Help me remember if the 1974 351C engine was rated as an "Unleaded" fuel car? It seems to me the changes were made for the 1973 model year to "Unleaded"
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A "stock" 1973/1974 351C will operate just fine on US/Canadian 87 octane unleaded fuel.
quote:Originally posted by George P:
A "stock" 1973/1974 351C will operate just fine on US/Canadian 87 octane unleaded fuel.
George,
Thank you. Perhaps related but I have been chasing a metal to metal squeak/chirp coming from the engine. I pinned it down to the #3 exhaust valve. Pulled the heads and discovered they have been changed to the D0AE closed chamber heads. I had been running on the assumption they were the original heads and running unleaded fuel without additive. Fortunately no major damage and the heads will be rebuilt. Not sure if not having the additive in the fuel would cause the squeak as some of my friends believe but I'll know the heads are in good shape.
Mike , if the heads are off and off to rebuild there is a option. Up grade the valves and harden seats installed. Then lead free is a moot point.
I was lucky the care taker before me did that.
I worry about the stock valves any way with the multi groves on the stem. Driven on the street and never over rev, they may be good.
How is your engine on octane requirements? Mid grade or premium to avoid knock?
I was lucky the care taker before me did that.
I worry about the stock valves any way with the multi groves on the stem. Driven on the street and never over rev, they may be good.
How is your engine on octane requirements? Mid grade or premium to avoid knock?
If it has stock valves replace them asap.
Stock valves break without warning and will destroy the engine.
I use closed chamber 2V heads on a 351 with flat top pistons and run on 91octane standard unleaded without any problems.
It is a matter of getting the correct advance curve in the distributor.
Stock valves break without warning and will destroy the engine.
I use closed chamber 2V heads on a 351 with flat top pistons and run on 91octane standard unleaded without any problems.
It is a matter of getting the correct advance curve in the distributor.
quote:Originally posted by david 3449:
Mike , if the heads are off and off to rebuild there is a option. Up grade the valves and harden seats installed. Then lead free is a moot point.
I was lucky the care taker before me did that.
I worry about the stock valves any way with the multi groves on the stem. Driven on the street and never over rev, they may be good.
How is your engine on octane requirements? Mid grade or premium to avoid knock?
David, that was my original plans however the casting date on these heads is June of 1969, go figure. These seats are not replaceable, can only clean them up and use additive. Appreciate the thought.
quote:Originally posted by Aus Ford:
If it has stock valves replace them asap.
Stock valves break without warning and will destroy the engine.
I use closed chamber 2V heads on a 351 with flat top pistons and run on 91octane standard unleaded without any problems.
It is a matter of getting the correct advance curve in the distributor.
These are 4V closed chamber and based on the casting number they should be the ones used on the 70 351 HO engine. So I end up with those heads along with my 74 block with 4 bolt mains and hydraulic lifters along with the Sealed Power camshaft.
Talk to a machine shop.If you don't like the answer get a second op ion. I always thought the old valve seat could be cut out and a hardened seat shrunk into the head. I had a chevy small block head repaired that way.
I really don't know what heads they installed on mine but assume 72 open chamber. Looking at the build invoice $140 for lead free valve seats , in 2008. Don't know why quench heads would be exempt from this repair. We are blessed with multiple quality machine shops in our area.
I have tried to attach a photo of seats for a Windsor Ford, only for an example.
I was hoping someone would chime in with expert Cleveland advice , I learn something new here every day.
I really don't know what heads they installed on mine but assume 72 open chamber. Looking at the build invoice $140 for lead free valve seats , in 2008. Don't know why quench heads would be exempt from this repair. We are blessed with multiple quality machine shops in our area.
I have tried to attach a photo of seats for a Windsor Ford, only for an example.
I was hoping someone would chime in with expert Cleveland advice , I learn something new here every day.
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Mike,
Issue #1:
I don't know if I've ever related this story before. Even before air pollution and catalytic converters became a predominant concern, there was a movement to remove lead from gasoline because lead was poisonous. That movement had great success in 1969. That's why 1970 was the last year for high compression engines at GM, and 1971 was the last year for high compression engines at Ford. The decision to prepare for unleaded fuel at both corporations predated the Muskie act.
