RHS is the leading developer of high performance cylinder heads, engine blocks, intake manifolds and related components for street performance and race engines Racing Head Service (RHS) JavaScript seems to be disabled in your browser. *Note that this is an approximate RPM range guideline only –there are too many individual engine variables such as: rod length and bore/stroke ratio, rotating assembly weight, valvetrain weight, induction, camshaft characteristics, tuning, and many others that will have a tremendous impact on the RPM range of a given engine to offer more than a general prediction of powerband and upper-rpm capability. Although Racing Head Service® offers many different intake runner volumes in its cylinder heads, chances are that only one or two of them are appropriate for your application. Flow numbers hit an amazing 390 cfm at .700-inch lift, unheard of for an LS3-style port. Remember that velocity produces low rpm torque, and flow produces high rpm horsepower. Second in size only to the LS3 Mast heads, the … There was a set on Ebay last week, The guy did some mild porting and polished them up. The head is equipped with 2.08/1.60-inch valves and despite the rather large intake valve, still creates over 100 cfm/sq.in. 1.54" exh. head. The aluminum LS-series heads from RHS offer superior flow and power production thanks to precision CNC porting. ... All flow numbers for Sabre Heads come from their Web Site. So that 170cc cylinder head that you’ve been looking at -with its smaller, higher-velocity runners and valves, is going to accelerate well from a stop, produce lots of low speed torque, and be a great performer below 6000 RPM (which covers about 97% of all street-performance scenarios), but it may not reach the peak RPM you’d want in say, a drag race engine. A buddy of mine has a set of the RHS heads here in town, still bare. RHS is the leading developer of high performance cylinder heads, engine blocks, intake manifolds and related components for street performance and race engines These heads deliver more features, higher flow characteristics and better finish quality than other competitive brands. Conversely, that high–flowing 235cc Small Block Chevy cylinder head that your friends tell you is all the rage at the local track is going to help your engine to rev like crazy and produce a ton of upper rpm horsepower, but it won’t build power below 3500 RPM -making it virtually unusable on the street. The flow numbers rival any ported LS7 head as a result, yet it is still compatible with LS3 valvetrain components and intake manifolds. RHS offers the Pro-Action heads (formerly called Cylcone) in three intake runner volumes, 180cc (back), 200cc (not shown), and 215cc (foreground). We flow them on a Superflow 600 flow bench at 28" of depression and use a 4.030 bore. Hardware: Varies Rocker Mount Type: Press in stud Runner Volumes: est 140cc int. I just flowed an RHS aluminum 360cc head right out of the box. Both port sizes feature 121cc combustion chambers and 1.880″ exhaust seats, with the 339cc heads taking a 2.250″ intake valve, and a 2.300″ valve on the 376cc version. Most experts will tell you that the answer is not “bigger is better”, but rather that you should run the correct heads for your application with components (cam, intake, exhaust system, etc.) The numbers posted by Pro Topline are probably on a 4.125 bore. Richard Holdener tests the RHS aluminum cylinder heads and a mild COMP cam in this episode of Speed Secrets. * Flow data for this head from an external source. These large runner, high flow heads are custom built by FTI from RHS Pro Action cylinder head castings. I can get the 235 AFR heads up to 350 CFM, for comparission sake. So if you’re looking to build an all-out race car that will never see street duty, that 235cc head with compression, cam, induction, and drivetrain to match will have you winning races in no time. No swirl numbers available. The new Air Flow Research (AFR) 245 heads offer impressive flow numbers, registering 352 cfm at 0.650 lift. 55cc exh. These benefits provide more power and cooling, right out of the box. The 347 test motor was run with an Edelbrock Performer RPM intake and 750 Holley carb. By continuing to use our site, you agree to their use. These heads were formerly known as Pro-Topline. By continuing to use our site, you agree to their use. The head is equipped with 2.08/1.60-inch valves and despite the rather large intake valve, still creates over 100 cfm/sq.in. We flow them on a Superflow 600 flow bench at 28" of depression and use a 4.030 bore. with all the chatter about the new RHS heads i thought i would post numbers i got on their new 215 Ford alum. I'd love to see the two compared, so as to see at what point in lift, the 2.02 1.6 heads gained flow. RHS/IMM mopar head: 62-67cc Chambers available: 2.02 4 angle blended intake valve seat: Here is an example of how well these heads flow. © 2021 Racing Head Service. The flow numbers on the Ford Muscle test was on a 4.060 bore. We use cookies to provide you with the best possible user experience. They come available in both aluminum and cast iron and in a wide variety of intake runner and combustion chamber volumes. Remember that velocity produces low rpm torque, and flow produces high rpm horsepower. The lower the lift at which that number is