Gas/petrol

7173Mustangs.com

Help Support 7173Mustangs.com:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Joined
Jun 10, 2016
Messages
1,389
Reaction score
4
Location
England
My Car
1971 Mustang Grande
These Mustangs were made when leaded gas/petrol was the only option. Now the only option is unleaded gas/petrol.

As i understand it the two differant fuels burn at a differant tempreatures.

I am running a 351C 2V

So i need to know whether its safe to use unleaded fuel?

Do i need to use a additive?

Does anything need to be done to the engine?

Is it just a matter of altering the timing to accomodate unleaded fuel?

What octane should i be using?

Thank You ::thumb::

 
There were a couple gas vendors back in the 60's (Amoco was a biggie) who sold lead-free and many, many folks used it for their cars exclusively. The talk back then was it wasn't a big deal until you got a couple hundred K on the engine and then you had to rebuild it since the valves would be shot. Which is pretty funny since you were lucky to get 100K on any engine back then.

Biggest concern these days is the ethenol that is added.

 
These Mustangs were made when leaded gas/petrol was the only option. Now the only option is unleaded gas/petrol.

As i understand it the two differant fuels burn at a differant tempreatures.

I am running a 351C 2V

So i need to know whether its safe to use unleaded fuel?

Do i need to use a additive?

Does anything need to be done to the engine?

Is it just a matter of altering the timing to accomodate unleaded fuel?

What octane should i be using?

Thank You ::thumb::
Steve,

Hardened exhaust seat for sure and GOOD quality valves, your choice there. You won't need an additive, but if you have to use ethanol laced fuel, I would use a product that offsets the damage it can cause. I use CRC's "Phase Guard 4" if and when I am forced to use BS fuel. It stabilizes and protects against corrosion and all the other nasty things ethanol does to older cars. You may not be able to find that exact product in the UK, but that gives you an idea. I also changed ALL my rubber fuel lines to new high pressure injector hose as it IS ethanol safe. Also check your fuel pump and carb for compatibility. ( I hate ethanol!!!) If the UK still has a fuel brand WITHOUT Ethanol, then use that exclusively.

As for what octane to use, the highest you can afford as long as there is no knocking. If I remember, UK octane ratings are higher anyway. What I don't know is if the effect of that rating is the same. i.e. Does UK's 91 regular equal our 87 regular fuel. (cheapest). You may just have to try different octanes and see what runs best.

Timing and carb settings are a subject for someone else more knowledgeable.

Good luck with it,

Geoff.

 
Last edited by a moderator:
These Mustangs were made when leaded gas/petrol was the only option. Now the only option is unleaded gas/petrol.

As i understand it the two differant fuels burn at a differant tempreatures.

I am running a 351C 2V

So i need to know whether its safe to use unleaded fuel?

Do i need to use a additive?

Does anything need to be done to the engine?

Is it just a matter of altering the timing to accomodate unleaded fuel?

What octane should i be using?

Thank You ::thumb::
Steve,

Hardened exhaust seat for sure and GOOD quality valves, your choice there. You won't need an additive, but if you have to use ethanol laced fuel, I would use a product that offsets the damage it can cause. I use CRC's "Phase Guard 4" if and when I am forced to use BS fuel. It stabilizes and protects against corrosion and all the other nasty things ethanol does to older cars. You may not be able to find that exact product in the UK, but that gives you an idea. I also changed ALL my rubber fuel lines to new high pressure injector hose as it IS ethanol safe. Also check your fuel pump and carb for compatibility. ( I hate ethanol!!!) If the UK still has a fuel brand WITHOUT Ethanol, then use that exclusively.

As for what octane to use, the highest you can afford as long as there is no knocking. If I remember, UK octane ratings are higher anyway. What I don't know is if the effect of that rating is the same. i.e. Does UK's 91 regular equal our 87 regular fuel. (cheapest). You may just have to try different octanes and see what runs best.

Timing and carb settings are a subject for someone else more knowledgeable.

Good luck with it,

Geoff.
Thanks Geoff. I was planning to pull the engine as some point in the winter and get it looked at to make sure everything is as it should be. Will do what you said when its stripped down.

Will check on ethanol free fuel in the U.K. We don't have "Phase Guard 4" here in the U.K but we do have this which i am assuming is what i need?

http://www.ebay.co.uk/itm/Millers-Oils-EPS-Unleaded-Fuel-Treatment-Providing-Ethanol-Protection-250ml-/301702510185?hash=item463edef669:g:S3sAAOSw~gRVvdIX

 
I just looked in the showroom brochure for the 72 mustang and they state on page 7. "Maybe one of the four V-8's suits you; the 302 CID 2V, 351 CID 2V, 351 CID 4V and 351 CID 4V HO all run on regular gas".