I worked for the Los Angeles Department of Water and Power for 36 years. I once had to have a water sampling station installed for a pipeline that ran alongside a predominant Los Angeles freeway. That installation required an EPA soil sample, as all of my new installations required. They found lead in the soil. We had to remove soil up to a depth of four feet in order to find soil below the standard for lead contamination. There was a flippin' elementary school right next to where that sampling station was located!
Leaded gasoline was not good for folks ... this had nothing to do with air pollution ... lead was poisoning our environment, it had been poisoning us, and it was poisoning our children and grand children. Of course the oil companies opposed this, they spread propaganda insisting removal of lead would wear out engines faster. That was simply bovine excrement. One of the gasoline companies, my memory makes it difficult for me to be sure, but I think it was Sunoco, argued even back in the 1960s that lead provided no "cushion" for valve seats. I believe history has proved them to be correct.
I was around in the 1970s & 1980s when the lead was pulled from the fuel, working on other people's cars. Nobody had accelerated valve wear or seat recession problems. Everybody continued to drive their cars every day, and the cars were not wearing-out at an accelerated rate. 99% of the folks did not have the heads rebuilt & retro-fitted with hardened seats. Only the folks that took popular science magazine seriously. I shake my head sometimes when I read of people still worrying about it, after 4 decades. Cripes.
I don't remember one Cleveland engine ever having valve seating issues due to unleaded fuel ... ever. Well except for the fact that Ford put an aluminum coating on the OEM 351C valves from day one, intended to provide the seat with protection ("cushioning") the engineers thought would be eliminated when lead was removed from gasoline. But the process of applying the aluminum to the valve heads made the valves brittle, which is why the valve heads occasionally develop cracks and fall off their stems even to this day. The lesson here is not that unleaded fuel created problems ... not at all ... the failure of OEM 351C valves has been a far more catastrophic problem.
Issue #2:
The information relevant for you and I today is that valve material must be compatible with valve seats and valve guides. Stainless valves (and titanium valves too) are not as "tough" as steel valves, they must be used with iron seats or beryllium copper seats ... never hardened steel. Same goes for the valve guides, use stainless valves (and titanium too) with iron guides or bronze guides.
The big issue for owners of 351C powered cars is the OEM valves ... they must be replaced to avoid catastrophic failure issues. Most people use stainless valves for replacement. In those situations folks have had good results with the valves seating upon the iron castings, and the valve stems guided in bronze valve guides. Hopefully we can move-on beyond the topic of valves and valve seats now.
Issue #3:
I don't mean to infer I don't believe you. However, I'm hoping for a photograph! If you have a set of 4V heads with a June 1969 casting date (9Fxx) I NEED a photograph of that casting date. Please.
I have never run across or even read of "production" 4V cylinder heads cast that early. The earliest so far has been July 22 (9G22). Most castings are August 1969 (9HXX) or later. A picture of a 4V head casting with a June 1969 casting date would be a cool addition to the data Cleveland enthusiasts attempt to collect regarding the 351C.
Issue #4:
I don't intend to be argumentative, simply educational. There were no 1970 351 HO engines. Period. The 351 HO engines were solid tappet engines, they had an engine code of "R" in North American Ford & Mercury cars. The engine code "R" was assigned to a different engine in 1970, the 428 Super Cobra Jet.
In 1970 a 351 with four barrel carburetor was only available as an M code engine with 10:1 compression (advertised as 11:1), a small hydraulic cam, a small 630 cfm Autolite carburetor. It was called a 351 4V, it replaced a 351W engine with the same specification and the same power rating. It was equipped with D0AE head castings with nominally 63cc combustion chambers, and machined for non-adjustable fulcrum mounted rocker arms.
The 351C M code short block was identicle to the H code (2V) short block; it had two bolt mains (although that's truly not a durability issue), flat top cast pistons, a small light-weight crankshaft damper, a standard oil pan lacking a windage tray, and a single point distributor.
