108 vs 110 lobe separation

We'll send you raw engine tech articles, news, features, and videos every week from EngineLabs. Anybody do any real testing on LSA in a 3.75 stroke small block chevy?I have always used 104-106 and was thinking about trying a 108 or 110 design.I know there is a lot of variables but just a general opinion from any experts.This is for motor only no nitrous.600-640 HP engine combos.Much appreciated! For a better experience, please enable JavaScript in your browser before proceeding. 110 vs. 112 lobe seperarion on a cam - Chevy Message Forum 1966 Toyota Landcruiserunder construction. 11 Doing LS cam swaps on the engine dyno is a breeze, each taking less than 1 hour. The Idles increasing vacuum improves the idle quality and the engines overall performance. Consequently, decreased torque rate often leads to more energy consumption. = Moderate 108-106 Deg. Boom, you get the lobe separation angle of that engine. A commonly held misconception is that intake/exhaust overlap contributes to lower cranking compression. LSA helps determine the cam's behavior; you can take a given set of lift and duration figures, change the LSA, and get cams with vastly different characteristics. Tight lobe separations, such as 108 or shorter, will cause the peak torque to build earlier in the RPM range and peak-out in a short amount of . 114 vs 110 lobe sep. on cam | NastyZ28.com But i would nt go any wider than 110. Thanks. This is why the LS series, and many other modern engines, can make great power on top and bottom with wide LSA camshafts and why a plethora of factory cylinder heads are flowing near (or above) 300 cfm. Tests 2 and 3 meant dissecting the motor on the dyno to get the old cam out. The tighter the lobe separation angle, the peakier the power curve will be, confirms Bolander. I know a little about cams. I also like the 106 lobe separation with the intake on 103. A forum community dedicated to Ford performance owners and enthusiasts. This recommendation is only if you shift at no more than 7000. The only reason I . It provides a spark plug with the high voltage needed for combustion. Camshaft Kits - 108 Lobe Separation (degrees) - Summit Racing It is dangerous to be right in matters on which the established authorities are wrong. Despite no changes in lift or duration, this cam sounded much more aggressive than the other two with wider LSAs. As boost increases, the air will be forced through the cylinder, vs. being trapped in the cylinder. The introduction of Lunati'snew Bootleggerhydraulic series - with its wicked 108-degree lobe-separation angle, fast opening profile and plenty of area under the lift curve - will serve only to fuel the flames on this heated bench-racing topic. A wider lobe separation angle can often provide more power, but it can also lead to more wear on the engine. This comparison highlights that the 106 LSA is a good performer in a few mechanical aspects than the 110 LSA. An icon used to represent a menu that can be toggled by interacting with this icon. Aluminum flywheel & pullies. Simply put, both 106 and 110 lobe separation angles have many advantages and disadvantages. That was all, and we have already reached the concluding point. On larger displacement units 116 to 118 degrees of separation are common. 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Elle concerne 264 taxons des degrs divers. by Kdub Sat Dec 06, 2008 11:05 pm, Post THis is a real generalization, but the weaker your heads, the more you will like the smaller centers ( 106-108) the better the heads, and the higher the compression, the more it will like the wider centers ( 112-114)everything else falls somewhere in the middle( 108-110) Once you get close with the cam centerlines, it wont make much differance if you change it up or down by 2 degrees. Post What brand and what are the specs on your cam, 4-linked72? Camshafts Demystified - CarTechBooks This is one of the many reasons why Clay Smith Cams always recommends degreeing your camshaft in using the Lobe Center Method. If a street car has smaller lift and duration numbers, they might run 112 or 114. Lobe seperation cant be seperated from duration,the 2 are connected.the old duntov cam had a lot less duration than many new cams so the valve overlap was not extreme and the engine ran with a gentle lope.Increase the duration