The custom cams we selected all featured 0.624-inch lift (both intake and exhaust) and a 232/242-degree duration split. I would have to say that your cam choice sounds like a winner to me. 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! It may not display this or other websites correctly. For a better experience, please enable JavaScript in your browser before proceeding. I normally run a 106 to a 108 because I like the "hit" a tighter LC cam has when it come up on the came. That means your engine can produce more power with a minimum amount of fuel combustion. You get a better idle, vacuum, and response from a 112o-114o lobe. Well get out of that stocker and build a hipo motor for your VW. somthing to that aspect. It provides a spark plug with the high voltage needed for combustion. Like choosing a cam in general, the key to eliminating separation anxiety is to find the proper balance of driveability and performance. (ICL + ECL) / 2 = LOBE SEPARATION ANGLE (LSA) LSA is a RESULT of the PROPER events. i think a little more torque will be good for my car.With the XE274 it was a little slugish until around 3000 rpms. Like one cam is 112 degree and the next is 108 the 108 cam will allow less "leakage"? Split duration/lift only helps when your intake/exhaust ratio is low on the exhaust side. But, the narrow or broad powerband choice varies from person to person. This comparison highlights that the 106 LSA is a good performer in a few mechanical aspects than the 110 LSA. 1-4 It is one of the most common neurological disorders worldwide, 1-5 is among the most common . so it is a solid flat tappet, torker intake, 1" 4-hole tapered spacer and 750 carb (QFT) transmission is a wide ratio toploader, rear is a 9" 3.89 geared 26"rear tires. But nothing comes without a cost, and idle vacuum suffers as LSA shrinks. Brul spun the engine over with the dyno's starters and recorded 185 psi of cranking compression. Defining Lobe Center and It's Importance to Engine Performance: A Blog. A narrower LCA will increase valve overlap and close the (intake) valve earlier, which explains the typical rougher idler and more midrange behaviour. So, the 110 LSA engine is a suitable choice for people prone to be the fan of a powerful engine with mighty acceleration power. by mrsmythe Tue May 13, 2003 5:45 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.". When you purchase through links on our site, we may earn an affiliate commission, which supports our community. If the cylinder heads are the lungs of an engine, the camshaft is the brain. 02 The 402-inch stroker short-block combined an aluminum LS2 block with a 4.000-inch crank and 6.125-inch rods. 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. Higher overlapping lets less oil fall through the oil inlet. It affects the amount of valve overlap; that is the brief period of time when both the intake and exhaust valves are open. 110 LSA) and Crane's #341191 (238/248, .563"/.587", 114 LSA), display considerably different characteristics. Thanks again. Valve lift will bear weight in any decision regarding LSA. After consulting with many experts, you are still in confusion between 106 and 110- lobe separation angles. We use 86b webcams with 1.25 rockers frequently in stroker motors.It's a nice way of getting close to .500" for hot street motors with average heads. Enter lobe separation angle. But remember, although a broader powerband has a couple of acceleration advantages, it also comes with a few drawbacks. A wider lobe center will give you more overall torque (comes in earlier and stays later). Copyright 2022, S&S Motorsports LLC, All Rights Reserved - Powered by, http://www.webcamshafts.com/cam_glossary.html, http://www.newcovenant.com/speedcrafter haft/3.htm, Webcam 86A 108LC w/1.5 vs 86B 112LC w/1.3s. too much for the street? The 234o duration kind of eliminates the RV usage. 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. Well, there can be different reasons for this problem. It is the angle that separates the intake and exhaust lobe for a particular cylinder, and is measured in camshaft degrees. Kevko baffled oil pan & Milidon windage tray. Since we were only changing the lobe separation angle, we had to make sure every variable (air/fuel, timing, water, air, and oil temps) was identical during testing. However, the plentiful exhaust overlap (31 degrees) meant there was lots of exhaust dilution at low engine speed and high vacuum. I've heard similar cams (only about 5*'s off) and they have a nice rumble to them. Here are the basics: higher lift values open the valves to increase airflow and longer