Issue #1:
I don't know if I've ever related this story before. Even before air pollution and catalytic converters became a predominant concern, there was a movement to remove lead from gasoline because lead was poisonous. That movement had great success in 1969. That's why 1970 was the last year for high compression engines at GM, and 1971 was the last year for high compression engines at Ford. The decision to prepare for unleaded fuel at both corporations predated the Muskie act.
I worked for the Los Angeles Department of Water and Power for 36 years. I once had to have a water sampling station installed for a pipeline that ran alongside a predominant Los Angeles freeway. That installation required an EPA soil sample, as all of my new installations required. They found lead in the soil. We had to remove soil up to a depth of four feet in order to find soil below the standard for lead contamination. There was a flippin' elementary school right next to where that sampling station was located!
Leaded gasoline was not good for folks ... this had nothing to do with air pollution ... lead was poisoning our environment, it had been poisoning us, and it was poisoning our children and grand children. Of course the oil companies opposed this, they spread propaganda insisting removal of lead would wear out engines faster. That was simply bovine excrement. One of the gasoline companies, my memory makes it difficult for me to be sure, but I think it was Sunoco, argued even back in the 1960s that lead provided no "cushion" for valve seats. I believe history has proved them to be correct.
I was around in the 1970s & 1980s when the lead was pulled from the fuel, working on other people's cars. Nobody had accelerated valve wear or seat recession problems. Everybody continued to drive their cars every day, and the cars were not wearing-out at an accelerated rate. 99% of the folks did not have the heads rebuilt & retro-fitted with hardened seats. Only the folks that took popular science magazine seriously. I shake my head sometimes when I read of people still worrying about it, after 4 decades. Cripes.
I don't remember one Cleveland engine ever having valve seating issues due to unleaded fuel ... ever. Well except for the fact that Ford put an aluminum coating on the OEM 351C valves from day one, intended to provide the seat with protection ("cushioning") the engineers thought would be eliminated when lead was removed from gasoline. But the process of applying the aluminum to the valve heads made the valves brittle, which is why the valve heads occasionally develop cracks and fall off their stems even to this day. The lesson here is not that unleaded fuel created problems ... not at all ... the failure of OEM 351C valves has been a far more catastrophic problem.
Issue #2:
The information relevant for you and I today is that valve material must be compatible with valve seats and valve guides. Stainless valves (and titanium valves too) are not as "tough" as steel valves, they must be used with iron seats or beryllium copper seats ... never hardened steel. Same goes for the valve guides, use stainless valves (and titanium too) with iron guides or bronze guides.
The big issue for owners of 351C powered cars is the OEM valves ... they must be replaced to avoid catastrophic failure issues. Most people use stainless valves for replacement. In those situations folks have had good results with the valves seating upon the iron castings, and the valve stems guided in bronze valve guides. Hopefully we can move-on beyond the topic of valves and valve seats now.
Issue #3:
I don't mean to infer I don't believe you. However, I'm hoping for a photograph! If you have a set of 4V heads with a June 1969 casting date (9Fxx) I NEED a photograph of that casting date. Please.
I have never run across or even read of "production" 4V cylinder heads cast that early. The earliest so far has been July 22 (9G22). Most castings are August 1969 (9HXX) or later. A picture of a 4V head casting with a June 1969 casting date would be a cool addition to the data Cleveland enthusiasts attempt to collect regarding the 351C.
Issue #4:
I don't intend to be argumentative, simply educational. There were no 1970 351 HO engines. Period. The 351 HO engines were solid tappet engines, they had an engine code of "R" in North American Ford & Mercury cars. The engine code "R" was assigned to a different engine in 1970, the 428 Super Cobra Jet.
In 1970 a 351 with four barrel carburetor was only available as an M code engine with 10:1 compression (advertised as 11:1), a small hydraulic cam, a small 630 cfm Autolite carburetor. It was called a 351 4V, it replaced a 351W engine with the same specification and the same power rating. It was equipped with D0AE head castings with nominally 63cc combustion chambers, and machined for non-adjustable fulcrum mounted rocker arms.
