Author Topic: Gas Mileage: 454  (Read 102889 times)

Offline BrandonMc

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  • Year: 1988
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  • Model: Chieftain
  • Chassis: P30
  • Engine: 454
Re: Gas Mileage: 454
« Reply #150 on: August 09, 2018, 10:36 AM »
I have to say I've enjoyed reading this thread, and can't wait to reveal my MPG when the fuel system is back together.


Something not many of you have mentioned is what Octane rating are you all running? In Colorado, we have 85-87-89 available at most pumps. Now check this out, the label of a lot of P30 Chevys strictly say, FUEL REQUIREMENTS - USE 89 OCTANE OR HIGHER" This from the P30 Chassis manual page 7-92. My 89 454, and many others I'd assume says to run 89 octane!


What say you? I've always put 85 in to save a few bucks but this could be relatively important right? I suppose it depends on your locale. 



Offline tmsnyder

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Re: Gas Mileage: 454
« Reply #151 on: August 09, 2018, 11:32 AM »
The cheapest stuff available!  Yes I ran a bunch of 85 octane last summer on our 8000 mile loop out west and back.

Offline 87Itasca

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Re: Gas Mileage: 454
« Reply #152 on: August 09, 2018, 12:47 PM »
You mean 87 Octane?


There's no way I would run E85 in one of these. I couldn't imagine it would run at all well, and if it somehow did, you would ruin the fuel system in short order. These were not designed for ethanol fuels. 10% ethanol is pushing it already, any more and you're just asking for trouble.

Offline tmsnyder

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Re: Gas Mileage: 454
« Reply #153 on: August 09, 2018, 01:37 PM »
Oh yeah, 85 octane all day long.  Cheapest stuff they had.  Makes no difference in MPG, only problem would be preignition and I never heard any of that.  These are low compression engines, it doesn't need high octane. 


I do worry about the ethanol attacking fuel system components, so when I get home I arrive as empty as possible and fill up with ethanol-free, drive it around a bit, run the generator, and park it. 


Ethanol actually _increases_ the octane of gasoline, it's 113 octane on its own.   So if they are selling 85 octane with 10% ethanol, it would actually be lower without the ethanol, about 83 octane.

Offline BrandonMc

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Re: Gas Mileage: 454
« Reply #154 on: August 13, 2018, 09:55 AM »

You mean 87 Octane?


There's no way I would run E85 in one of these. I couldn't imagine it would run at all well, and if it somehow did, you would ruin the fuel system in short order. These were not designed for ethanol fuels. 10% ethanol is pushing it already, any more and you're just asking for trouble.


Definitely like to avoid ethanol based fuels. What you're saying is Ethanol is being used to affect the octane rating of gasoline?  oh wait, I see. No, definitely not running E85 AT ALL!



Oh yeah, 85 octane all day long.  Cheapest stuff they had.  Makes no difference in MPG, only problem would be preignition and I never heard any of that.  These are low compression engines, it doesn't need high octane. 


That's what I thought!  Hm?  Why do you think the label specifically says run 89 or higher?

Offline fasteddie313

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Re: Gas Mileage: 454
« Reply #155 on: August 14, 2018, 01:20 PM »
I'm no 454 expert, but..


You should get better gas mileage and more power with the lower octane gas..


In gasoline the octane is artificially increased with additives..
The additives serve to slow down the burn of the fuel and increase it's resistance to ignition..
Higher octane gas is harder to ignite and burns slower.. This is needed for high compression engines and forced induction engines.


Ethanol burns even slower, has a much lower energy density, and is much more resistant to ignition..


Ethanol burns so much slower that flex fuel applications run a lot more ignition advance with high ethanol content to get peak cylinder pressure back near TDC.. You have to fire the sparkplug earlier to get it burning right before the piston gets to the top vs straight gasoline..


Ethanol contains much less energy..
""
A.  76,000  = BTU of energy in a gallon of ethanol[/size]B.  116,090 = BTU of energy in a gallon of gasoline
""
""
[/size]Ethanol[/size]
[/size] and fuels like E85. 1.5 gallons of [/color][/size]ethanol[/color][/size] has the same [/color][/size]energy[/color][/size] content as 1.0 gallon of [/color][/size]gasoline[/color][/size]. A flex-fuel vehicle will experience about 76% of the fuel mileage MPG when using E85 (85% [/color][/size]ethanol[/color][/size]) products as compared to 100%[/color][/size]gasoline[/color][/size].[/color][/size]""[/color]
So all else equal you will get worse MPG on ethanol than gas because of the energy content difference..