duration keeps the valves open longer. The article was called "Separation of Power" and they tested 5 cams ranged from 106 to 114 LSA. The LSA, or lobe separation angle, is ground into the cam and cannot be changed. It will sound lovely I'm sure. Coupled that with the low first gear of the five speed, it ought to create some real traction problems. " - Voltaire. More over-simplifications: The world of fuel injection is where wide LSA cams like the 113 really shine. The piston and cylinder damage possibility is pretty low at 110 LSA. 06 The ported heads featured a 2.165/1.590-inch valve combo. Tests 2 and 3 meant dissecting the motor on the dyno to get the old cam out. by MELWAY Sat Dec 06, 2008 4:18 pm, Post Save my name, email, and website in this browser for the next time I comment. A forum community dedicated to hot rod owners and enthusiasts. 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. The extra cubic inches will smooth out a rough idle in a 327. (2002) et rappel sur une carte hors texte. Compression willl be 9.75:1. 07 Though the CNC-ported heads offered plenty of flow, it was necessary to upgrade the supplied valvesprings. After spending 8 years in plant production engineering, Noah wanted to join Engine Addiction as a key member of all cars specific guides, reviews, repairs, suggestions, and more. by randy331 Sat Dec 06, 2008 10:00 pm, Post 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. by mrsmythe Wed May 14, 2003 2:26 am, Post A forum community dedicated to vintage Ford Mustang owners and enthusiasts. by Mr. P. Fri Dec 12, 2008 6:36 pm, Powered by phpBB Forum Software phpBB Limited, General engine tech -- Drag Racing to Circle Track. More than any other component, the cam profile determines things like idle quality, mileage, and overall driveability. [img]http://i67.photobucket.com/albums/h291/downsideup09/DSCF2616-1.jpg[/img], [img]http://photos-g.ak.fbcdn.net/hphotos-ak-snc1/hs139.snc1/5928_111214857139_110806152139_2127222_6826389_n.jpg[/img]. Unfortunately, good street manners are often at odds with performance, as wilder cam timing usually decreases idle and (low-speed) driveability. The 112-degree cam offered nearly all the low-speed and mid-range torque of the 108 cam but the peak power suffered above 5,200 rpm. 112 vs 114 lobe centers You cannot tell the differance in the two . This has been my long time understanding! Increased overlap improves upper RPM power. 108 Lobe Separation These are my motors specs 1979 - 347 Stroker 10:1 Compression Holley 670 Street Avenger or a Holley 650 (I have both) Roush 200 Cylinder Heads (minor head work) 1.6 Roller Rockers Shorty BBK Headers 373 Rear End 5 Speed Transmission Cross Gap Intake (Power Band 1500-6500) FlowMaster Dual Exhaust (of course no Cats) MSD 6Al My engine shop builds all kinds of hot rod motors, and they told me that because I am running a 4 speed manual, I will better be able to take advantage of the 108 LSA. The valve covers, valvetrain, intake manifold, harmonic balancer, front cover, timing set, and cam were yanked. With a 108 degree lobe center, a cam will have a rougher idle and produce less vacuum due to more overlap. Every spec is a road map to what the valves are doing, the most common of which are lift, duration, and lobe-separation angle (LSA)the latter needing the most explanation. See all 14 photos 13 The three power curves indicate that the wide (120-degree). 12 In terms of power production, the stroker LS3 performed best with the tightest lobe separation angle. 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. The lobe separation angle or LSA is the angle in camshaft degrees between the maximum lift points, or centerlines, of the intake and exhaust lobes. The balance of midrange torque and top-end horsepower lends this LSA range to the majority of street/strip engines. However it is at the expense of a small amount of bottom end power and idle quality, due to the increased overlap. Your best bet would be to talk to one of the experts at a cam company to get a custom grind if you're that into the specs. 13 The three power curves indicate that the wide (120-degree) LSA (green lines) lost considerable torque to the other two cams. 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. Is There a Sequence? Cylinder-head flow and LSA are directly related: as a rule of thumb, the better the head flows, the wider the LSA can be. Lobe Separation Angle "LSA "Jump to Latest Follow 1 - 17 of 17 Posts . How To Properly Replace Ignition CoilsContinue. It affects the amount of valve overlap; that is the brief period of time when both the intake and exhaust valves are open. The 110 is probably a better choice for a performance street engine. 