110 Octane Leaded Gas in Car??

[SkyHog]

Assume I have no O2 sensors or Catalytical Converter. What is the risk of running leaded gasoline through an unleaded engine?

No environment answers....car answers only.

 

[Alexb2000]

Nothing will happen, but your car will run good. I always recommend people with classic cars they don't drive that much use avgas. No ethanol means the gas won't go bad.

 

[docmirror]

No risk. It'll run fine. You may not be getting your money's worth from the octane but it won't damage anything.

 

[warthog1984]

What's your compression? If it's a low-compression engine your mileage may suffer. If it's high-compression, better mileage and less knock.

Other than that, just getting lead scattered throughout your engine- not something I'd do by choice, since I'm the one that would be getting that junk all over me during maintenance.

 

[SkyHog]

What's your compression? If it's a low-compression engine your mileage may suffer. If it's high-compression, better mileage and less knock.

Other than that, just getting lead scattered throughout your engine- not something I'd do by choice, since I'm the one that would be getting that junk all over me during maintenance.

Its a JXR1000 engine...and the maintenance will likely be done by me as time goes on.

 

[RJM62]

If you choose to do that, I suggest not using synthetic oil (which would pretty much heresy for me in any other situation). The synthetic doesn't hold lead in suspension very well.

-Rich

 

[warthog1984]

Its a JXR1000 engine...and the maintenance will likely be done by me as time goes on.

Neither I nor Google knows what a JXR1000 engine is, or where it's from. Personally I avoid lead like the plague since I've been able to correlate health changes to fluctuations in my blood lead level (I'm a pilot, shootist, and handloader), but it's your health.

 

[SkyHog]

Neither I nor Google knows what a JXR1000 engine is, or where it's from. Personally I avoid lead like the plague since I've been able to correlate health changes to fluctuations in my blood lead level (I'm a pilot, shootist, and handloader), but it's your health.

Sorry, that would be GSXR

 

[txflyer]

I run 100LL in the mopar even though it's had a head job to harden the seats for unleaded.

Classic scene last time I was driving it. Two redneck boys pull up alongside me in a pickup, and the rider yells at me "whatcha burning in that thing?" "Is it a hemi?"

Avgas is excellent for chainsaw's, trimmers, lawn mowers, muscle cars, anything you want to run better, and you can leave it in the tanks all year long and it won't gum up. People always say "yeah, but that stuff is expensive." I reply "how much is a carb and total fuel system overhaul?"

 

[SkyHog]

Are the Cats and the O2 sensors the only difference between an engine designed for UL and one designed for Leaded fuel?

If so, that makes the answer really easy.

 

[RJM62]

The valves and valve seats typically are more hardened in an engine designed for unleaded. The leaded fuel shouldn't hurt unleaded valves.

-Rich

 

[timwinters]

I typically run a 50/50 mix of 100LL/MoGas in all of my equipment around the farm especially the stuff that's used intermittently. It all likes it. No varnish issues even when it sits for a full year...like my log splitter frequently does.

I'd be hesitant to run straight 100LL in anything that wasn't built for it though.

 

[FormerHangie]

You may possibly get lead fouling of your spark plugs, and like Rich said, don't run fully synthetic motor oil. If you ride it like most GSXR riders ride their bikes, I don't think lead fouling will be a problem.

If it's a stock GSXR, you're paying for octane that is not giving you any benefit.

 

[warthog1984]

Sorry, that would be GSXR

A gixxer is not a "car".

There are a few differences in leaded and unleaded-design engines besides the seats (plumbing mostly), but your tea-kettle is a race-derived engine and will handle lead fine.

That having been said, a stock OEM gixxer will see little benefit from super-octane gas due to the chip tuning. Before throwing expensive gas in a supersport, I'd get it dyno-tuned for the gas and application I'd expect it to see- whether that's street-only pump gas, track-only racing, or streetable track toy / canyon carver.

 

[Zeldman]

Are the Cats and the O2 sensors the only difference between an engine designed for UL and one designed for Leaded fuel?

If so, that makes the answer really easy.

Easy answer: No. You could take out the O2 sensors and remove the cats and run it. But you will have problems later on. Av gas is not friendly to electronic fuel injection as well.

Just one question, what RPM do you see in your engine? Av-gas is leaded, yes, but also designed to run in a low compression engine aircraft engine, at 3000 rpm, or less, at a steady RPM. Like an airplane engine does. My race engines never ran as low as 3000 RPM except at the start of the race. My race engines were designed for wide open throttle to closed throttle, repeat up to 1000 times per race. (2 straight aways) Something airplane engines don't do.