The 351C M code short block was identicle to the H code (2V) short block; it had two bolt mains (although that's truly not a durability issue), flat top cast pistons, a small light-weight crankshaft damper, a standard oil pan lacking a windage tray, and a single point distributor.
quote:Originally posted by George P:
Mike,
Issue #1:
I don't know if I've ever related this story before. Even before air pollution and catalytic converters became a predominant concern, there was a movement to remove lead from gasoline because lead was poisonous. That movement had great success in 1969. That's why 1970 was the last year for high compression engines at GM, and 1971 was the last year for high compression engines at Ford. The decision to prepare for unleaded fuel at both corporations predated the Muskie act.
I worked for the Los Angeles Department of Water and Power for 36 years. I once had to have a water sampling station installed for a pipeline that ran alongside a predominant Los Angeles freeway. That installation required an EPA soil sample, as all of my new installations required. They found lead in the soil. We had to remove soil up to a depth of four feet in order to find soil below the standard for lead contamination. There was a flippin' elementary school right next to where that sampling station was located!
Leaded gasoline was not good for folks ... this had nothing to do with air pollution ... lead was poisoning our environment, it had been poisoning us, and it was poisoning our children and grand children. Of course the oil companies opposed this, they spread propaganda insisting removal of lead would wear out engines faster. That was simply bovine excrement. One of the gasoline companies, my memory makes it difficult for me to be sure, but I think it was Sunoco, argued even back in the 1960s that lead provided no "cushion" for valve seats. I believe history has proved them to be correct.
I was around in the 1970s & 1980s when the lead was pulled from the fuel, working on other people's cars. Nobody had accelerated valve wear or seat recession problems. Everybody continued to drive their cars every day, and the cars were not wearing-out at an accelerated rate. 99% of the folks did not have the heads rebuilt & retro-fitted with hardened seats. Only the folks that took popular science magazine seriously. I shake my head sometimes when I read of people still worrying about it, after 4 decades. Cripes.
I don't remember one Cleveland engine ever having valve seating issues due to unleaded fuel ... ever. Well except for the fact that Ford put an aluminum coating on the OEM 351C valves from day one, intended to provide the seat with protection ("cushioning") the engineers thought would be eliminated when lead was removed from gasoline. But the process of applying the aluminum to the valve heads made the valves brittle, which is why the valve heads occasionally develop cracks and fall off their stems even to this day. The lesson here is not that unleaded fuel created problems ... not at all ... the failure of OEM 351C valves has been a far more catastrophic problem.
Issue #2:
The information relevant for you and I today is that valve material must be compatible with valve seats and valve guides. Stainless valves (and titanium valves too) are not as "tough" as steel valves, they must be used with iron seats or beryllium copper seats ... never hardened steel. Same goes for the valve guides, use stainless valves (and titanium too) with iron guides or bronze guides.
The big issue for owners of 351C powered cars is the OEM valves ... they must be replaced to avoid catastrophic failure issues. Most people use stainless valves for replacement. In those situations folks have had good results with the valves seating upon the iron castings, and the valve stems guided in bronze valve guides. Hopefully we can move-on beyond the topic of valves and valve seats now.
Issue #3:
I don't mean to infer I don't believe you. However, I'm hoping for a photograph! If you have a set of 4V heads with a June 1969 casting date (9Fxx) I NEED a photograph of that casting date. Please.
I have never run across or even read of "production" 4V cylinder heads cast that early. The earliest so far has been July 22 (9G22). Most castings are August 1969 (9HXX) or later. A picture of a 4V head casting with a June 1969 casting date would be a cool addition to the data Cleveland enthusiasts attempt to collect regarding the 351C.
Issue #4:
I don't intend to be argumentative, simply educational. There were no 1970 351 HO engines. Period. The 351 HO engines were solid tappet engines, they had an engine code of "R" in North American Ford & Mercury cars. The engine code "R" was assigned to a different engine in 1970, the 428 Super Cobra Jet.
In 1970 a 351 with four barrel carburetor was only available as an M code engine with 10:1 compression (advertised as 11:1), a small hydraulic cam, a small 630 cfm Autolite carburetor. It was called a 351 4V, it replaced a 351W engine with the same specification and the same power rating. It was equipped with D0AE head castings with nominally 63cc combustion chambers, and machined for a hydraulic tappet cam.