reached, the better the port design. JavaScript seems to be disabled in your browser. If maximum flow is reached at.500" lift the head will produce a better power curve than if the valve must be opened to.700" lift or more to get the flow. Develped for high power Ford 302 - 351 Windsor street/track hydraulic roller applications. Add to this the change in displacement and compression and you have a motor just begging for more head flow. The INDY/RHS small blocks are available in both the LA style (La-X) and the Magnum style (Ma-X), and what follows are some points of interest that our customers may appreciate knowing about. If you just want to get an extra 20 or 30 horsepower out of your street vehicle, and you aren’t planning on performing 4000 RPM launches anytime soon, then that 170cc head is probably the best choice. with all the chatter about the new RHS heads i thought i would post numbers i got on their new 215 Ford alum. 2.08/1.60 RHS valve job on both Ferrea comp plus valves all numbers at 28"H2O 4.125 bore.100- 75 70.200- 132 112.300- 186 135.400- 234 178.500- 270 193.600- 285 195.700- 294 199 no pipe shawn 2.08/1.60 RHS valve job on both Ferrea comp plus valves all numbers at 28"H2O 4.125 bore.100- 75 70.200- 132 112.300- 186 135.400- 234 178.500- 270 193.600- 285 195.700- 294 199 no pipe shawn To learn more, view our. All rights reserved. RHS is the leading developer of high performance cylinder heads, engine blocks, intake manifolds and related components for street performance and race engines We use cookies to provide you with the best possible user experience. that are designed to work with them. Even so, the valve angle has been rolled 2° flatter toward the piston. At 3,900 rpm … (I asked a W/Products tech guy on this) RHS/IMM mopar head: 62-67cc Chambers available: 2.02 4 angle blended intake valve seat: Here is an example of how well these heads flow. To learn more, view our We use cookies to provide you with the best possible user experience. This is a large-port head at 220-cc and offers excellent intake flow numbers. We use cookies to provide you with the best possible user experience. Only the valve size is changed on them. All RHS® cylinder heads feature patented Clean Cast Technology™, a revolutionary process that eliminates casting flaws and promotes a smoother internal surface finish for greater air and coolant flow. Find RHS Pro Action Small Block Chevrolet Cylinder Heads and get Free Shipping on Orders Over $99 at Summit Racing! Most flow numbers for Scott Johnston heads … RHS shipped three Pro Action cylinder head castings to Westech in Southern California for us to demonstrate how these heads flow right out of the box. The RHS head uses a larger 2.02 inches of valve size to achieve these numbers, which instantly means that with equal flow numbers in the mid-lift areas that its velocity past the valve will be slower (but the pressure will be higher) compared to the stock 1.94-inch Vortec head. All RHS cylinder heads feature patented Clean Cast Technology, a revolutionary process that eliminates casting flaws and promotes a smoother internal surface finish for greater air and coolant flow. Not even W/Products seems to have numbers on their 1.94 1.5 76cc heads, except at .500 lift. Second in size only to the LS3 Mast heads, the … Flow bench testing and analysis of RHS Pro-Action cylinder heads for small block Fords. Pro Action cylinder heads by RHS deliver exceptional performance gains for all small block Chevy owners. Need help finding what you are looking for? Racing Head Service (RHS) 35025 - RHS Pro Elite Small Block Ford CNC-Ported Cylinder Heads Cylinder Head, Pro Elite, Aluminum, Bare, 62cc Chamber, 221cc Intake Runner, Ford, 289, 302, 351W, Each Part Number: RHS-35025 Feb 26, 2010. Bryan Neelan, engine builder at Late Model Engines shared this sentiment and added, “The RHS heads showed strong flow numbers with a nice port shape. Pro Action™ Cylinder Heads, the cornerstone of the RHS® line, are ideal for a variety of performance functions, including hot rods, drag racing, oval track racing and marine applications. This is a large-port head at 220-cc and offers excellent intake flow numbers. Compared to stock, the overall increase in cfm of the RHS heads might not be dramatic on a flow bench, but they still net a big increase in horsepower.” Dyno Test With the air/fuel dialed in to 12.7:1 and the ignition set to 28 degrees, the new RHS heads and custom COMP solid roller cam helped lay down 625 HP on SAM’s Dynojet chassis dyno. head. Six-head-bolt provisions come standard to match aftermarket blocks and provide extra clamping force. The flow figures delivered in test number-4 are more than enough to make a 12.5:1 350 small-block Chevy deliver in excess of 600 hp … Not even W/Products seems to have numbers on their 1.94 1.5 76cc heads, except at .500 lift. © 2021 Racing Head Service. Equipped with the Trick Flow 185 Street Port heads and the same Hooker long-tube headers, the Ford 347 Stroker produced 482 hp and 424 lb-ft of torque. HOW TO VIDEO: The truth about cylinder heads and flow numbers! Racing Head Service (RHS) 12044 - RHS Pro Action Small Block Chevrolet Cylinder Heads Cylinder Head, Pro Action, Aluminum, Bare, 72cc Chamber, 200cc Intake Runner, Chevy, 302, 327, 350, 400, Each Part Number: RHS-12044 That is why the Pro Elite