I raced cars for years, had a race fuel business and was a gas specialist on a team that ran a car in the Winston Cup Series. So I am sure that with my experience there will be someone here to tell me I don't know squat. Listen to that person, ruin your engine, then bring it to me and I will tell you what went wrong. The only race people that ran av gas at the race tracks were also airplane people and it was in their planes. With that said, a decent engine builder can build an engine to run on avgas, but a good engine builder won't do it. He values his reputation too much.

After asking around, I guess you could run a little av gas in the super unleaded to get a little lead in it. Say around 1 gallon avgas to 9 gallon super. It won't raise the octane number. Just make sure the super unleaded wasn't made with methanol in it because lead and methanol won't mix together. The ethanol blend doesn't seem to bother it as much. But as we all know, ethanol doesn't make the power or gas mileage that real gasoline will. I know Indy cars run ethanol but that was a political move to slow down the cars and to please corn farmers.

EDIT: Forgot to add one thing. Avgas octane rating is not the same as car gas octane rating. The avgas rating uses a performance rating. Remember when avgas was called 100/110, or something like that? Car gas octane rating uses the research method plus motor method divided by 2.

R+M equals octane rating.
2

So avgas would come out to somewhere around 80 to 85 on the R+M over 2 method.

But don't listen to me. I don't know squat.

 

[warthog1984]

Just one question, what RPM do you see in your engine? Av-gas is leaded, yes, but also designed to run in a low compression engine (compared to cars), at 3000 rpm, or less, at a steady RPM.

He's proposing to run leaded race fuel in a 1000cc supersport bike. I'm guessing the bike will see 9,000-12,000rpm regularly.

 

[Zeldman]

He's proposing to run leaded race fuel in a 1000cc supersport bike. I'm guessing the bike will see 9,000-12,000rpm regularly.

OOOPS... aviation related board, mentioned car, saw car picture... had car on the brain..

My mistake.

 

[BiffJ]

EDIT: Forgot to add one thing. Avgas octane rating is not the same as car gas octane rating. The avgas rating uses a performance rating. Remember when avgas was called 100/110, or something like that? Car gas octane rating uses the research method plus motor method divided by 2.

R+M equals octane rating.
2

So avgas would come out to somewhere around 80 to 85 on the R+M over 2 method.

Not sure if you know anything or not but this statement you made wasn't quite correct other than noting that aviation and car ratings aren't the same.
The 100/130 rating is based on lean(100) and rich (130) ratings on the fuel for aviation use. It is based first on what is basically equivalent to the Motor octane number up to 100 octane.
Your R+M over 2 note is really an anti-knock index number based on both the motor and research octane numbers added together and divided by 2.

In any case I have no problems with running avgas in racing engines or hot rod types other than its frequently a waste of the octane rating and just costs more than necessary. I do use it in infrequently used equipment due to the lack of varnish.

Side note....I worked on indy cars for quite a few years but only prior to the ethanol days. We ran methanol and it worked very well. We did have to "pickle" the engines after running by hooking up a tank of gas with a pump to run all the methanol out of the system and prevent corrosion. According to friends working on the cars now they have even more trouble with corrosion from ethanol.

Frank

 

[Henning]

Assume I have no O2 sensors or Catalytical Converter. What is the risk of running leaded gasoline through an unleaded engine?

No environment answers....car answers only.

The primary difference is the valve guide end. For unleaded engines, they have a rounded, tapered entry on the face side, for leaded engines they have a small square cut notch to the end that scrapes the lead off the stem into a little donut that lubricates the corner. Without this square land, the lead builds up on the valve stem and then jams up in the taper end guide and causes the valves to stick open.

BTW, you can cut the square land if you have to, there are tools specifically for it.

 

[Bill]

You may possibly get lead fouling of your spark plugs, and like Rich said, don't run fully synthetic motor oil. If you ride it like most GSXR riders ride their bikes, I don't think lead fouling will be a problem.

If it's a stock GSXR, you're paying for octane that is not giving you any benefit.

Concur. Running a stock GSXR on 100LL is not necessary. RTFM, the bike may be designed for plain old regular. I ran regular gas in all of the Hondas I owned (all the owners manuals stated 86 octane min) including fast, powerful (for the time) bikes like the 1100XX. Collectively 100's thousands of miles and no engine problems.

RTFM, use what it advises. Paying for higher octane than recommended on a stock motor is money out the tailpipe.

 

[Dr. O]

It is clear that some do not quite grasp what an octane rating is or what it high octane does for a high compression engine and why it burns just fine in a low compression engine. Best you do some reading.

Running leaded gas in your unleaded engines will not cause damage. It may cause a bit of plug fouling and possibly a sticky valve stem now and then (not real likely).