The 351C M code short block was identicle to the H code (2V) short block; it had two bolt mains (although that's truly not a durability issue), flat top cast pistons, a small light-weight crankshaft damper, a standard oil pan lacking a windage tray, and a single point distributor.
George,
You are correct I read that incorrectly as being an HO which it would not be.
I hope to have the heads back tomorrow or Monday and I'll get a picture of the casting date for you.
Of course this all started by trying to find the metal to metal chirping noise when hot. When I pushed on #3 rocker the noise would go away, new rocker and fulcrum did not cure the noise. Next step to me was something in the head, perhaps the guides which did show signs of wear out. I also wanted to verify what valve were in the heads which were the OEM valve. So I'm have the valve replaced and new guides installed. May or may not resolve the noise but I'll have confidence in the heads now.
Woah! There's a wealth of information there.
I've been told here in AU to run mine on the "premium" 98 octane fuel here because of the engine age. Which of course I'm happy to do - cleaner burn and more power
.
I remember the change from leaded to unleaded here and the controversy over the potential damage to engines that would definitely occur if you didn't change valves and seats etc...
The thing I remember most though was the rotten egg smell of the "new cars"...
I've been told here in AU to run mine on the "premium" 98 octane fuel here because of the engine age. Which of course I'm happy to do - cleaner burn and more power
. I remember the change from leaded to unleaded here and the controversy over the potential damage to engines that would definitely occur if you didn't change valves and seats etc...
The thing I remember most though was the rotten egg smell of the "new cars"...
quote:Originally posted by George P:
Mike,
Issue #1:
I don't know if I've ever related this story before. Even before air pollution and catalytic converters became a predominant concern, there was a movement to remove lead from gasoline because lead was poisonous. That movement had great success in 1969. That's why 1970 was the last year for high compression engines at GM, and 1971 was the last year for high compression engines at Ford. The decision to prepare for unleaded fuel at both corporations predated the Muskie act.
I worked for the Los Angeles Department of Water and Power for 36 years. I once had to have a water sampling station installed for a pipeline that ran alongside a predominant Los Angeles freeway. That installation required an EPA soil sample, as all of my new installations required. They found lead in the soil. We had to remove soil up to a depth of four feet in order to find soil below the standard for lead contamination. There was a flippin' elementary school right next to where that sampling station was located!
Leaded gasoline was not good for folks ... this had nothing to do with air pollution ... lead was poisoning our environment, it had been poisoning us, and it was poisoning our children and grand children. Of course the oil companies opposed this, they spread propaganda insisting removal of lead would wear out engines faster. That was simply bovine excrement. One of the gasoline companies, my memory makes it difficult for me to be sure, but I think it was Sunoco, argued even back in the 1960s that lead provided no "cushion" for valve seats. I believe history has proved them to be correct.
I was around in the 1970s & 1980s when the lead was pulled from the fuel, working on other people's cars. Nobody had accelerated valve wear or seat recession problems. Everybody continued to drive their cars every day, and the cars were not wearing-out at an accelerated rate. 99% of the folks did not have the heads rebuilt & retro-fitted with hardened seats. Only the folks that took popular science magazine seriously. I shake my head sometimes when I read of people still worrying about it, after 4 decades. Cripes.
I don't remember one Cleveland engine ever having valve seating issues due to unleaded fuel ... ever. Well except for the fact that Ford put an aluminum coating on the OEM 351C valves from day one, intended to provide the seat with protection ("cushioning") the engineers thought would be eliminated when lead was removed from gasoline. But the process of applying the aluminum to the valve heads made the valves brittle, which is why the valve heads occasionally develop cracks and fall off their stems even to this day. The lesson here is not that unleaded fuel created problems ... not at all ... the failure of OEM 351C valves has been a far more catastrophic problem.
