Head Gaskets on 94/95 SC
- Thread starter cowtown
- Start date
Hg
The problem with the head gaskets is in the design. I dont think the gasket was designed well enough to stand the mating of aluminum heads on the iron block. I dont think the gasket design was changed for 94/95, on top of that, you are forcing 12psi in to your engine. So, it is possible to blow the HG without mods. I did mine just for the hell of it because there were 141K on the engine and the gasket had yet to be replaced. When I took it off, The same cylinder that blew in the other 2 t-birds ive done was about to break through. So in short, my advice would be to just wait, or if you know how just do it! haha good luck
The problem with the head gaskets is in the design. I dont think the gasket was designed well enough to stand the mating of aluminum heads on the iron block. I dont think the gasket design was changed for 94/95, on top of that, you are forcing 12psi in to your engine. So, it is possible to blow the HG without mods. I did mine just for the hell of it because there were 141K on the engine and the gasket had yet to be replaced. When I took it off, The same cylinder that blew in the other 2 t-birds ive done was about to break through. So in short, my advice would be to just wait, or if you know how just do it! haha good luck
Its better, but definately not a non-issue.
Headgaskets are nothing to lose sleep over, they are not that hard to do. They just take time. Unless you have absolutely no other form of transportation or spare cash, you really shouldnt worry that much. Just get a better exhaust, keep it cool, and keep the boost no higher than 15psi and they should last awhile.
Headgaskets are nothing to lose sleep over, they are not that hard to do. They just take time. Unless you have absolutely no other form of transportation or spare cash, you really shouldnt worry that much. Just get a better exhaust, keep it cool, and keep the boost no higher than 15psi and they should last awhile.
A little more background.
Aluminum heads and Iron block combo's have been prone to Early HG failures. Blow boost on it and you're asking for trouble.
Yet, manufacturers find the Aluminum head/Iron block combo quite lucrative from a price/production/profit standpoint.
The main problems with the Supercoupe (and the 3.8 in general) were very early headgasket failures. Failures that were occuring on the earlier birds around 40-50K miles. This prompted many customers to have the impression that as soon as their factory warranty ends, they are saddled with a bill or purchasing a new car.
In a attempt to reduce service warranty issues and allow customers to get a "reasonable" lifetime out of their cars, Ford turned to Fel-Pro to supply the stock headgaskets for the 94-95 SC's. The Fel-pro gasket was a bit stronger than the Original ford ones and was manufactured to tighter tolerances.
To make it look like Ford cared, they also backed it up with a 7year/100,000miles warranty on the headgaskets. But the Warranty was meaningless, since the 94-95 cars weren't the issue.
Regardless though, just about any car with a Iron block/Aluminum head combo will eat away it's headgaskets eventually. The difference now is either 40K miles for a 89-93 Bird or 140K miles for a 94-95.
The way to make things really last are when you perform the rebuild. Make sure the heads and block are flat. Surprisingly, many Birds left the factory with tolerances that were "less than optimum" regarding this dimension. Use a high quality gasket, there are several options to choose from. Use the stronger ARP head studs, as they are less prone to stretching, they are reuseable and this will keep the head from warping as easily. And lastly, pay attention to cooling. Many of the "Red" formulation anti-freezes that we see on cars today are not only extended life coolants but were also formulated to reduce the natural electrolysis that occurs, which eats away headgaskets from the cooling side of the system and thus weakens them. Of course, good tuning, quality fuel and special attention to boost/intercooling will pay dividends to keep you out of detonation which is a major cause of headgasket failure.
Aluminum heads and Iron block combo's have been prone to Early HG failures. Blow boost on it and you're asking for trouble.
Yet, manufacturers find the Aluminum head/Iron block combo quite lucrative from a price/production/profit standpoint.
The main problems with the Supercoupe (and the 3.8 in general) were very early headgasket failures. Failures that were occuring on the earlier birds around 40-50K miles. This prompted many customers to have the impression that as soon as their factory warranty ends, they are saddled with a bill or purchasing a new car.
In a attempt to reduce service warranty issues and allow customers to get a "reasonable" lifetime out of their cars, Ford turned to Fel-Pro to supply the stock headgaskets for the 94-95 SC's. The Fel-pro gasket was a bit stronger than the Original ford ones and was manufactured to tighter tolerances.
To make it look like Ford cared, they also backed it up with a 7year/100,000miles warranty on the headgaskets. But the Warranty was meaningless, since the 94-95 cars weren't the issue.