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. Simply put, both 106 and 110 lobe separation angles have many advantages and disadvantages. = Moderately Wide 110-108 Deg. 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. A cam 112LSA with 4 degrees advance puts the intake centerline at 108 degrees. To further minimize any dyno variations, the engine's oil and water temperatures were kept the same for each pull. that is why people running 112 or 114 lobe centres retard the cam ,that way the exhaust event is back were it was before .this helps in exhaust valve tempatures--anyway today i talked too barry who is the owner of shadbolt cams and we talked about cam lobe centres -he considers 108 centre quite narrow and for a very narrow power band operation ,with a 112 he figures with the carbs with straight & even runs at the valves there should be no noticable loss of low end power, a 112 lobe would be a great choice for a great street strip motor -better lower torque followed with a flatter rising torque curve as well as rpm range extended 500-700 rpm -. Armed with more information on camshaft theory, what will you build? Pretty much standard for an RV type cam. BUT, 114 will have more vacuum at idle, which will work better with some fuelinjection. 110 LSA: On the contrary, if you look at the powerband at 110 LSA, the powerband is comparatively broader. Now that we have a basic understanding of lobe separation angle, we can put together a test to illustrate just what happens when you make changes to it. I had a 110 cam in my beetle and I didn't like it-the bottom end was doggy. Idle quality was rough and the vacuum gauge showed only 9.8 in-Hg (inches of mercury). How do the lobe separations change when you factor in turbocharging? 2.1.2.4.2 Side-lobe suppression shall be provided in accordance with the provisions of 3.1.2.1.5.2.1 on all Mode S-only all-call interrogations. But, at 106 LSA, the cranking compression may increase above the standard PSI level. from the intake to the exhaust and vise-versa.Thats why a performance cam will usually have a rougher idle than a stock one. A 110-degree lobe separation angle means that the peak opening points of the intake and exhaust lobes are 110 degrees apart. However, it is fixable. Pretty much standard for an RV type cam. 112-110 Deg. 106 LSA: 106LSA results in a decrease in piston-to-valve clearance. When you don't have any overlap, you can't have any wave tuning. dur. The 402-inch LS2/LS3 hybrid stroker started out with an LS2 aluminum block. Due to the tightness and frequent overlapping of the intake and exhaust valves, the engine cant generate the high RPM as it is supposed to. When you purchase through links on our site, we may earn an affiliate commission, which supports our community. This recommendation is only if you shift at no more than 7000. For large port heads like the CNC 044's which can use the extra lift 1.4's make a noticable difference. 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.. 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. 1-3 Cognitive impairment is common in both FLE and TLE and adversely impacts quality of life and psychosocial functioning. The lobe separation angle is a comprise of what the engine needs depending on the compression, combustion chamber, rpm, engine size, head volume, and many, many other variables. I also like the 106 lobe separation with the intake on 103. 110 LSA: On the contrary, 110LSA has a higher piston-to-valve clearance rate. 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. I bet you won't see a bit of difference. 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 . Check out the Comp Cams catalog, even the biggest hydraulic rollers use 110. Thanks. Lobe Separation Angle, or LSA, is the number of degrees that separate the peak lift points of the cam's intake and exhaust lobes. http://www.mustangworks.com/cgi-bin/moi-display.cgi?220, http://www.popularhotrodding.com/en6em_camshaft_specs/lobe_seperation_angle.html. Wide LSA cams are also applicable in forced-induction applications where less exhaust overlap is required. Once more the engine came apart to install the third test cam, a 107 LSA. At a lower LSA, the engine reaches the peak of the torque earlier than the standard time but generates a lower RPM.On the contrary, at a higher LSA, the engine reaches the peak torque at a higher resistance level and generates a bulk number of RPM. Well, If I am not mistaken, you must be looking for which angle has what impact on your engine or which would be the best. 