1 - Accuracy, Repeatability, and Reliability
All of AFR’s heads are 100% CNC ported with a multi angle valve job on the intake and a fully radius valve job on the exhaust resulting in 20% or more flow than our competitors as cast and 5% or more than their CNC version. AFR's optimized, extremely efficient port and chamber designs have had hours of extensive research in the pursuit of perfection. Then they masterfully reproduce these designs on our proprietary five axis CNC porting equipment. Your local porting shop would be hard pressed to get similar numbers once by hand, never mind to copy and reproduce those results 8X in every intake and exhaust port.
Read More We offer our CNC porting in two levels to try and meet every racer’s budget and we sell our 100% CNC ported street heads for only a few hundred over most of our competitors as cast offerings. Additionally on our BBC we offer an economical bowl blend for those on a budget. There simply is NO COMPARISON when looking at airflow figures and more importantly your dyno and track numbers. Spending another few hundred dollars on AFR Cylinder Heads will double the gains you might have achieved in an effort to save money. The little bit of extra money you invest in a set of AFR’s could potentially be the best money you ever spent when you evaluate your performance gains versus dollars spent. We could just hand blend or CNC the bowls, entrances and chambers like some of our competitors, but we never take half measures at the expense of your performance results.
2 - Highest Efficiency in Their Class
AFR heads flow more than any other manufacturer when comparing heads of similar runner size and valve angles. This means a higher velocity charge with better cylinder fill and scavenging potential. The benefit of this has been independently tested and documented in many magazines, various web sites, engine shops, and various other sources as well. Simple equation
more flow and higher velocity equals more torque and more horsepower. It’s the recipe for success.
End of discussion!
3 - Exceptional Low and Mid-Lift Flow
This is what we like to refer to as “area under the curve” when it’s related to cylinder head airflow figures. Once again AFR port and combustion chamber designs excel in this area (as well as peak flow) and this is a key often overlooked in design element for performance cylinder heads. Everyone is always discussing peak flow but here is a wakeup call for you.
Read More Look at the low lift numbers more closely when comparing heads. Also, contrary to popular belief, a head with strong low and mid lift flow doesn’t mean it will have stronger power in the lower and middle part of the horsepower curve (although it will make more there), it means it will make more power everywhere due to the fact that every time an intake and exhaust valve opens and closes it will be able to move more air in total than a head with similar peak numbers and a much softer area under the curve. In fact if anything, an efficient head with better low and mid-lift flow numbers usually shows its stuff up top allowing the torque curve to hang on a little longer producing a higher peak HP figure and carry much better past peak as well (not roll over as quickly). That’s because at the higher RPM’s, when there is much less time to fill and evacuate the cylinder, airflow demand of the engine is at a premium and any little extra you cram in there (and remove) will pay you big dividends.
4 - Lifetime Warranty
AFR warranties the aluminum cylinder head casting for the lifetime to the original purchaser with proof of purchase. Additionally, valves, guides, valve seats, valve springs, valve job, retainers, locks, studs, guide plates, valve seals are warranted for two years to the original purchaser with proof of purchase.
Read More All returns must have a RMA number in order to be returned, call for a RMA number. Parts must be returned prepaid freight by the original purchaser. When it has been determined, by AFR at its sole discretion, that the product does indeed have a warrantable problem from workmanship, materials or an undetermined cause (mystery failure) AFR will repair at no charge and reimburse UPS ground freight and return UPS ground freight. AFR will repair or replace the casting at its option. This warranty doesn’t cover fitness for purpose and/or merchantability on any product sold by AFR.
This warranty does not cover the following:
- Failure due to improper installation or maintenance, abuse, misuse, unauthorized repairs, modifications, or alterations determined at the sole discretion of AFR. If your machine shop, engine builder or installer performs any unauthorized repairs, AFR warranty is voided and AFR will not reimburse any cost you incurred.
- Removal or replacement cost.
- Costs incurred due to down time of the vehicle.
- Damage to related components.
- Marine salt water corrosion.
- Corrosion from not using/refreshing antifreeze.
- Fitness for purpose or merchantability.
5 - Lightweight 8MM Valves
The smaller stem gives a slight boost in airflow but its main benefit is lighter weight which helps to reduce valve control problems commonly referred to as valve float in the most severe cases. This loss of valve control at high RPM can easily cost you 30 - 40 horsepower or more in severe cases. Not only is power reduced dramatically but reliability also becomes a concern as severe valve float can place un-do stress on the retainers, locks and valves.
Read More AFR’s 8mm valves are 15% lighter than our competitors 11/32 diameter valves which substantially reduces valve float. Valve float (or any loss of valve train control) is probably responsible for more mechanical engine failures than any other culprit. Dropped valves cause extensive engine damage! Big block Chevy heads are equipped with lighter weight 11/32 valves for all the same reasons. It’s our opinion that with the larger BBC valves, a move to 5/16 or 8mm would create reliability concerns with the head diameter and overall weight versus stem diameter. For those looking for the utmost in BBC valve control we offer titanium valves which are a fraction of the weight of their steel counter parts.