by 20* and this cam would shake a 283 out of the car at idle,but then increase the lobe seperation by 4* and the motor will have a gentle lope again. Some of the confusion on this subject comes from what the meaning of "bottom" and "top" is to the speaker, I suppose. I'm sorry to disagree with that incredibly well written article, but lobe separation by itself is absolutely freaking meaningless. With a 108 degree lobe center, a cam will have a rougher idle and produce less vacuum due to more overlap. Everyone has a different idea of gentle.While its true that the duntov cam may seem rough in a 283 it is still a factory offering and they never go to radical on there profiles for street cars.If you want a rough idle, try a 283 with a .550'lift roller and 13.5 to 1 compression,THATS ROUGH. I forgot to add that poor vacuum is not much of a concern to me because I have no power accessories. Its also critical that valve overlap is kept to a minimum as the induction system can create a suction that pulls water into the motor, adds Bolander. This may be of concern if you have vacuum assisted accessories, such as power brakes or steering. Higher overlapping lets less oil fall through the oil inlet. Unfortunately, good street manners are often at odds with performance, as wilder cam timing usually decreases idle and (low-speed) driveability. We borrowed Westech Performance's shop mule, a 370ci small-block Chevy and its SuperFlow 902 engine dyno and spent a day running each cam back-to-back to gauge its effect on peak horsepower, peak torque, cranking compression, idle vacuum, and the powerband as a wholeall the variables that define an engine's character on the street and track. in some cases,, the average torque can equal out. This cam split the difference between the 101 and 113 down the middle, and in theory should have walked the line between the results of the last two tests in every waywhich it did. i have a 4 bolt 351C, stock bore, 10.5 cr with 351C Boss heads ,boss crank and rods. 106 LSA: At 106 LSA, the cylinder pressure is a bit higher. If you want a lumper idle go with a cam with 108 LSA, the tigher the LSA the idle will be rougher. The other thing is that you need to tune your ignition advance to maximize your performance. The 112-degree cam produced peak numbers of 567 hp at 6,200 rpm and 540 lb-ft of torque while pumping out 511 lb-ft of torque at 4,000 rpm. Cam and Lifters, Hydraulic Roller Tappet, Advertised Duration 282/288, Lift .589/.600, Chevy, Big Block, Kit. Part Number: HRS-CL120325-08. On the cranking. Lobe Separation Angle Explained and How it Affects Horsepower - MotorTrend Alternatively, if you are running a bigger camshaft to gain maximum top-end power, cam makers often suggest reducing the lobe separation angle to recover power lost in the lower rev range.. For any additional clarification or questions please contact our Tech Line at 714 523-0530. https://www.youtube.com/watch?v=57gfBu8uc6k&t=1s. We do not stock profiles with 109 or 114 lobe centers. Professionally ported & polished iron 4V head with titanium intake valves, stainless exhaust, titanium retainers & keepers & dual springs. That was just a glimpse of the information you were looking for. It a 355. thanks in advance. So, this LSA is suitable for your engine and its components. 112 will have a smoother idle, a wider power band, and will work better with fuel injection. 07 Though the CNC-ported heads offered plenty of flow, it was necessary to upgrade the supplied valvesprings. Pinning the tail on the perfect cam can certainly be a difficult task. L'auteur prsente une nouvelle contribution de floristique nord-africaine consacre la flore du massif du Rif et des rgions du nord du Maroc, dans le cadre gographique prdfini par le Catalogue des Plantes vasculaires du Nord du Maroc de Valds et al. 12 In terms of power production, the stroker LS3 performed best with the tightest lobe separation angle. I'm surprized at these questions as well as some of the replies. " Topping the short-block was a set of Chevrolet Performance CNC LS3 heads from Gandrud Chevrolet. probably just enough to get me in trouble.. Generally, naturally aspirated engines run narrower lobe separation angles of around 106 to 108 whereas supercharged, turbo or nitrous engines operate with 112 to 114 and higher. 