How to Choose a Camshaft for Street Vehicles - OnAllCylinders Camshaft Shootout: Lobe-Separation Angle Tested and Explained - MotorTrend 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. 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! The 108-degree cam offered both the most power and torque, but idle quality suffered compared to the wider LSAs. To illustrate the differences offered by changes in the LSA, we had Crane cams grind us three cam profiles that shared the same lift and duration figures, but differed only in the LSA. 106 LSA: There is a scale of standard cranking compression of the engine. by mrsmythe Wed May 14, 2003 2:26 am, Post Bad idea in my view. by ANT Tue May 13, 2003 1:08 pm, Post cam for torque.110 or 112 LSA????? - Team Camaro Tech Come join the discussion about restoration, modifications, NOS parts, troubleshooting, VIN codes, and more! Compression willl be 9.75:1. Simply put, the lobe center of the camshaft controls where the power curve is applied. It is the average centerline between both lobes and expressed in degrees ranging from 95 on the extremely narrow/tight side to upward of 120 on the wide end. On the cranking compression test, Brul recorded 175 psi, a 10-psi drop from the outgoing 101 cam. 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. Effect Of Changes In Cam Timing And Lobe Separation Angle - COMP Cams Lobe Separation Angle. - 332-428 Ford FE Engine Forum A 112-114 degree lobe center will have a better idle and produce more vacuum with less overlap. A wider lobe center will give you more overall torque (comes in earlier and stays later). 110 LSA: On the contrary, it is pretty unpleasant to inform you that the efficient compression rate decreases at 110 LSA. Check out the Comp Cams catalog, even the biggest hydraulic rollers use 110. 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. Has anybody experienced it/ tried it? But for small-block Chevys (like the LS applications in this story), the LSA is ground into the cam. The second cam would have a rougher idle, produce more torque and would rev quicker. A mobile functional near-infrared spectroscopy (fNIRS) was used to record cerebral oxygenation signals in the left prefrontal cortex (LPFC), right prefrontal cortex (RPFC), left parietal lobe (LPL), and right parietal lobe (RPL) and analyze the EC of the cerebral cortex. But an interestingly shocking fact is that this event escalates the air-fuel mixtures reaction rates, causing temperatures to rise and causing the problem of overheating the engine. Another related thought to consider when selecting a cam is inches of vacuum for your engine application when deciding upon a Lobe Center. Again, these are general bits of conventional wisdom. Usually, this separation angle ranges from 95-degree to 120-degree. If identical and for a given displacement the 110 will give more power. Thats just the way the customer wants to roll, and engine builders find its easy to deliver such a powerplant. A forum community dedicated to hot rod owners and enthusiasts. 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. The #1 intake lobe centerline is usually between 100 The 110 is probably a better choice for a performance street engine. I have Crane hydraulic link bar style roller lifters, so I dont have to use the spider style. Consequently, decreased torque rate often leads to more energy consumption. 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. 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. NOTE: Classic Inlines stocks the above profiles in 108, 110, and 112 lobe centers. In this segment, I am going to compare those two lobe separation angles based on a couple of mechanical factors. by 3V Performance Sat Dec 06, 2008 4:38 pm, Post Armed with more information on camshaft theory, what will you build? But, you may find a lobe wider than a 120-degree angle in any car engine.But, I must let you know that those are customized car engines prepared for any special purpose, such as racing, drag racing, off-road riding, or performing stunts. The absence of engine knocking ensures that your car engine is reasonably combusting the fuel. 10 Tuning the timing curve and fuel from the 42-lb/hr FAST injectors was handled by this Holley HP management system. 