6 - Lightweight Valve Springs
See #5 above for obvious benefits! A light weight valve spring assembly (spring, retainer, and locks) has all the same benefit that reducing the mass of the valve brings to the table. The spring is also required to keep it own mass in check (in addition to the retainer and locks), and a spring that has similar seat pressures and spring rates with less total mass to control is going to extend the point your engine starts experiencing valve control related issues.
Read More All of our street/strip SBC/SBF/LSX heads come with lightweight small diameter premium wire 1.290” hydraulic roller valve springs, which also reduces the weight of the retainers due to their smaller diameter needed to meet the smaller spring requirements (the benefit of the smaller spring being compounded even further). In total, our new SBC and SBF product line has reduced the reciprocating mass of our valve train by a whopping 100 grams per cylinder! This drastic weight reduction reduces power robbing valve float issues and adds measurably to your performance engine’s reliability. AFR’s small diameter springs are made from Chrome Silicon Vanadium with Nickel and sent for a special heat treating process. Due to this process our standard spring is triple the cost of all our competitors heavy 1.400 OD spring. There is no need to spend additional money upgrading later to beehive style springs in an effort to increase your usable RPM. A quality 1.290 dual spring offers a lot more peace of mind when it comes to spring failure. With a single spring design, the likelihood of catastrophic engine damage is far greater. We have also tested our dual design directly against a leading competitor’s beehive spring revealing no difference in power till 6700 RPM (a virtual lay over of the two power curves) and a few more HP made with our dual spring design from 6700 - 7000 RPM where the testing was terminated.
7 - High Quality Springs
AFR’s entire line up of valve springs offer the end user a lot of value and peace of mind. All of our small block race applications (mechanical roller) come standard with a high quality 1.550 OD valve spring with a standard spring rate of 550lbs/inch and a maximum capacity of .710 lift. All of AFR’s larger diameter 1.550 - 1.640 springs are made from high tensile super clean Chrome Silicon that is stress relieved and also includes two stages of shot peening. They are then heat treated and 100% tested for any load loss before arriving at our facility. Due to these processes (and unlike all of our competitor’s products), we spend a lot more money on our standard spring packages resulting in a very fatigue resistant product which maintain their pressure a lot longer than springs we could source at half the price.
Read More For more aggressive applications with more cam lobe intensity and/or RPM’s, we offer premium Manley Nextek upgrade packages at affordable pricing. We are also one of the few manufacturers to offer a standard 1.625 BBC spring which receives additional stress relieving processes and is electroplate polished as well for added reliability and durability...most of our competitors entry level spring BBC springs are 1.550 diameter.
8 - Bead Lock Keepers
All AFR heads (except BBC) currently come with bead lock style valve locks for superior clamping over the conventional “square” locks our competitors use. Bead lock style locks spread the load of the spring force over a much greater percentage of the valve and valve lock’s surface area.
Read More Bead lock valve keepers offer greater reliability and less chance of lock failure (which can lead to a dropped valve and serious engine damage). We are currently implementing the change on our BBC product but it will take some time before the change is complete.
9 - Clean Sheet Design
All of AFR’s cylinder heads offer the end user a clean sheet design. This is something ported OEM and our competitor’s castings simply can’t offer. All AFR heads come with our trademarked ¾” thick head deck to meet the power demands of your aftermarket engine. We improve the water jacketing for enhanced cooling and elimination of hot spots that cause harmful detonation while retaining a minimum of .200 port to water jacket thickness. We shape and optimize our ports first, and THEN we cast our ports around the optimized superior port and chamber shapes we research to death.
Read More This also provides a secondary extremely important benefit regarding port wall thickness and integrity. A ported OEM casting will be very thin in areas and it’s very common to see leaks and at times complete port wall failure, especially in the high stressed areas. When you send your factory heads off to your local head guru, the only option they have in an effort to get you more flow is removing material and increasing the size of the port. In most situations, an OEM port design needs just as much material added in the right places as removed to net a truly effective port design that only can be achieved with a clean sheet approach that AFR uses in design.
10 - Honest Advertising
AFR stands behind all of our advertised flow numbers (to account for production tolerances, we guarantee our numbers within 2% of advertised). While some of our competitors seem to take some liberties in that department, we try our best to meet or exceed all our published data. In fact, a handful of our products actually flow notably higher than we claim.