1-3 Cognitive impairment is common in both FLE and TLE and adversely impacts quality of life and psychosocial functioning. by SStrokerAce Sun Dec 07, 2008 12:22 am, Post According to the Comp Cams catalog, "The lobe separation angle (LSA) is equal to 1/2 the angle in crankshaft degrees of rotation between the maximum exhaust valve lift and maximum intake lift.". A forum community dedicated to hot rod owners and enthusiasts. (ICL + ECL) / 2 = LOBE SEPARATION ANGLE (LSA) LSA is a RESULT of the PROPER events. And better gas mileage. It affects the amount of valve overlap; that is the brief period of time when both the intake and exhaust valves are open. All rights reserved. CAMSHAFT guys, explain lobe centers to me | The H.A.M.B. I probably would have gone with 3.55 gears had I knows better.. Well, there can be different reasons for this problem. Whatever you do, stay under 270 advertised duration and shoot for a 110 lobe separation. The 108-degree cam (blue lines) outperformed the other two, but idle quality suffered. The Crane has a smoother idle, broader power band, and . VerticalScope Inc., 111 Peter Street, Suite 600, Toronto, Ontario, M5V 2H1, Canada. 106 LSA: 106LSA results in a decrease in piston-to-valve clearance. Mike Magda is a veteran automotive writer with credits in publications such as Racecar Engineering, Hot Rod, Engine Technology International, Motor Trend, Automobile, Automotive Testing Technology and Professional Motorsport World. Well get out of that stocker and build a hipo motor for your VW. by flat4racer17 Mon May 12, 2003 1:40 pm, Post Either learn to fix it, or learn to write checks. Powerband serves a massive contribution to the acceleration car. (You can find an instructional video of how to do just that on our Clay Smith Cams YouTube Channel;https://www.youtube.com/watch?v=57gfBu8uc6k&t=1s ). I do believe that stock VW seperation is 108 and 112 is used alot in turbo and midrange cams for VW's while 106 is used for the top end cams. While most of our customers know what lift and duration are, most are unfamiliar with the term Lobe Center and how it affects the engines performance. Known as "The Gladiator" around Westech Performance, this Dart SHP blockbased, 370ci, small-block Chevy has made thousands of dyno pulls testing all manner of heads, intakes, cams, and every other crazy thing us magazine folk have coerced Westech's Steve Brul to bolt to it. i've heard of this being done something about the massive amounts of duration allowes gasses to disipate? The 114 cam will give more low end torque, good midrange, less power up high. A lower efficient compression rate leads to a higher fuel consumption rate by your engine to produce higher power. The higher the compression and the higher you try and rev it, the more it will like a wider lobe center. If you drew a line that divided the intake lobe in half right at the point of maximum lift, then did the same to the exhaust lobe, then measured the distance in cam degrees between the two, that would be the lobe separation angle. by Hoxviii Mon May 12, 2003 7:50 pm, Post Save Share. Some prefer a narrow powerband, and some prefer the broader one. Thanks for the replies, particularly that link Marc, very informative. i think a little more torque will be good for my car.With the XE274 it was a little slugish until around 3000 rpms. Looking at 108vs. too much for the street? Test 1 was easy. Good cam for a lower rpm street engine. A cam with a 112 lobe center will pull approximately 16-20" of vacuum, which is good for power brakes. My duration will be about 230 degrees. A good amount of idle vacuum or increased idle vacuum found at 110 LSA advances the engines efficiency. When choosing a cam, power gains shouldn't be the only consideration. by mrsmythe Wed May 14, 2003 2:26 am, Post How to Choose a Camshaft for Street Vehicles - OnAllCylinders A cam's lobe separation determines where and for how long peak torque occurs in an engine's rpm range. For your convenience, I am providing a comparison table to give you an overall idea about the comparison. Typically, narrower lobe separation develops peak torque at lower rpm and widening the separation tends to build peak torque higher in the rpm range. A cam 112LSA with 4 degrees advance puts the intake centerline at 108 degrees. It had a robust powerband with tons of usable torque. It affects the amount