Issue #2:
The information relevant for you and I today is that valve material must be compatible with valve seats and valve guides. Stainless valves (and titanium valves too) are not as "tough" as steel valves, they must be used with iron seats or beryllium copper seats ... never hardened steel. Same goes for the valve guides, use stainless valves (and titanium too) with iron guides or bronze guides.
The big issue for owners of 351C powered cars is the OEM valves ... they must be replaced to avoid catastrophic failure issues. Most people use stainless valves for replacement. In those situations folks have had good results with the valves seating upon the iron castings, and the valve stems guided in bronze valve guides. Hopefully we can move-on beyond the topic of valves and valve seats now.
Issue #3:
I don't mean to infer I don't believe you. However, I'm hoping for a photograph! If you have a set of 4V heads with a June 1969 casting date (9Fxx) I NEED a photograph of that casting date. Please.
I have never run across or even read of "production" 4V cylinder heads cast that early. The earliest so far has been July 22 (9G22). Most castings are August 1969 (9HXX) or later. A picture of a 4V head casting with a June 1969 casting date would be a cool addition to the data Cleveland enthusiasts attempt to collect regarding the 351C.
Issue #4:
I don't intend to be argumentative, simply educational. There were no 1970 351 HO engines. Period. The 351 HO engines were solid tappet engines, they had an engine code of "R" in North American Ford & Mercury cars. The engine code "R" was assigned to a different engine in 1970, the 428 Super Cobra Jet.
In 1970 a 351 with four barrel carburetor was only available as an M code engine with 10:1 compression (advertised as 11:1), a small hydraulic cam, a small 630 cfm Autolite carburetor. It was called a 351 4V, it replaced a 351W engine with the same specification and the same power rating. It was equipped with D0AE head castings with nominally 63cc combustion chambers, and machined for a hydraulic tappet cam.
The 351C M code short block was identicle to the H code (2V) short block; it had two bolt mains (although that's truly not a durability issue), flat top cast pistons, a small light-weight crankshaft damper, a standard oil pan lacking a windage tray, and a single point distributor.
I got the heads back today. He must have read the date code incorrectly, or upside down, when he told me as these are both D0AE 9J heads. As I make it out that would make them September of 1969 castings.
my 2nd / 3rd hand understanding is that the 351C heads require a shallow seat insert to avoid hitting water during the machining operation. most shops have their own 'go to' seat inserts that are probably fairly thick & substantial & know that those inserts will hit water so they simply say it can't be done
a fellow on 351C.net & other forums, Bill Diehl, runs a stock class bracket racing car is Heavy into reworking his heads within class rules & has successfully replaced all 16 seats as the basis for his air flow work. Steve K has also just recently replicated Bill's valve seat replacement recipe
it can be done with the right inserts, if you need to?
if you have stock valves & are looking to replace them before they dictate your next new engine, you can simply order a slightly larger diameter valve & move the actual seat angle out to fresh material
Yes I've had the displeasure of a valve head separation
and Yes I agree with George that The Sky Is Not Falling in the valve seat recession dept.
the removal of lead from the fuel blend did cause a need to tune differently, as did the introduction of EFI with its' recipe change to optimize fuel atomization from injectors (not necessarily good for carbs) ... now we have another major change to the blend with the various concentrations of ethanol. the fuel blend is constantly changing, watch your Specific Gravity!
a fellow on 351C.net & other forums, Bill Diehl, runs a stock class bracket racing car is Heavy into reworking his heads within class rules & has successfully replaced all 16 seats as the basis for his air flow work. Steve K has also just recently replicated Bill's valve seat replacement recipe
it can be done with the right inserts, if you need to?
if you have stock valves & are looking to replace them before they dictate your next new engine, you can simply order a slightly larger diameter valve & move the actual seat angle out to fresh material
Yes I've had the displeasure of a valve head separation
and Yes I agree with George that The Sky Is Not Falling in the valve seat recession dept.
the removal of lead from the fuel blend did cause a need to tune differently, as did the introduction of EFI with its' recipe change to optimize fuel atomization from injectors (not necessarily good for carbs) ... now we have another major change to the blend with the various concentrations of ethanol. the fuel blend is constantly changing, watch your Specific Gravity!