Read More A lot of engine builders rely on our heads to deliver the power they guarantee. It is important we provide them with a head that delivers and flows as promised every time. It’s also important to note that some manufacturer’s flow their heads on different types of equipment and conveniently don’t include that information in their test results. Cylinder head flow testing equipment is no different than dyno’s; some read higher than others and a few types of equipment tend to read a lot higher. All of our heads are tested on an accurately calibrated SF600, what most still consider to be the industry standard although the SF1020 has gained a lot of popularity in recent years as well. The newer 1020 benches read very close to an SF600 model while some of the older 1020 units were a little stingier. Note all our intake data is obtained using a proper fitting radius plate with the appropriate corner radius’s (clay is not consistent), and all our exhaust data is flowed thru a curved pipe that directly simulates a typical header installed in a production vehicle (a pipe about 10” long that has an immediate curve off the exhaust flange and straightens out).
11 - Proudly Made in the USA
Here at AFR you won’t find any cheap parts made overseas. All of our castings, parts, and manufacturing is sourced and machined here in the United States.
Read More This small perk is more important than ever considering the current state of affairs we are faced with here in our country. The only exception is our extremely high quality one piece stainless valves which are manufactured in a state of the art world class factory in Argentina. If we could find the same quality valves here in the state we would buy them. For our intake valves we use 21-4N material and for our exhaust valves we use 2132 stainless which has superior properties for dealing with the excessive heat the exhaust valve is constantly subject to. Again our competitors cut corners here risking your expensive engines by saving a few bucks on cheaper materials.
12 - Wet-Flow Development
While rarely spoken about, AFR’s involvement in wet flow R&D stems back to a time when most of our competitors weren’t even in business. Ken Sperling, AFR’s founder, pioneered this study in the 1970’s and a portion of our design parameters still date back to what was learned 30+ years ago. The hard truth is that wet flow is just a small piece of the puzzle.
Read More If something has good wet flow (whatever that theoretically might be) but it doesn’t move any air, a big piece of the puzzle is missing. The key is understanding that dry flow cannot be compromised; remember there are thirteen parts air to one part fuel. There is no replacement for airflow which is the largest limiting factor in how much torque and horsepower an engine is capable of producing. We have tested our heads against some popular brands promoting wet-flow and our independent dyno results have confirmed and proved once again that more air (higher dry flow figures) generates higher power when the proper design principles are in place. Efficient, high airspeed port designs tend to take care of the fuel atomization all by themselves. Add more fuel to the extra air they are moving and the end result is more power. We know swirl, tumble, and wet flow are part of the equation but not the whole picture; so we use all these elements to design balanced ports here at AFR. The bottom line is if two heads have similar runner volume and cross section and one flows substantially more air on a flow bench than the other it will make more power every time!
13 - Proper Spring Locators
All of AFR’s product line come equipped with hardened spring seats (or cups) instead of flimsy shims that most of our competitors use which do not properly locate the valve spring. Flimsy shims get cut by the springs and then circulate metal throughout your engine.
Read More They also allow the spring to move around compromising valve control and valve guide seal life (sometimes the springs can work the seals right off the guide boss). All the cylinder heads we assemble and ship have proper spring locators (some ID style and some OD style) to positively locate the spring, keep the seals in place, and not compromise valve control for additional power.
14 - Higher Quality Valve seals
All of AFR cylinder heads are fitted with premium viton oil seals instead of cheap poly acrylic like most of our competition. Once again we try to stay a notch above our competitors and while saving a few dollars per head doesn’t sound like much, when you mass produce something the added costs add up at the end of a year.
Read More We won’t compromise the integrity of our heads to save a few dollars on parts. Cheaper poly acrylic seals will harden with heat and immediately become brittle with less ability to conform to the valve and properly control oil or worse yet they totally disintegrate and circulate that debris throughout your engine.
15 - Proven Products by a Proven Company
AFR has been in business 38 years. When you deal with us you can have a level of comfort and confidence most other companies just can’t provide. We offer real tech help by seasoned and trained individuals, not just catalog readers like some of our competition.
Read More The bottom line is we highly value customer service and do our best to uphold that goal, something a quick trip to your favorite performance message board will certainly independently confirm. Call or email us to experience firsthand the difference our top notch service can provide. You won’t be disappointed.
16 - Family Run Business
Most don’t realize but AFR is a third generation family run business. Ken Sperling, who started AFR in 1972, has a long list of accomplishments attached to his name including D-shaped BBC exhaust ports, “Hurricane chambers”, and most importantly the first company to implement CNC porting back in 1979!
Read More Ken Sperling helped the who’s who of racing make more power with names like Grumpy Jenkins, Bob Glidden, Warren Johnson, and Frank Iaconio to name a few in the drag race arena. In Nascar AFR has worked with Junior Johnson, Cale Yarbrough, Richard Petty, AJ Foyt, and Darrel Waltrip. When Ken succumbed to cancer in 1996 he passed the torch to his son Rick Sperling who had already been with the company for ten years and had helped his father in numerous capacities making him a natural to step in and head up the company. Rick has done an outstanding job in filling his Dad’s footsteps and in some ways has grown this company to a point his Dad could have only dreamed about. Rick’s son Chris is currently the head of our IT Department and is also involved in many facets of the business. He will likely fill Rick’s shoes when Rick decides to retire in the distant future.