of valve overlap; that is the brief period of time when both the intake and exhaust valves are open.. I am trying to pick out a hydraulic roller cam for my 351W with AFR 185s. *If you do not have enough vacuum, you can in some cases install a vacuum canister or reservoir, which works by storing the peak vacuum in the reservoir. Turbochargers are not as simple as they may sound; you may think of them only as power-boosting components. Higher lift and longer duration profiles add power, but do so at higher engine speeds (especially true of duration). The 290 advertised duration and 114 lobe separation would contribute to a lazy power curve. Lunati's New Bootlegger Camshaft Series Has Strong Race - Dragzine The valve covers, valvetrain, intake manifold, harmonic balancer, front cover, timing set, and cam were yanked. To further minimize any dyno variations, the engine's oil and water temperatures were kept the same for each pull. Lobe Separation Angle, or LSA, is the number of degrees that separate the peak lift points of the cam's intake and exhaust lobes. While lift and duration are most often discussed when talk turns to cam timing, there is a third variable that has a decided effect on both power and personality. Now its not shifting into 3rd and you are here. Howards Cam Vs Comp Cam: Which Is The Best Option For You? Pontiac 326 Vs Chevy 327 Differences & Similarities. 06 The ported heads featured a 2.165/1.590-inch valve combo. But to choose the perfect cam, all of that information needs understanding. The only reason the advance or retard a camshaft profile is to get the timing events where they need to be. The engine would idle a lot rougher and generate worse exhaust emissions largely because of unburned fuel.. As a result, you can enjoy a pleasing engine outcome. 106 Vs 110 Lobe Separation Angle: Real Impacts You Must Learn Introduction. how much boost on a 110 lob sep cam vs 112 vs 114 Cam swaps are all the rage and for good reason. Cylinder-head flow and LSA are directly related: as a rule of thumb, the better the head flows, the wider the LSA can be. Ed JTO learn to park Joined May 31, 2009 180 Posts It also depends on what the vehicle will be used for and if economy and vacuum are important. I'd run it, just be sure to check valve to piston clearance, coil bind and retainer to guide boss/seal clearance. Need some Cam Advice! | Chevy Tri Five Forum The other thing is that you can make more power with a smaller aftermarket cam. Lobe separation angle does. Lobe separations on 383-406 cids.104-106-108-110? . The LSA, or lobe separation angle, is ground into the cam and cannot be changed. On a naturally aspirated engine, the lobe separation angle has an effect on whether the engine reaches peak torque a little earlier or later in the rpm range. But, after comparing these two LSA based on a few mechanical aspects, such as maximum Torque, RPM, powerband, oil consumption, and many more, you will find the 106 LSA with better performance output. But, at 106 LSA, the cranking compression may increase above the standard PSI level. 4-Link72, do you run racing gas or pump with 10.5:1 CR? Similarly, 110 LSA is also found to be a more fabulous performer in several mechanical aspects. A cams Lobe center angle equals intake centerline plus exhaust . The 108-degree cam offered both the most power and torque, but idle quality suffered compared to the wider LSAs. I though my car would have a nice rough idle with the solid cam with a tight LSA I put in my car, its go a slight lope to it, but it pulls hard. Equipped with the 120-degree (LSA) cam, the hybrid stroker produced 570 hp at 6,200 rpm and 535 lb-ft of torque at 5,200 rpm. by Marc Mon May 12, 2003 11:38 am, Post Engine knocking generally occurs when the burning of the fuel by the engine is uneven. 114LSA +4 puts the intake centerline at 110 degrees before top dead center. 238/248 duration, 300/310 adv. 106 lobe sep. in a street car. | NastyZ28.com You get a better idle, vacuum, and response from a 112o-114o lobe. Before we all start suffering from separation anxiety, we need to understand what lobe separation angle actually is and then how it affects your engine. Lobe Separation Angle - Restoration and Repair Help LSA is a result of valve timing events. 