If I remember correct in the 73 brochure it states 91 octane fuel was recommended.

I also agree with Bill on the no lead issue. I have a 1956 Ford Club Sedan with 292 V-8 4V 3 speed with overdrive. It never had anything but Amoco white gas, unleaded, in over 90,000 miles of driving with no issues at all with the engine. It was a one owner car.

I know some of the drag racers here with turbos prefer the E-85 fuel but you cannot get easily anymore.

If you do some checking one way to prevent spark knock for too high of compression is to add an alcohol / water injector. They did this during WWII on planes to raise the octane of the fuel. Kits are available today if you search the net.

For what few miles you will be driving you will never see the benefit of hard seats. They also add another failure point to your engine or should I say 32 points. Cutting the pocket for the seat if they do not leave a good radius in the corner can cause cracks. If they do not properly shrink fit the seats in place they can come out during operation. The old flathead Ford V-8 had Stellite valve seats and many had cracks around the valves. Racers would pull the seats out and go to a bigger valve with no seat insert.

NASCAR uses Sunoco Green, dyed green, E15 98 octane fuel that has 15% ethanol. I am not up on what compression they run now but a few years ago it was 15:1.

At our local Sunoco they sell at the pump I think up to 100 octane with no ethanol for the local racers.

I worked in the lawn equipment business for many years. We tested all types of fuel and if you used a high octane fuel in the air cooled engines it raises the operating temperatures and cause premature failure as compared to low octane fuel. Straight alcohol runs the coolest but the engine also drinks it. Some drag racers here that run on alcohol do not even have a radiator the alcohol runs so cool. On the small engines it took about twice the amount of alcohol to get the same power as with gasoline and you had to restrict the air cooling to get the engine to correct operating temp.

So do a little testing on your engine when it is going and run the lowest octane you can and not get spark knock to reduce heat. I would not do the valve seats myself.

 
I just looked in the showroom brochure for the 72 mustang and they state on page 7. "Maybe one of the four V-8's suits you; the 302 CID 2V, 351 CID 2V, 351 CID 4V and 351 CID 4V HO all run on regular gas".

If I remember correct in the 73 brochure it states 91 octane fuel was recommended.

I also agree with Bill on the no lead issue. I have a 1956 Ford Club Sedan with 292 V-8 4V 3 speed with overdrive. It never had anything but Amoco white gas, unleaded, in over 90,000 miles of driving with no issues at all with the engine. It was a one owner car.

I know some of the drag racers here with turbos prefer the E-85 fuel but you cannot get easily anymore.

If you do some checking one way to prevent spark knock for too high of compression is to add an alcohol / water injector. They did this during WWII on planes to raise the octane of the fuel. Kits are available today if you search the net.

For what few miles you will be driving you will never see the benefit of hard seats. They also add another failure point to your engine or should I say 32 points. Cutting the pocket for the seat if they do not leave a good radius in the corner can cause cracks. If they do not properly shrink fit the seats in place they can come out during operation. The old flathead Ford V-8 had Stellite valve seats and many had cracks around the valves. Racers would pull the seats out and go to a bigger valve with no seat insert.

NASCAR uses Sunoco Green, dyed green, E15 98 octane fuel that has 15% ethanol. I am not up on what compression they run now but a few years ago it was 15:1.

At our local Sunoco they sell at the pump I think up to 100 octane with no ethanol for the local racers.

I worked in the lawn equipment business for many years. We tested all types of fuel and if you used a high octane fuel in the air cooled engines it raises the operating temperatures and cause premature failure as compared to low octane fuel. Straight alcohol runs the coolest but the engine also drinks it. Some drag racers here that run on alcohol do not even have a radiator the alcohol runs so cool. On the small engines it took about twice the amount of alcohol to get the same power as with gasoline and you had to restrict the air cooling to get the engine to correct operating temp.

So do a little testing on your engine when it is going and run the lowest octane you can and not get spark knock to reduce heat. I would not do the valve seats myself.
What I find most interesting about your post is the experiments you did with small air cooled engines. I have used 91 in them knowing it might be unnessary but not thinking about how they might run hotter on the higher octane. I have also used a ethanol free gas in a can that is expensive but the amount I use makes it no big deal. This is also at least 91 octane and I thought I was better off without the ethanol in the small motors. Now I am wondering....(sorry for the hijack)

 
I just looked in the showroom brochure for the 72 mustang and they state on page 7. "Maybe one of the four V-8's suits you; the 302 CID 2V, 351 CID 2V, 351 CID 4V and 351 CID 4V HO all run on regular gas".

If I remember correct in the 73 brochure it states 91 octane fuel was recommended.