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 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. So, choose the perfect lobe separation angle for your engine, complying with the requirements of your needs. 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. 2.1.3 Transponder reply modes (air-to-ground) 2.1.3.1 Transponders shall respond to Mode A interrogations in accordance with the provisions of 3.1.1.7.12.1 and to Mode C interrogations in accordance . A 112 LSA would be better if I had an automatic, but the engine builder (who has built many, many drag racing engines)told me I would have much faster acceleration with the 108, at the expense of a broader power band of course, but that 108 would not unduly penalize me for the street. What brand and what are the specs on your cam, 4-linked72? It's the scavenging effect of the high velocity exhaust gases rushing out that pulls the fresh fuel/air charge into the chamber. Lower cylinder pressure is advantageous for your engine. 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. But for small-block Chevys (like the LS applications in this story), the LSA is ground into the cam. Cam swaps are all the rage and for good reason. Another difference between the two involves the power curve. = Extremely Tight . As usual, Marc (aka Master) is correct. Most cars use more than, Read More Does It Matter Which Ignition Coil Goes Where? The exhaust has an opening even and a closing event. The Fora platform includes forum software by XenForo. 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: Oppositely, the cylinder pressure is comparatively lower at 110 LSA than at 106 LSA. by xstfudonniex Sat Dec 06, 2008 4:21 pm, Post Is it a hydraulic roller as well? In general, a stock replacement camshaft with duration of less than 200 degrees will have a lobe separation angle of more than 114 degrees. Generally speaking, decreasing the lobe centerline angle increases overlap. 110 LSA: But, contrarily, at 110 LSA, you dont have to face the problem of engine knocking. 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. GRIND #: CRB3 3194 /3196 HR111. The final, 108-degree cam stepped power up even further, with peaks of 572 hp at 6,300 rpm and 544 lb-ft at 5,200 rpm. The only reason the advance or retard a camshaft profile is to get the timing events where they need to be. 68 Mustang, 306, AFR 185\'s, CI cam, FPA\'s, Bigs 650 DP, T5Z, 9" w/4.33's. Pontiac 326 Vs Chevy 327 Differences & Similarities. As lobe seperation spreads does the powerband. A wide LSA reduces valve overlap, softens the idle and improves overall drivabilityespecially on the street where performance engines benefit from 112 to 114 LSA. A cams Lobe center angle equals intake centerline plus exhaust . LSA CAM TEST-108 vs 112 vs 120 Richard Holdener 239K subscribers 168K views 2 years ago WESTECH PERFORMANCE GROUP FULL RESULTS-CHANGE ONLY LSA-LS CAM TEST. The #1 intake lobe centerline is usually between 100 document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); Disclaimer: Remember to always consult with an expert first before trying anything at home. Brul slid the 113-LSA cam, the widest of the test, into the engine's heart and set about putting all the pieces back in place. Contrariwise, 106 LSA car engines are the best choice for people seeking energy-efficient cars with moderate engine power. But, you may wonder knowing that a higher valve clearance rate reduces the chance of damaging the valve by the piston. Again this is dependent on your shift rpm and assuming you truly have 14-1 compression. 106 LSA: You can see an increasing EGR effect at 106 LSA. On a torque graph it tends to resemble a triangular shape.. you cannot just take a random change in a lobe separation angle and say 1 is better than the other. True enough, the tight LSA improved power through the entire rev range, from 3,600 to 6,500 rpm, but the extra power came with a penalty in idle quality. LSA is a way of summing up the relative timing of the intake-valve events (intake opening, intake closing) to the exhaust-valve events (exhaust opening, exhaust closing) in relation to each other, and it's a great approximation of how the engine will operate. Well, I saw that Erson makes some nice hydraulic rollers with 108 LSAs, and I know that tighter LSAs have more midrange, so I thought they might be worth a try. Hopefully It will do fine in my 2276 mostly drag bug. The tightest LSA (101) was worth 21.5 lb-ft of torque and a much broader powerbandat the cost of much lower idle vacuum, which would make it more temperamental in a street car.