110 LSA: Oppositely, the cylinder pressure is comparatively lower at 110 LSA than at 106 LSA. 106 LSA: There is an increasing chance of engine knock at the 106 lobe separation angle. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); Disclaimer: Remember to always consult with an expert first before trying anything at home. Lobe separations gives lots of overlap and lobe centers just happens when the grinder decides how the peak of the lobe will arrive on a specific grind by their tooling. I've seen a few comments in threads on here that have said things like "going to the 112LC from the 108LC gives 4lbft more torque at the bottom and 2bhp more at the top" yet this would seem to go against what webcam say on. Simply put, the lobe center of the camshaft controls where the power curve is applied. Effect Of Changes In Cam Timing And Lobe Separation Angle - COMP Cams Build your own custom newsletter with the content you love from EngineLabs, directly to your inbox, absolutely FREE! I think that cam had 110 lobe sep. Im loking at a summit cam with close to the same lift and duration #s but 114 lobe sep. Noah knows a lot about whats happening in the car industry with the latest piloting productions thanks to his professional experience. A forum community dedicated to vintage Ford Mustang owners and enthusiasts. But nothing comes without a cost, and idle vacuum suffers as LSA shrinks. However, the plentiful exhaust overlap (31 degrees) meant there was lots of exhaust dilution at low engine speed and high vacuum. by ANT Tue May 13, 2003 1:08 pm, Post Contributions la connaissance de la flore du Maroc et de l'Afrique du Another difference between the two involves the power curve. 108 is very tight producing lower vacuum and more of a 2 stroke "punch" powerband. by xstfudonniex Sat Dec 06, 2008 4:21 pm, Post The 30-30 Duntov is on the high end of the duration recommendation. not exactly true, Ive seen custom grinds that are on 108 lca, smooth idle, high vacuum an even able to run efi, usually on an off the shelf cam it is true. Once more the engine came apart to install the third test cam, a 107 LSA. 110* LSA - lobe separation angle (lobe displacement angle) The +2* means your intake lobe centerline is advanced to obtain a 108* ICL - intake centerline and a 112* ECL - exhaust centerline. Required fields are marked *. If you look at any given cam catalog, you will find that the majority of street-oriented cams fall in this range. What real difference does the lsa on a cam make? A narrower LCA will increase valve overlap and close the (intake) valve earlier, which explains the typical rougher idler and more midrange behaviour. However it is at the expense of a small amount of bottom end power and idle quality, due to the increased overlap. A 112-114 degree lobe center will have a better idle and produce more vacuum with less overlap. Widening their separation angle helps increase upper rpm power output. The intake air control valve (IAC), which regulates idle speed, also has to work overtime and often attempts to "catch" the idle, but usually shoots high or low. So, you can enjoy a mighty acceleration power at 110 LSA. On a torque graph it tends to resemble a triangular shape.. I've seen a few comments in threads on here that have said things like "going to the 112LC from the 108LC gives 4lbft more torque at the bottom and 2bhp more at the top" yet this would seem to go against what webcam say on. So, without wasting any moment, lets find out the answer. Comparison Table Between 106 Vs 110 Lobe Separation Angle. That is no accident. On a tight lobe separation, like 106-108 degrees, the engine will build torque quickly and reach its peak early. TH400 Vs Powerglide: Which One is Ideal for You? It has been tried in the VW business earlier, but then they gave it up because of problems with too high temperatures around the exhaust valve, causing them them to break. This is ground into the cam and can't be changed without changing cams. 106 LSA: So, if I talk about the powerband at 106 LSA, the powerband is narrow. When you don't have any overlap, you can't have any wave tuning. Lucky for us, Brian Tooley Racing stepped up with a dual spring package that allowed us to safely run our 0.624-lift cam. 04 Minor modifications to the factory windage tray were necessary to work with the new stroker assembly. In general, a stock replacement camshaft with duration of less than 200 degrees will have a lobe separation angle of more than 114 degrees. It is the angle that separates the intake and exhaust lobe for a particular cylinder, and is measured in camshaft degrees. 