Ethanol requires a different Air Fuel Ratio for a proper burn compared to gasoline..



As you can see gasoline has a stoichiometric ratio of 14.7 parts air to 1 part gasoline while ethanol's stoichiometric ratio is 9.8 parts air to 1 part E85..


So you need more ethanol for the same amount of air to get a proper fire than you do with gasoline..


Flex fuel engines have a computer that sees the ethanol content of the fuel, via a flex fuel sensor, and sees the AFR of the burnt exhaust, via O2 sensors, so the computer can add more fuel at the same amount of airflow to get back to stoichiometric with changing fuels..


Carburetors don't do that, they are tuned for a specific fuel type..
If you run ethanol in a carb tuned for gasoline then you will be mixing the same amount of fuel when you should be adding more and you will be lean..


You can tune a carb for ethanol though, but then it will be pig rich on gasoline.


Back to octane, octane is the measure of resistance to ignition.. It's easier to catch low octane fuel on fire basically.. E85 having an octane rating somewhere around 100-110 octane, so it is harder to catch on fire..


High performance engines at times need high octane fuel to keep it from catching on fire before the sparkplug catches it on fire on purpose..
Sometimes the fuel mixture can catch on fire in the cylinder way too early and then you have a huge explosion while the piston is still coming up, fighting it, and can cause catastrophic engine damage..
This can be from a glowing hot spark plug or just too much heat in the air when it is being compressed.. So you need higher octane to make sure it doesn't catch on fire on its own before you want it to by firing the sparkplug..




Regular gasoline displays these same features with increasing octane rating but to a lesser extent than going from gasoline to ethanol..




If you don't need high octane to keep your fuel from catching of fire before it is supposed to because you have you engine so hopped up, then you will get more power and better MPG with the lowest octane fuel your engine can handle..


the lower the octane the better unless you have a problem and need to make it harder to ignite..
Modern high compression engines and turbo/supercharged engines (which really just increase the dynamic compression ratio, FI)




So yeah, run that low octane crap in your low compression 454 for the best MPG and power..
Unless you hear it pinging/knocking, then you probably have carbon deposits on your head/piston top/valve surfaces that keeps glowing hot in between power strokes and/or increasing your compression ratio (taking up volume)..
In that case pull your heads and clean the carbon out of there, or try some magic that may or may not work like seafoam..
An engine will usually knock at peak torque RPM and lower..
You know that sound when you turn your distributor too far and it starts firing against the engine.. That's the sound to watch for..


Water injection is a darn good way of cleaning carbon too.. Steam clean..

Offline Rickf1985

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Re: Gas Mileage: 454
« Reply #156 on: August 14, 2018, 04:30 PM »
A good way to clean the carbon out of the cylinders is to force feed it water. Take the air cleaner off and get a 2 liter bottle of water. Warm the engine up to operating temp and then holding the water bottle in one hand and operating the throttle with the other, start raising the rpm and as you do start pouring the water down the carb. You will be trying to maintain the engine running at a around 1200-1500 rpm but you want to keep increasing the throttle and increasing the water as you do. This will keep the engine at the rpm mentioned. You don't want to open the secondaries but you do want to be close to full throttle on the primaries. Do this for about 15-20 seconds and taper off the water as you bring the throttle back. Then let it idle for a while to dry out the condensation that will have formed in the exhaust. Go for a ride afterwards to finish the drying. You are done. If you were to take the heads off at this point the pistons would look brand new, as would the heads. The one thing you have to be careful of is to not dump a whole bunch of water in and stall the engine. If it starts to stall stop the water. If it stalls and you keep dumping you can hydrolock the engine.

Offline TerryH

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Re: Gas Mileage: 454
« Reply #157 on: August 14, 2018, 05:37 PM »
Isn't that a form of torture? :)rotflmao :)rotflmao :)rotflmao

Offline Rickf1985

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Re: Gas Mileage: 454
« Reply #158 on: August 14, 2018, 05:54 PM »
Right from the manual. W%

Offline BrandonMc

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Re: Gas Mileage: 454
« Reply #159 on: August 15, 2018, 09:35 AM »

I'm no 454 expert, but..



learned something new today!