Regardless though, just about any car with a Iron block/Aluminum head combo will eat away it's headgaskets eventually. The difference now is either 40K miles for a 89-93 Bird or 140K miles for a 94-95.
The way to make things really last are when you perform the rebuild. Make sure the heads and block are flat. Surprisingly, many Birds left the factory with tolerances that were "less than optimum" regarding this dimension. Use a high quality gasket, there are several options to choose from. Use the stronger ARP head studs, as they are less prone to stretching, they are reuseable and this will keep the head from warping as easily. And lastly, pay attention to cooling. Many of the "Red" formulation anti-freezes that we see on cars today are not only extended life coolants but were also formulated to reduce the natural electrolysis that occurs, which eats away headgaskets from the cooling side of the system and thus weakens them. Of course, good tuning, quality fuel and special attention to boost/intercooling will pay dividends to keep you out of detonation which is a major cause of headgasket failure.
Here's a thought-
With the iron block and aluminum heads exposed to the ethylene glycol coolant, we probably see some degree of galvanic corrosion that takes place in the headgaskets, correct?
So-if we run a car that has the hardened SCE Pro-Seal Copper gaskets, and find a way to mount a pair of zincs in the coolant passages near the heads, maybe that would cure the problem??
Of course you would need the zincs mounted in an easily accessed area, since you would need to replace them every year.
Just sitting here with the brain in OD
With the iron block and aluminum heads exposed to the ethylene glycol coolant, we probably see some degree of galvanic corrosion that takes place in the headgaskets, correct?
So-if we run a car that has the hardened SCE Pro-Seal Copper gaskets, and find a way to mount a pair of zincs in the coolant passages near the heads, maybe that would cure the problem??
Of course you would need the zincs mounted in an easily accessed area, since you would need to replace them every year.
Just sitting here with the brain in OD
Big Cat Davo
Registered User
Engine Temps
Keep the engine temps down and do the exhasut before you add boost or a better super charger and you headsgaskets should be ok. I have 250,000 KMS on my Cat, stock HG's. I have wired up my rad fan to have direct control over it, so I never let the engine temps stay above the N for too long, keep the car nice and cool.
Dave
Keep the engine temps down and do the exhasut before you add boost or a better super charger and you headsgaskets should be ok. I have 250,000 KMS on my Cat, stock HG's. I have wired up my rad fan to have direct control over it, so I never let the engine temps stay above the N for too long, keep the car nice and cool.
Dave
What I was specifically referring to...
Is GM's original introduction of "Dex-Cool". Although I don't know all of the water chemistry behind it, it was formulated to be not only a better absorber and rejector of heat, it was able to last 5years or 150,000miles.
Now, one of the reasons why manufacturers originally recommended Bi-annual coolant flushes was to reduce the electrolysis that would take place between the aluminum in the heads and the brass (or copper?) in the radiator.
Combined with high temperature and pressure, this condtion would transform the aluminum in the cooling system and the metals in the radiator into a anode and cathode. There would be a stripping of metal from one source (the aluminum in the heads) and a deposit of it in the radiator. If you were to take a volt-meter and stick the probes into the coolant of the radiator, you would measure anywhere from 0.5-1.0 Volt.
The process is slow and can take years to see any visible effect, but one of the main areas that it attacks are the thin metal rings on the headgaskets. Once those would corrode on the coolant side of things, the coolant will soak the gasket itself and weaken it.
ALso, the enhanced cooling of "Dex-cool" and it's higher latent heat of vaporization would help prevent loaclized boiling around pockets in the heads. This would go on to reduce hot spots in the combustion chamber and therefore reduce the chances of detonation. Another headgasket destroyer.
But the big long term enemy of headgaskets in a disimilar metal engine are the different expansion and contraction rates of the metals. This plainly physically damages the gasket and "wears" it out. Over many years of heating and cooling cycles, the headgaskets no longer seal the tolerances and this leads to small leaks that get bigger and lead to eventuall total failure. Again, "Dex-Cool" by keeping temps more regulated, prevented as much expansion and contraction of the metals in the engine and this went on to helping the engine last longer.
Obviously "Dex-cool" has been modified significantly over the years and is now sold over the counter along with Ford's equivilents. Ford even has a severe duty "Yellow" coolant that they use in the Power Stroke diesels that is supposedly even better.
At any rate, I personally run "Prestone Extended Life Coolant" in my SC I run a 40% Coolant / 60% Water solution. It is "Dex-cool" compatable, as well as being standard Ethylene Glycol compatable (something that the original Dex-cool was not , requireing a thourogh flush of the system).
