly in hot environments, just make sure there's an electric pump at the rear to push the fuel forward. This general is also realized as better cold starting of ones' performance engine, particularly those demonstrating poor cold start and low speed driveability, as the readily fuel flashes within the coldest and least turbulent of induction systems. And again, the plugs last a lot longer in the street driving scenario.
Also the 100LL is not an equivalent measurement number as compared to street or race fuels, it is of less resultant octane value as experienced in the engine, therefore a compounding factor in the mixing volumes even in excess of perhaps a lower numerical rating as presented in the example of the 100LL vs. Sonoco 110. In my attempts to discern through experimentation, I'd guess it to be of something greater than typical street fuel to perhaps maybe say 96 octane. One reason for some experiencing a greater value I believe is due to an effect of mixing fuels, this creating a new chemistry, every varying, depending on the mix, and all of this why the knowledgeable persons' statement of limiting this to engine of say 11:1 +/-. And the particular quirks of one engine design versus others and its' relationship to the fuel also muddies the conclusions. For example: in my Lycoming 260HP 540, with the MA6 helicopter carburetor (no altitude compensation function & a tune for higher load, hence richer fueling), timing advanced from the factory specification of 25° to 28°, it performs significantly better but detonates on 100LL. I have found in this application that a 60-30 mix of the 89 octane ethanol free ("RV" fuel) & 110 race fuel works best. But that's only for this instance. ;)
Well, that's my effort of adding fuel to this fire! ::)
Scott.
QuoteOn reason aircraft piston engines make such good power on takeoff is that they have an an extra control that you don't see in an auto engine, a mixture control.
Unless you go back to the Model A Ford...It's called the GAV valve... ;)
TOB
Quote from: S7MS427 on March 27, 2020, 09:01:58 PM
On reason aircraft piston engines make such good power on takeoff is that they have an an extra control that you don't see in an auto engine, a mixture control. On takeoff, the pilot sets the mixture to full rich. This control also allows the mixture to be set for best power at altitude.
Just a note: as I mentioned previously, the air-cooled aircraft engine designs often utilize an over-rich fueling condition for the purpose of an additional engine cooling function, and this being beyond best jetting for performance is generally the result of the "Full-Rich" mixture control setting; but this is required for some of these air-cooled engines as otherwise they may suffer a cylinder over heat and detonation scenario under their maximum usable power routine of takeoff and maximum climb particularly if of tropic air temperatures and at higher air pressures of sea level thru low altitude are included. :)
This is not so unlike the current tuning exploits of over-rich values being executed today, particularly on the street vehicles with forced induction sums beyond that which the intended to run 93 octane pump gas will support. This is often with the misunderstanding that even so, when the engine still experiences a detonation failure, the statement often made is that it apparently must have gone "lean", when in fact, it may have actually only been leaner to the point of better, or shall we say closer to "ideal" for best power, to bad the fuel wasn't more capable! :o
Scott.
Quote from: S7MS427 on March 27, 2020, 09:01:58 PM
Quote from: gt350hr on March 27, 2020, 10:54:32 AM
Royce my chemist friend said nothing about the "octane" characteristics at seal level. As you mentioned that can't change. He said the fuel was "formulated" for "altitude above sea level" with specific additives to perform better "up there" than at sea level. He also mentioned it was "good for a year in the ground" unlike "highway gas". With him having a PHD in chemistry , I took his advice.
On reason aircraft piston engines make such good power on takeoff is that they have an an extra control that you don't see in an auto engine, a mixture control. On takeoff, the pilot sets the mixture to full rich. This control also allows the mixture to be set for best power at altitude. Back before the introduction of 100LL, avgas had two octane numbers such as 80/87 or 100/130. The lower number was for the lean setting and the higher number for, you guessed it, the full rich setting. IIRC, avgas is also formulated to burn well at a somewhat lower RPM than mogas. Airplane engines operate at pretty much a steady state RPM once they get to cruise altitude. Full power is generally only need during climb, whereas in a car you are constantly changing RPM in traffic and only get to a steady state condition while in cruise on the open road. So two different formulations for two different usages.
Thanks for presenting "the facts" Roy. I'm not a pilot but I did know about going full rich for take off. I started using AV gas 50 years ago and never found an issue "specific" to it's use except "some" lead spotting on the plug with pre 100LL formulation ( green colored gas). I ran that stuff straight with 11.5 CR.
Randy
Many puddle jumper sized civilian aircraft still have mixture and carburetor heat controls because the aircraft are 40 or more years old. There is a basic physics reason for a richer mixture at sea level than you would use at say Denver Stapleton. There is less air in the atmosphere as altitude increases. Aircraft engines are tuned for best power at takeoff, full rich. As the aircraft climbs there is less oxygen in the air, so the fuel mixture must be decreased to maintain a stoichiometric ratio that is acceptable for that altitude. Modern aircraft piston engines use electronic fuel injection to maintain the most efficient mixture. Many aircraft have turbosuperchargers to offset the effects of altitude.
All of this leads to confusion of folks who work on cars, or who like to comment on the subject even though they themselves don't.
Quote from: gt350hr on March 30, 2020, 01:00:19 PM
Quote from: S7MS427 on March 27, 2020, 09:01:58 PM
Quote from: gt350hr on March 27, 2020, 10:54:32 AM
Royce my chemist friend said nothing about the "octane" characteristics at seal level. As you mentioned that can't change. He said the fuel was "formulated" for "altitude above sea level" with specific additives to perform better "up there" than at sea level. He also mentioned it was "good for a year in the ground" unlike "highway gas". With him having a PHD in chemistry , I took his advice.
On reason aircraft piston engines make such good power on takeoff is that they have an an extra control that you don't see in an auto engine, a mixture control. On takeoff, the pilot sets the mixture to full rich. This control also allows the mixture to be set for best power at altitude. Back before the introduction of 100LL, avgas had two octane numbers such as 80/87 or 100/130. The lower number was for the lean setting and the higher number for, you guessed it, the full rich setting. IIRC, avgas is also formulated to burn well at a somewhat lower RPM than mogas. Airplane engines operate at pretty much a steady state RPM once they get to cruise altitude. Full power is generally only need during climb, whereas in a car you are constantly changing RPM in traffic and only get to a steady state condition while in cruise on the open road. So two different formulations for two different usages.
Thanks for presenting "the facts" Roy. I'm not a pilot but I did know about going full rich for take off. I started using AV gas 50 years ago and never found an issue "specific" to it's use except "some" lead spotting on the plug with pre 100LL formulation ( green colored gas). I ran that stuff straight with 11.5 CR.
Randy
My apologies to all when I added fuel to the fire regarding AV gas.
Sunoco 110 is very high quality racing gas. I use it in my Drag Race only '66 GT350 . Running my GT350 at the Mid America meet is on my bucket list.
Randy