The Last Head Gasket You Need to Buy
Shop Now ->
If you are an engine builder, racer, or car enthusiast, you’ve probably found that the Achilles Heel of high-powered engines is the head gasket. Its notorious location between the top of the bore and the combustion chamber means that it sees the most extreme pressures that an engine can generate – even in an unmodified engine. Along with the head gaskets duty of sealing cylinder pressure, it must also seal the coolant and oil passages that pass through it. This means that when the head gasket seal is breached, fluids can end up where they are not supposed to, combustion can end up where it’s not supposed to, and in extreme cases lead to hydro-locked cylinders, blown up radiators, or complete engine failure.
Lifting the head
If you’re reading this you’ve likely experienced a lifted head. A lifted head is not simply the head lifting up off the deck in one smooth motion because of too much timing or boost pressure. It’s actually more like the combustion chamber “recoiling” off the deck surface by a tiny amount with each combustion event. In real time, this “recoil” causes the head to vibrate up off the deck surface around the combustion chamber in areas where there is less clamping force, usually away from a head bolt or stud. The momentary window created by this vibration allows combustion pressure to blast its way out through the path of least resistance. Since the cylinders are surrounded by coolant, the combustion has no where else to go but into the coolant gallery. This is what results in an engine building excessive coolant pressure under power, pushing coolant out of the cap, overheating, or in extreme cases ruptured coolant lines or tanks, torched heads, water getting drawn back into the cylinder under decel, you name it. Many learn to live with it by changing head gaskets as often as they change oil.
How it’s normally fixed
The standard protocol for improving a head gasket seal on a high HP engine build is to start with aftermarket head studs. This will only take you so far because the soft aluminum cylinder head can still flex in between the head studs, and this “recoiling” effect can still take place. Even perfectly flat block and deck surfaces are in fact not flat once the engine is singing at high rpm and high boost.
The second line of defense is to buy a better aftermarket MLS head gasket, or better yet a cut-ring type head gasket. This is often a solution for medium powered engines but still doesn’t remove the possibility of head gasket failure since there is still nowhere for the combustion to go if the combustion seal is compromised.
Finally for the most extreme racers, steel o-rings, fire rings with receiver grooves and copper plates, gas rings with o-ringed coolant galleries, the list goes on of expensive head gasket solutions. These solutions are costly in machine work but function rather well. But again, some still end up pressurizing coolant due to a detonation event or some kind of tuning mishap because you can’t stop the cylinder head from recoiling and flexing.
The VFR Head Gasket solution
VFR stands for Vented Fire Ring. These head gaskets are designed to not allow combustion pressure into the cooling system under any circumstance. They require no special machining, and can be installed on a standard deck/head surface. Initially designed for our 700hp time attack car that sees upwards of 40psi of boost during hot laps, we have extensively tested and proven this head gasket solution since it’s first prototype in 2019.
The VFR head gasket is comprised of self cutting chrome steel fire rings, and stainless-steel coolant/oil sealing plate(s) with integrated leak paths "vents" for each fire ring. These integrated vents create escape paths to atmosphere for any possible combustion leakage. Installation involves sealant application to the stainless-steel plate, and sticking the fire rings in place around the bores with adhesive. Since there are no crush items in this gasket, it is completely reusable.
It is believed that the idea of venting fire rings originated in the turbo F1 and Group C era, when boost pressures were extreme and cars needed some way to complete the full length of a GP without mechanical failure. This idea has been kept mostly a secret, and is still found in the pro race engines of today. The vents would be machined into the deck surface, with o-rings or composite gaskets present to seal coolant/oil passages. The VFR Gasket offers this same functionality in just a plate, rings, and sealant with no complicated machining needed to achieve the same result.
The need for vents
The belief that head gaskets that use fire rings never leak combustion is simply false. In the same way that the cylinder head recoils and flexes with a normal head gasket, it will do the same even with beefy fire rings and extreme clamping force. The only advantage of fire rings is that when they leak, they leak a tiny amount and then reseal without any damage. Sounds great, but without vents that fire ring just pushed combustion into the cooling system.
The addition of vents makes the fire ring system truly ideal. Bad combustion events can happen that lift the head beyond what the ring can seal, the excess pressure can escape through the side of the deck, and then the ring can reseal and everything functions normally again. Since the vents offer an atmospheric isolation between the fire rings and the coolant sealing plate, it’s impossible for coolant to enter a cylinder as well.
What could you do with a better head gasket?
Eliminating the head gasket as a failure point means that you can run more boost, more aggressive tuning, and as a result make more HP without having to worry about a head gasket failure costing you time, money, or a race win.