I've noticed a slight bit better cooling than the standard coolant and I know that I can keep it in my engine if I wanted to longer than 2 years. However, I'll probably be flushing it out next year just to be on the safe side....
If you want a serious coolant, try "Evans NPG". Go to www.evanscooling.com for more information on this amazing "non-H20" coolant.
Is GM's original introduction of "Dex-Cool". Although I don't know all of the water chemistry behind it, it was formulated to be not only a better absorber and rejector of heat, it was able to last 5years or 150,000miles.
Now, one of the reasons why manufacturers originally recommended Bi-annual coolant flushes was to reduce the electrolysis that would take place between the aluminum in the heads and the brass (or copper?) in the radiator.
Combined with high temperature and pressure, this condtion would transform the aluminum in the cooling system and the metals in the radiator into a anode and cathode. There would be a stripping of metal from one source (the aluminum in the heads) and a deposit of it in the radiator. If you were to take a volt-meter and stick the probes into the coolant of the radiator, you would measure anywhere from 0.5-1.0 Volt.
The process is slow and can take years to see any visible effect, but one of the main areas that it attacks are the thin metal rings on the headgaskets. Once those would corrode on the coolant side of things, the coolant will soak the gasket itself and weaken it.
ALso, the enhanced cooling of "Dex-cool" and it's higher latent heat of vaporization would help prevent loaclized boiling around pockets in the heads. This would go on to reduce hot spots in the combustion chamber and therefore reduce the chances of detonation. Another headgasket destroyer.
But the big long term enemy of headgaskets in a disimilar metal engine are the different expansion and contraction rates of the metals. This plainly physically damages the gasket and "wears" it out. Over many years of heating and cooling cycles, the headgaskets no longer seal the tolerances and this leads to small leaks that get bigger and lead to eventuall total failure. Again, "Dex-Cool" by keeping temps more regulated, prevented as much expansion and contraction of the metals in the engine and this went on to helping the engine last longer.
Obviously "Dex-cool" has been modified significantly over the years and is now sold over the counter along with Ford's equivilents. Ford even has a severe duty "Yellow" coolant that they use in the Power Stroke diesels that is supposedly even better.
At any rate, I personally run "Prestone Extended Life Coolant" in my SC I run a 40% Coolant / 60% Water solution. It is "Dex-cool" compatable, as well as being standard Ethylene Glycol compatable (something that the original Dex-cool was not , requireing a thourogh flush of the system).
I've noticed a slight bit better cooling than the standard coolant and I know that I can keep it in my engine if I wanted to longer than 2 years. However, I'll probably be flushing it out next year just to be on the safe side....
If you want a serious coolant, try "Evans NPG". Go to www.evanscooling.com for more information on this amazing "non-H20" coolant.
ThunderDave
Registered User
As far as aluminum heads on iron block go, the N/A 3.8 have a problem with blowing head gaskets too. So as much pressure as the SC 3.8 has put on it, it just a matter of time, modding or no modding. Best if you can do it before they blow and cause possible damage to the lower end by coolant getting in the oil.
I was under the impression that Ford had made improvements to the design by the time the 94/95 came out, but I wouldn't trust that as reassurance.
David
I was under the impression that Ford had made improvements to the design by the time the 94/95 came out, but I wouldn't trust that as reassurance.
David
Read my earlier post...
Ford did contract with Fel-pro for a slightly improved gasket for the 94/95 SC birds in order to stand up to the stress that a "typical OEM" application should.
If your car blew it's HG at 40K miles, you'd be back at the dealer raising Hell.
But if it blew the HG at 140K, the dealer would laugh in your face. At that point, you've gotten a "reasonable" lifetime out of the engine and car they would be directing you to the new cars to purchase.
THAT was why ford improved the design of the gaskets.
ALso, there were some other improvements made too, such as the supercharger itself that was spun slightly slower, thus generating less heat. A cooler intake charge is going to result in reduced chances of detonation.
Little things like that also added up to be a more "reliable" package.
Ford did contract with Fel-pro for a slightly improved gasket for the 94/95 SC birds in order to stand up to the stress that a "typical OEM" application should.
If your car blew it's HG at 40K miles, you'd be back at the dealer raising Hell.
But if it blew the HG at 140K, the dealer would laugh in your face. At that point, you've gotten a "reasonable" lifetime out of the engine and car they would be directing you to the new cars to purchase.
THAT was why ford improved the design of the gaskets.
ALso, there were some other improvements made too, such as the supercharger itself that was spun slightly slower, thus generating less heat. A cooler intake charge is going to result in reduced chances of detonation.
Little things like that also added up to be a more "reliable" package.