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. Lobe sepsration is an advanced description for overlap.If you take a cam on a 112,and grind it on a 108,you add more overlap,the time the valves are both open.Narrower lobe centers mean more low end and midrange torque,along with a peakier powerband,and a slightly rougher idle.Tradeoffs are sensitivity to octane ratings,total timing, and air fuel ratio.A lot to swallow I know,hope this helps you. Lobe separations on 383-406 cids.104-106-108-110? On a torque graph it tends to resemble a triangular shape.. LCA (lobe center angle) vs LSA (lobe seperation angle) So, you can enjoy a mighty acceleration power at 110 LSA. However, it is fixable. Noah knows a lot about whats happening in the car industry with the latest piloting productions thanks to his professional experience. Higher overlapping lets less oil fall through the oil inlet. 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. . 110 LSA: But, contrarily, at 110 LSA, you dont have to face the problem of engine knocking. One segment that truly benefits from a wider LSA is the marine marine market. Chuck Lawrence of Jon Kaase Racing Engines was asked to give a 520ci BBF a Pro Stock sound, so he went with a 108 LSA in place of a more conventional 112 LSA. by Marc Mon May 12, 2003 11:38 am, Post Frankly cams with a 108-114 lca unless in the perfect combo you won't usually see more than 15hp and you won't really feel the difference except for either a peaky or broad power band. i think a little more torque will be good for my car.With the XE274 it was a little slugish until around 3000 rpms. It affects the amount of valve overlap; that is the brief period of time when both the intake and exhaust valves are open. by bigjoe1 Sat Dec 06, 2008 10:48 pm, Post For a better experience, please enable JavaScript in your browser before proceeding. The lumpy-idling 101 LSA cam churned out an average of 484.0 hp at 6,100 rpm with 493.9 lb-ft of torque at 4,400 rpm. The 402-inch LS2/LS3 hybrid stroker started out with an LS2 aluminum block. Around 70 percent of muscle-car performance cams fall into this range. The higher the compression and the higher you try and rev it, the more it will like a wider lobe center. 108 vs 112 LSA | Team Camaro Tech For large port heads like the CNC 044's which can use the extra lift 1.4's make a noticable difference. But remember, although a broader powerband has a couple of acceleration advantages, it also comes with a few drawbacks. by bug1914 Tue May 13, 2003 2:56 am, Post Thanks for the replies, particularly that link Marc, very informative. Things like idle vacuum, fuel economy, and tuning all factor into picking the right cam. Camshaft Lobe Separation Angle | Classic Car Restoration Club As lobe seperation spreads does the powerband. A 110-degree lobe separation angle means that the peak opening points of the intake and exhaust lobes are 110 degrees apart. (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 ). 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. OK, what is hydraboost, and how do you like how the cam performs??? If two cams are identical with the exception of lobe separation angle (we'll say 108 and 114) the cam with 114LSA will make more low end power than the 108LSA cam? For a better experience, please enable JavaScript in your browser before proceeding. The 290 advertised duration and 114 lobe separation would contribute to a lazy power curve. Higher lift and longer duration profiles add power, but do so at higher engine speeds (especially true of duration). If that were the only consideration, the 101 cam is the clear winner. These numbers can vary a few inches one way or the other, depending on several other aftermarket factors and your individual engine specifications, so you may want to check your vacuum once the cam is installed. The power and torque curve lay directly in between the last two cams, as did the peak horsepower and torque, 488.7 at 6,200 rpm and 487.1 at 4,600 rpm, respectively. To overcome this inherent problem in wide LSA camshafts, you simply need a higher-flowing intake port. Camshafts with a substantial overlapping tendency should not be used in vehicles driven on public streets. 106 LSA: The overlapping is higher as 106 LSA is comparatively tighter LSA than 110 LSA. to use this representational knowledge to guide current and future action. 106 LSA: As you know, the intake and exhaust lobes centerline distance is known as lobe separation angle. by xstfudonniex Fri Dec 12, 2008 5:24 pm, Post 01 Choosing the right lobe separation angle for your LS cam shouldn't cause anxiety. by trmnatr Sat Dec 06, 2008 10:45 pm, Post such as 290 @.050? To further minimize any dyno variations, the engine's oil and water temperatures were kept the same for each pull. JavaScript is disabled. This wave tuning is what helps performance engines achieve volumetric efficiencies of more than 100 percent. 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.
108 vs 110 lobe separation