A good way to clean the carbon out of the cylinders is to force feed it water.


umm, wow that sounds crazy. my engine seems pretty tip top shape currently at 54,000mi

Offline Wkdemers

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Re: Gas Mileage: 454
« Reply #160 on: August 16, 2018, 12:37 AM »
https://www.livescience.com/58117-does-gasoline-go-bad.html




Google 'companies being sued for selling water contaminated gasoline'... They are messing with the gas, they know what they are doing and they are getting busted but not near enough and the media is hush-hush about it... The gas we buy today stinks! I have a 97 Expedition, a 98 Mustang V6, a F150 v6, and none of them run like they did years ago. Since that gas crash of 08 the American people have been getting scammed and robbed blind. There was one time I actually literally pumped several dollars worth of air! I didn't hear the gurgling of fuel entering my gas spout and decided to pull the nozzle out a little bit and still didn't hear anything I pulled it out some more until I knew there was nothing coming out and I pulled it all the way out and held it up in the air with the trigger pulled as I was watching the dial on the pump rack up dollars! We are being sold watered-down gasoline, gasoline 'cut' with ethanol (which draws water) who knows what other kind of fillers are being used to rip us off, we are just being ripped off. Just like in family law, CPS, got taxes for everything under the sun, cops waiting behind every corner to give you a ticket or find some fault with you or try to take your kids away inviting your wife to divorce you and rob you blind so they can get their cut. Anyways don't get me started. I wouldn't automatically suspect something wrong with your machine is what I'm saying.


Sorry about the rant guys, I know it's my first post and it's probably tacky but I've had it with three-piece-suit-wearing badge-flashing scam artists and feel it's my duty to call them out at every opportunity.


Thank you Jesus.



By the way I thought I might add this is in no way any kind of response to mr. Ricks post above, which I thought was interesting I've never tried that... If I do try it and it works, well I'll shut my mouth LOL

PS nice to meet you guys. I have a 93 Pace Arrow that I intend to do some work on and stumbled across this forum. :)
If I would have known then what I know now I wouldn't have knew what I now know! D:

Offline Wkdemers

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Re: Gas Mileage: 454
« Reply #161 on: August 16, 2018, 12:43 AM »
Oops
If I would have known then what I know now I wouldn't have knew what I now know! D:

Offline Rickf1985

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Re: Gas Mileage: 454
« Reply #162 on: August 16, 2018, 09:32 AM »
A good way to clean the carbon out of the cylinders is to force feed it water. Take the air cleaner off and get a 2 liter bottle of water. Warm the engine up to operating temp and then holding the water bottle in one hand and operating the throttle with the other, start raising the rpm and as you do start pouring the water down the carb. You will be trying to maintain the engine running at a around 1200-1500 rpm but you want to keep increasing the throttle and increasing the water as you do. This will keep the engine at the rpm mentioned. You don't want to open the secondaries but you do want to be close to full throttle on the primaries. Do this for about 15-20 seconds and taper off the water as you bring the throttle back. Then let it idle for a while to dry out the condensation that will have formed in the exhaust. Go for a ride afterwards to finish the drying. You are done. If you were to take the heads off at this point the pistons would look brand new, as would the heads. The one thing you have to be careful of is to not dump a whole bunch of water in and stall the engine. If it starts to stall stop the water. If it stalls and you keep dumping you can hydrolock the engine.


I did not intend for people to just go out and do this just to say they have a clean engine. This is something you do if you have symptoms of excess carbon in the cylinders like pinging when it shouldn't be or a cylinder with higher than normal compression.


Just running E10 gasoline will clean most of the deposits over time. Ethanol does have that one redeeming factor, it is a fantastic solvent. It is the main ingredient in all of the over the counter gas treatments so keep that in mind if you ever want to add a gas treatment to your car, you are probably already running it in the form of the gasoline.


Wkdemers, we have been getting ripped off by the gas companies since 1976. Ask Google to tell what happened then.  They own the government, not only here but in most oil producing countries so you are going to have to live with it.

 

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