I use it in all the small engines here on the farm. We have various fertilizer transfer pumps, generators, chainsaws, yadda, yadda. Some only get run a few times a year - such as the fertilizer transfer pumps that will be started maybe a dozen times over a two week period in the spring and then sit idle for 50 weeks. With alcohol polluted gas in the tank the ones that only start in season would be a nightmare to maintain. With avgas it is blow the dust and cobwebs off the gas cap, peek in the tank to see if there is enough gas, pull the cord a couple of times, and go to work.
My PowerTow airplane tug has run avgas for the 14 years I have had it. I only remember one fouled plug in all that time.

ymmv, sar, bni

 

[poadeleted20]

There are also issues of getting caught using fuel for which the road taxes have not been paid in a vehicle on public roads. If used only off-road, it's not an issue -- many racers buy avgas to use in their race cars on the track only. And I thank them for contributing to the airport/airway development fund by doing so without making use of the facilities for which they are helping pay.

 

[SkyHog]

A gixxer is not a "car".

In this case it is....

 

[SkyHog]

Easy answer: No. You could take out the O2 sensors and remove the cats and run it. But you will have problems later on. Av gas is not friendly to electronic fuel injection as well.

Just one question, what RPM do you see in your engine? Av-gas is leaded, yes, but also designed to run in a low compression engine aircraft engine, at 3000 rpm, or less, at a steady RPM. Like an airplane engine does. My race engines never ran as low as 3000 RPM except at the start of the race. My race engines were designed for wide open throttle to closed throttle, repeat up to 1000 times per race. (2 straight aways) Something airplane engines don't do.

I raced cars for years, had a race fuel business and was a gas specialist on a team that ran a car in the Winston Cup Series. So I am sure that with my experience there will be someone here to tell me I don't know squat. Listen to that person, ruin your engine, then bring it to me and I will tell you what went wrong. The only race people that ran av gas at the race tracks were also airplane people and it was in their planes. With that said, a decent engine builder can build an engine to run on avgas, but a good engine builder won't do it. He values his reputation too much.

After asking around, I guess you could run a little av gas in the super unleaded to get a little lead in it. Say around 1 gallon avgas to 9 gallon super. It won't raise the octane number. Just make sure the super unleaded wasn't made with methanol in it because lead and methanol won't mix together. The ethanol blend doesn't seem to bother it as much. But as we all know, ethanol doesn't make the power or gas mileage that real gasoline will. I know Indy cars run ethanol but that was a political move to slow down the cars and to please corn farmers.

EDIT: Forgot to add one thing. Avgas octane rating is not the same as car gas octane rating. The avgas rating uses a performance rating. Remember when avgas was called 100/110, or something like that? Car gas octane rating uses the research method plus motor method divided by 2.

R+M equals octane rating.
2

So avgas would come out to somewhere around 80 to 85 on the R+M over 2 method.

But don't listen to me. I don't know squat.

I'm actually not talking about 100LL, I am talking about 110 octane leaded track fuel. This is a really helpful post tho, I plan to keep it and reference it as I go.

 

[SkyHog]

There are also issues of getting caught using fuel for which the road taxes have not been paid in a vehicle on public roads. If used only off-road, it's not an issue -- many racers buy avgas to use in their race cars on the track only. And I thank them for contributing to the airport/airway development fund by doing so without making use of the facilities for which they are helping pay.

This would be used only off road (it isn't a street legal car anyway).

I think one reason racers buy 100LL is that the track is usually not from the local airport, and the fuel is a lot cheaper than track fuel.

 

[Alexb2000]

There are also issues of getting caught using fuel for which the road taxes have not been paid in a vehicle on public roads. If used only off-road, it's not an issue -- many racers buy avgas to use in their race cars on the track only. And I thank them for contributing to the airport/airway development fund by doing so without making use of the facilities for which they are helping pay.

There is an alternative fuel tax license and reporting structure in most states. It allows for an energy based conversion to unleaded fuel and is taxed for road use based on that. That said I've never heard of anyone even being questioned about the fuel they have in their car. We're talking about less than a drop in the ocean here.

 

[CTLSi]

The extra cost alone should discourage you from doing it. Better to run low octane, cheaper unleaded than higher than premium, super high octane 100LL in your car.

 

[Bill]

This would be used only off road (it isn't a street legal car anyway).

Oh, I don't remember what they're called, but I know the car you're talking about. Have fun racin'.

 

[Sac Arrow]

This topic comes up a lot in the sportbike forums. Not leaded gas so much but high octane race gas.

GSXR 600 engines require a minimum of 87 octane, and 1000/750 engines require a minimum of 90. Most pump gas at least out here is 87, 91 and a blended grade for 89 octane. I've always ran 89 in my 750. I've run 87 in it before with no problems. I've never personally known anyone to blow up a stock gsxr engine running 87 octane.