I also agree with Bill on the no lead issue. I have a 1956 Ford Club Sedan with 292 V-8 4V 3 speed with overdrive. It never had anything but Amoco white gas, unleaded, in over 90,000 miles of driving with no issues at all with the engine. It was a one owner car.

I know some of the drag racers here with turbos prefer the E-85 fuel but you cannot get easily anymore.

If you do some checking one way to prevent spark knock for too high of compression is to add an alcohol / water injector. They did this during WWII on planes to raise the octane of the fuel. Kits are available today if you search the net.

For what few miles you will be driving you will never see the benefit of hard seats. They also add another failure point to your engine or should I say 32 points. Cutting the pocket for the seat if they do not leave a good radius in the corner can cause cracks. If they do not properly shrink fit the seats in place they can come out during operation. The old flathead Ford V-8 had Stellite valve seats and many had cracks around the valves. Racers would pull the seats out and go to a bigger valve with no seat insert.

NASCAR uses Sunoco Green, dyed green, E15 98 octane fuel that has 15% ethanol. I am not up on what compression they run now but a few years ago it was 15:1.

At our local Sunoco they sell at the pump I think up to 100 octane with no ethanol for the local racers.

I worked in the lawn equipment business for many years. We tested all types of fuel and if you used a high octane fuel in the air cooled engines it raises the operating temperatures and cause premature failure as compared to low octane fuel. Straight alcohol runs the coolest but the engine also drinks it. Some drag racers here that run on alcohol do not even have a radiator the alcohol runs so cool. On the small engines it took about twice the amount of alcohol to get the same power as with gasoline and you had to restrict the air cooling to get the engine to correct operating temp.

So do a little testing on your engine when it is going and run the lowest octane you can and not get spark knock to reduce heat. I would not do the valve seats myself.
What I find most interesting about your post is the experiments you did with small air cooled engines. I have used 91 in them knowing it might be unnessary but not thinking about how they might run hotter on the higher octane. I have also used a ethanol free gas in a can that is expensive but the amount I use makes it no big deal. This is also at least 91 octane and I thought I was better off without the ethanol in the small motors. Now I am wondering....(sorry for the hijack)
The plant I worked in made over 5,000 riding mowers a day, 1,000 garden tillers a day and 20,000 walk behind mowers a day. Was American Yard Products now Husqvarna. So we did lots of durability testing. We had a model shop that had a room where there were dozens of engine tests going on. They do do cold, heat even had dyno to apply load. I use the dyno for our go cart racing engines, lol.

A typical 5 hp. briggs and stratton engine like was on tillers then would only pull 3.5 hp on the dyno. My racing cart engines that had to be tech inspected to box stock would put out 7 hp. +. The model shop supervisor was amazed at double the hp using the same parts just blueprint the engine. We could not get accurate hp on racing engine the dyno had a program in the computer to hold the engines at 4,000 rpm or below. When racing I have seen the memory tach go to 7,000 with gear wrong. Usually wanted 6,000 and we used alcohol. Never blew up an engine in 6 years of racing but it was torn down after every race and new rod after every three races.

Another thing proven in the testing. Always run you mower or any small engine at full throttle it will last longer. They have a governor to prevent over revs and they do not oil properly with low rpm.

There are differences in brands using the same hp engines. John Deere requires Briggs to harden the cranks in their better models.

Always run the octane they recommend and it will last longer high octane is not better in car or mower produces unwanted heat.

 
Steve,

Hardened exhaust seat for sure and GOOD quality valves, your choice there. You won't need an additive, but if you have to use ethanol laced fuel, I would use a product that offsets the damage it can cause. I use CRC's "Phase Guard 4" if and when I am forced to use BS fuel. It stabilizes and protects against corrosion and all the other nasty things ethanol does to older cars. You may not be able to find that exact product in the UK, but that gives you an idea. I also changed ALL my rubber fuel lines to new high pressure injector hose as it IS ethanol safe. Also check your fuel pump and carb for compatibility. ( I hate ethanol!!!) If the UK still has a fuel brand WITHOUT Ethanol, then use that exclusively.

As for what octane to use, the highest you can afford as long as there is no knocking. If I remember, UK octane ratings are higher anyway. What I don't know is if the effect of that rating is the same. i.e. Does UK's 91 regular equal our 87 regular fuel. (cheapest). You may just have to try different octanes and see what runs best.

Timing and carb settings are a subject for someone else more knowledgeable.

Good luck with it,

Geoff.

Thanks Geoff. I was planning to pull the engine as some point in the winter and get it looked at to make sure everything is as it should be. Will do what you said when its stripped down.