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If you shift at 7500-7800 add 4-6 degrees to both intake and exhaust and spread the lobe separation to 108-110. 110 LSA: However, if you look at the rate of cranking compression at 110 LSA, you will find a reduced compression rate from the standard cranking compression PSI level. But this is not the only reason. They also reduce stress on the outdrive. 08 Additional components used to build the stroker included a set of Comp hydraulic roller lifters, ARP head studs, and a new oil pump. Thanks again. If you compared these two cams side by side in identical engines, the first cam would actually have a slightly better idle and would produce slightly more peak power at upper RPM's. A 232 deg duration cam with a 108 deg LCA will have the same valve overlap as a 236 deg cam with a 110 deg LCA and idle will probably be very similar. 106 LSA: At this LSA, the car machine has to confront the reduction of idle vacuum rate quite often. " - Voltaire. Camshaft Shootout: Lobe-Separation Angle Tested and Explained - MotorTrend I don't know about 13 to one but I have seen 12 to one on a 350 chev in hot rod article, BUT the guy soft petals around on the street with no full throttle use and puts racing gas in at the track. He also enjoys reading books a lot and his favorite author is Paula Coelho. It made 472.4 lb-ft at peak, a 21.5lb-ft disparity from the 101 cam. These favorable mechanical features depict the powerful acceleration capacity of the engine with higher oil and energy consumption rate, overheating problems, and other mechanical problems. BUT, 114 will have more vacuum at idle, which will work better with some fuelinjection. LSA CAM TEST-108 vs 112 vs 120 - YouTube It will have slightly higher vacuum at idle, feel smoother through the power curve but have a bit less midrange. The takeaway is simple on the surface: A tighter LSA makes more low-end and peak torque at the expense of just a few top-end ponies. LS Exhaust Manifold Bolt Torque (Everything You Need To Know), Holley Power Valve Sizes: Everything There is to Know. If the exhaust valve closes too early it will trap some of the spent gases in the combustion chamber, and if it closes too late it will over-scavenge the chamber and take out too much of the charge, again creating an artificially lean condition. 110 LSA: On the other hand, 110 LSA is comparatively a wider LSA; it can generate a massive amount of RPM for the engine. by ANT Mon May 12, 2003 1:47 pm, Post Kevko baffled oil pan & Milidon windage tray. The article was called "Separation of Power" and they tested 5 cams ranged from 106 to 114 LSA. When degreeing in the camshaft, you are making sure the intake centerline is precisely where the cam is intended to be. This form of short-term memory is supported by the prefrontal cortex (PFC) and is believed to rely on the ability of selectively tuned pyramidal neuron networks to persist in firing even after a to-be-remembered stimulus is removed from the environment. If that accessory still does not assist the cam in producing enough vacuum, then as a last resort you can use a vacuum pump. But you always have a cam card with the engine. Good cam for a lower rpm street engine. The 402 was run with a FAST LSXR LS3 intake and matching 102mm throttle body along with stock LS3 rockers, a Holley HP management system and 7.4-inch hardened pushrods (from Comp Cams). This causes the engine's street manners and tuning to become fickle. you cannot just take a random change in a lobe separation angle and say 1 is better than the other. The first cam featured a wide 120-degree LSA, while cam number two narrowed the angle to 112 degrees. such as 290 @.050? I think you are asking a lot of a cam . A cam with a 112lobe center will idle smoother than a cam with a 110lobe center. Usually, this separation angle ranges from 95-degree to 120-degree. I just installed a Comp Cams XE262 in a 9:1 350 with stock iron heads. 110 LSA: The 110 LSA shows up mechanically advantageous in mechanical aspects like higher RPM, lower engine knock, moderate cylinder pressure, improved idle vacuum, and higher piston-to-valve clearance.