No amount of tuning will vary the minimum required octane. In order to beneficially use higher than the minimum required octane, you have to have mods to increase the compression and/or advance the timing. Lead notwithstanding, any higher than the minimum octane will cause you to lose power, and increase deposition. One or two points won't make a difference but race fuel in a stock engine will. Drag racers with modded Busas and ZX 14's often run 87 octane just for the additional power in fact.

Personally, I'd stick with pump unleaded gas. If you have a modded GSXR engine with raised compression, just run pump premium and if it doesn't knock it's good enough. Knocking is at it's worst under heavy load, high throttle, low RPM applications. If you're tracking the bike you'll be sitting at high RPM's most of the time anyway.

 

[Zeldman]

I'm actually not talking about 100LL, I am talking about 110 octane leaded track fuel. This is a really helpful post tho, I plan to keep it and reference it as I go.

I realized that later and apologies for my lack of reading comprehension.

 

[Henning]

This would be used only off road (it isn't a street legal car anyway).

I think one reason racers buy 100LL is that the track is usually not from the local airport, and the fuel is a lot cheaper than track fuel.

You're gonna do one of those 1100cc dirt track cars huh? What are you looking to do to modify the engine that makes you need 110 octane racing fuel? The best performance you will get is with the lowest octane fuel you can get away with. Unless you are milling the heads down or otherwise increasing compression and ICP pressures, I don't think you'll need anything more than 92 octane pump gas to deal with it. I don't know what engine mods that class allows.

 

[Capt.Crash'n'Burn]

Personally I avoid lead like the plague since I've been able to correlate health changes to fluctuations in my blood lead level (I'm a pilot, shootist, and handloader),

When it comes to handloading, the #1, hands down source of lead contamination is coming from your case tumbler, especially if you're shooting lead bullets.

Tumble your cases outside and wear a dust mask when you handle it.

 

[FormerHangie]

In this case it is....

I would consult your fuel supplier as to what the optimum fuel for your application is. If you were to ask VP, they'd probably recommend U4.4 which is lower octane but is oxygenated.

You can send them an email, I'm sure they'd be happy to suggest a fuel. My guess is that it isn't as high of octane as the one you're looking at.

 

[Capt.Crash'n'Burn]

The primary difference is the valve guide end. For unleaded engines, they have a rounded, tapered entry on the face side, for leaded engines they have a small square cut notch to the end that scrapes the lead off the stem into a little donut that lubricates the corner. Without this square land, the lead builds up on the valve stem and then jams up in the taper end guide and causes the valves to stick open.

BTW, you can cut the square land if you have to, there are tools specifically for it.

Having worked for a couple of racing head manufacturers, who made heads for leaded racing gas and other fuels, I've got to say I've never heard of this and I'll leave it at that.

 

[timwinters]

Nick,

If you're still in Colorado Springs you might also consider:

PHILLIPS 66
91 octane ethanol free
Chief Petroleum [719-473-7760]
301 S 10th St.

 

[timwinters]

Having worked for a couple of racing head manufacturers, who made heads for leaded racing gas and other fuels, I've got to say I've never heard of this and I'll leave it at that.

Just wondering, is that the diplomatic way of asking:

????

 

[SkyHog]

You're gonna do one of those 1100cc dirt track cars huh? What are you looking to do to modify the engine that makes you need 110 octane racing fuel? The best performance you will get is with the lowest octane fuel you can get away with. Unless you are milling the heads down or otherwise increasing compression and ICP pressures, I don't think you'll need anything more than 92 octane pump gas to deal with it. I don't know what engine mods that class allows.

Is that true? For some reason, I'd always heard that higher octane was better for power and speed, but if its lower, that's an easy solution

And it is a 1000cc class (1250cc if its air-cooled), the cars run motorcycle engines on both dirt and pavement, although I'm more looking at the dirt track racing. Once I buy the car (this week), I'll post more details.

 

[Sac Arrow]

Is that true? For some reason, I'd always heard that higher octane was better for power and speed, but if its lower, that's an easy solution

And it is a 1000cc class (1250cc if its air-cooled), the cars run motorcycle engines on both dirt and pavement, although I'm more looking at the dirt track racing. Once I buy the car (this week), I'll post more details.

That is true.

 

[warthog1984]

Is that true? For some reason, I'd always heard that higher octane was better for power and speed, but if its lower, that's an easy solution

Yes and no. Generally, there is less total energy in higher-octane gas, but better knock resistance. Since you get more use out of the available energy by increasing compression and optimizing timing, the best power/speed is obtained with the lowest octane fuel that does not cause knocking in your engine. So you can get better power with higher-octane fuel, IF your engine is setup to take advantage of it. Otherwise, it's just throwing $ out the tailpipe.

 

[FormerHangie]

If you're just getting started in racing, anything that makes the engine run reliably is good enough. Save the expensive gas for when you're more experience, and thus faster.