heads are designed for stock-style valvetrain components. velocity numbers, with 112 at 0.200 inch lift particularly good. LS Aluminum Race Block (Ready to Hone) 9.250" Standard Deck - 4.120" Bore, Pro Action GM LS3 Rectangle Port Aluminum Cylinder Head - Assembled w/ .660" Lift Springs & Steel Retainers, Pro Action GM LS3 Rectangle Port Aluminum Cylinder Head - Bare, Pro Action Small Block Chevy Aluminum Cylinder Head (23° Valve Angle), Pro Action Small Block Ford Aluminum Cylinder Head (20° Valve Angle), Pro Action™ BBC 24° (320cc Intake Runner/119cc Chamber) Bare Aluminum Cylinder Head, Small Block Ford Cylinder Head Assembly Kit, 2.080"/1.600" Valves (Hydraulic Roller). These benefits provide more power and cooling, right out of the box. velocity numbers, with 112 at 0.200 inch lift particularly good. Thing that makes me laugh the most though, is that they keep saying they made the heads better, but the flow numbers are the exact flow numbers Pro Topline advertised lol. If I recall they flowed [email … I like the volume of the intake runner for the bigger cubic inches the RHS tall deck block accommodates. RHS designed these heads to flow big numbers without the need for crazy, exotic parts up top. Cookie Policy. The lower lift flow numbers are not as good as the CNC ported AFR 235 heads, but up at 700 lift, the reworked RHS is just as good as the CNC ported AFR. To learn more, view our. For the best experience on our site, be sure to turn on Javascript in your browser. Which is the correct way to go? Add to this the change in displacement and compression and you have a motor just begging for more head flow. The CNC porting includes not … Updated Aug. '12 — and were converted from 10" to 28". I'd love to see the two compared, so as to see at what point in lift, the 2.02 1.6 heads gained flow. For the best experience on our site, be sure to turn on Javascript in your browser. All rights reserved. (I asked a W/Products tech guy on this) Valve Sizes: 1.84" int. These Pro Action 215 cylinder heads are the perfect choice for big inch street rods, serious muscle cars, oval track and drag racing applications. For example: Lets take a head that flows a maximum of 300CFM. The S/R Heads and the S/R Torquers are exactly the same casting. The La-X head is the one we get the most calls on so we will show it and point out differences in the Ma-X heads … RHS designed these heads to flow big numbers without the need for crazy, exotic parts up top. For the best experience on our site, be sure to turn on Javascript in your browser. Cookie Policy. Given the tremendous flow potential of ported LS7 heads (some eclipsing 400 cfm), we needed more displacement. The La-X head is the one we get the most calls on so we will show it and point out differences in the Ma-X heads as they come up. By continuing to use our site, you agree to their use. The Edelbrock Performer RPM heads had excellent flow numbers, and they provided exceptional power and torque during our dyno testing. Racing Head Service Pro Elite LS7 Aluminum Cylinder Heads. The RHS Pro Elite LS7 cylinder heads are the aftermarket’s first high performance LSx style head to feature a raised intake runner design that fits both stock and aftermarket LS7 intake manifolds and valvetrain setups. The new Air Flow Research (AFR) 245 heads offer impressive flow numbers, registering 352 cfm at 0.650 lift. A tall-deck RHS aluminum block offered the capability to swallow a … Need help finding what you are looking for? JavaScript seems to be disabled in your browser. Only the valve size is changed on them. All flow numbers for RHS — Racing Head Service heads come from their Web Site updated Feb. '12. RHS is the leading developer of high performance cylinder heads, engine blocks, intake manifolds and related components for street performance and race engines GM LS3 - Cylinder Heads JavaScript seems to be disabled in your browser. Stock 351W (C9, D0, D8, D9 castings) Cost per pair: Varies Material: Iron Combustion Chamber Size: 60-69cc depending on year. The aluminum LS-series heads from RHS offer superior flow and power production thanks to precision CNC porting. To learn more, view our When it comes to deciding which cylinder heads to order, it is important that you make a realistic judgment of your intended use for your vehicle. The 347 test motor was run with an Edelbrock Performer RPM intake and 750 Holley carb. The tables listed below will offer some general cubic inch and RPM guidelines to consider when selecting the intake runner volume of your new cylinder heads: Small Block Cylinder Head Application Based On Intake Runner Volume*, Big Block Cylinder Head Application Based On Intake Runner Volume*. The S/R Heads and the S/R Torquers are exactly the same casting. Equipped with the Trick Flow 185 Street Port heads and the same Hooker long-tube headers, the Ford 347 Stroker produced 482 hp and 424 lb-ft of torque. For the best experience on our site, be sure to turn on Javascript in your browser. The INDY/RHS small blocks are available in both the LA style (La-X) and the Magnum style (Ma-X), and what follows are some points of interest that our customers may appreciate knowing about. As can be seen from the flow numbers in Figure 5.14 the EQ heads acquitted themselves very well. By continuing to use our site, you agree to their use.