Will check on ethanol free fuel in the U.K. We don't have "Phase Guard 4" here in the U.K but we do have this which i am assuming is what i need?

http://www.ebay.co.uk/itm/Millers-Oils-EPS-Unleaded-Fuel-Treatment-Providing-Ethanol-Protection-250ml-/301702510185?hash=item463edef669:g:S3sAAOSw~gRVvdIX

That'll work, does the same thing by the look of it. I'm sure you'll be able to buy it at a store somewhere and save the exorbitant shipping costs that get piled on to e-Bay stuff.

The other alternative of course is to replace everything from tank to carb with ethanol corrosion proof materials. The use of Ethanol is nothing short of a con job, but let's not go there right now!!

Geoff.

 
Last edited by a moderator:
Steve,

Hardened exhaust seat for sure and GOOD quality valves, your choice there. You won't need an additive, but if you have to use ethanol laced fuel, I would use a product that offsets the damage it can cause. I use CRC's "Phase Guard 4" if and when I am forced to use BS fuel. It stabilizes and protects against corrosion and all the other nasty things ethanol does to older cars. You may not be able to find that exact product in the UK, but that gives you an idea. I also changed ALL my rubber fuel lines to new high pressure injector hose as it IS ethanol safe. Also check your fuel pump and carb for compatibility. ( I hate ethanol!!!) If the UK still has a fuel brand WITHOUT Ethanol, then use that exclusively.

As for what octane to use, the highest you can afford as long as there is no knocking. If I remember, UK octane ratings are higher anyway. What I don't know is if the effect of that rating is the same. i.e. Does UK's 91 regular equal our 87 regular fuel. (cheapest). You may just have to try different octanes and see what runs best.

Timing and carb settings are a subject for someone else more knowledgeable.

Good luck with it,

Geoff.
Thanks Geoff. I was planning to pull the engine as some point in the winter and get it looked at to make sure everything is as it should be. Will do what you said when its stripped down.

Will check on ethanol free fuel in the U.K. We don't have "Phase Guard 4" here in the U.K but we do have this which i am assuming is what i need?

http://www.ebay.co.uk/itm/Millers-Oils-EPS-Unleaded-Fuel-Treatment-Providing-Ethanol-Protection-250ml-/301702510185?hash=item463edef669:g:S3sAAOSw~gRVvdIX

That'll work, does the same thing by the look of it. I'm sure you'll be able to buy it at a store somewhere and save the exorbitant shipping costs that get piled on to e-Bay stuff.

The other alternative of course is to replace everything from tank to carb with ethanol corrosion proof materials. The use of Ethanol is nothing short of a con job, but let's not go there right now!!

Geoff.

Thay Ebay product link i posted was available on ebay uk so free postage for me. As i am going concours i don't think i could use replacement ethanol corrosion proof materials.

When i first decided on concours i never imagined how the knock-on effect would affect every single decision when it comes to the importance of protecting everything. Ethanol just as one example of things i cannot do to improve/protect the car. I have to by law change to amber turn signals with a circuit board inside the reverse light cavity. I don't mean i wish i had gone restomod route. The enormity of the task ahead is only now beginning to become clear. I am sure there will be many more unknowns to come. Only today i had to have fitted differant bolts on the rag joint with nylock nuts. I have kept all the old nuts and bolts so i can put it right again when i start going deep into the strip down.

 
Thay Ebay product link i posted was available on ebay uk so free postage for me. As i am going concours i don't think i could use replacement ethanol corrosion proof materials.

When i first decided on concours i never imagined how the knock-on effect would affect every single decision when it comes to the importance of protecting everything. Ethanol just as one example of things i cannot do to improve/protect the car. I have to by law change to amber turn signals with a circuit board inside the reverse light cavity. I don't mean i wish i had gone restomod route. The enormity of the task ahead is only now beginning to become clear. I am sure there will be many more unknowns to come. Only today i had to have fitted differant bolts on the rag joint with nylock nuts. I have kept all the old nuts and bolts so i can put it right again when i start going deep into the strip down.

Steve, I admire your wish to do a concours restoration. I am definitely not trying to deter you from going that rout. However, for me, unless the car is so rare that it absolutely warrants that level of perfection (I have a 1 in 6 car and still only went to close to original appearing).

I would keep things looking original, but not going overboard. That gets waaaay tooo expensive for my blood. Fact of the matter is 99% of people viewing my car have no idea what's right or wrong as there is no chrome and fancy do-dars. Even my Holley carb can hardly be seen under the original air cleaner. I did keep all the usable parts I took off in case someone else wants to go back to factory original.

At the end of the day, it's YOUR car to restore as you see fit and good for you. You will just have to post pictures as the restoration progresses. That Grabber Lime will look awesome.

Best wishes,

Geoff.

 
Back
Top