108 vs 110 lobe separation 108 vs 110 lobe separation

The world of fuel injection is where wide LSA cams like the 113 really shine. 110 LSA: On the other hand, 110 LSA is a wider LSA with almost no overlap. 108* or narrower lobe separation angle (LSA) is "Narrow" and 114* or wider (up to 117* or 120* for stock cams) is "Wide" , with 110 to 112* being the "normal" hot-rod cam. Say you have a cam ground on a 115 and the other on a 110. any input is appreciated guys, thanks. As usual, Marc (aka Master) is correct. The 108-degree cam (blue lines) outperformed the other two, but idle quality suffered. Idle quality was rough and the vacuum gauge showed only 9.8 in-Hg (inches of mercury). 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. The result sounded wonderful, but it didnt rev as enthusiastically and it made 30 less horsepower than normal, says Lawrence. If the overlap phase occurs too early, it will create an overly rich condition in the exhaust port, severely decreasing the gas mileage. It is dangerous to be right in matters on which the established authorities are wrong. If it occurs too late, it will lean out the cylinder and greatly hinder the performance of the engine. The standard bore block was then stuffed with a 4340 forged steel 4.0-inch crank and 6.125-inch rods, along with a set of flat-top, forged JE pistons. I think the compression ratio has something to do with LSA too. The takeaway from this test is camshaft LSA is a double-edged sword. What Are The Wastegate Stuck Open Symptoms? The second cam would have a rougher idle, produce more torque and would rev quicker. A wider LSA moves intake- and exhaust-valve events farther apart and creates less overlap, which hurts intake-wave tuning. 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. 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. Hey guys, can anyone tell me how rough of a idle a cam would be with a 108 lobe separation? by xstfudonniex Sat Dec 06, 2008 4:21 pm, Post When you purchase through links on our site, we may earn an affiliate commission, which supports our community. 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. " - Voltaire. Usually, this separation angle ranges from 95-degree to 120-degree. 1-3 Cognitive impairment is common in both FLE and TLE and adversely impacts quality of life and psychosocial functioning. 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. The intake lobe centerline is measured in crankshaft degrees. You can modify the lobe center a little bit but not enough to change the actual overlap of the grind. 110 LSA: But here, quite surprisingly, you have to face the reduction of the EGR effect due to the 110 LSA. I wouldn't assume 4 links fuel requirements will mirror yours at all. One segment that truly benefits from a wider LSA is the marine marine market. . Is it a hydraulic roller as well? "Ninety-nine percent of cranking compression is dictated by static compression ratio and intake-valve closing point," said Comp Cams' Billy Godbold. It is possible to advance and retard the timing events, but the distance between the centerline of the lobes will remain constant. Also If you go with 112 lobe centers, you create less valve overlap which will increase your compretion. See all 14 photos 13 The three power curves indicate that the wide (120-degree). 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. Okay, have a sigh because you have opened the right door. Its the shifting problem again with your Chevy! Typically, narrower lobe separation develops peak torque at lower rpm and widening the separation tends to build peak torque higher in the rpm range. All rights reserved. Also, the wider LSA contributes to chassis stability in drag racing by avoiding the delivery of a ferocious blast of power that would break tire traction. Let's just talk lobe sep angle. 1966 Toyota Landcruiserunder construction. by ANT Thu May 15, 2003 6:44 pm, Copyright 2022, S&S Motorsports LLC, All Rights Reserved - Powered by phpBB Forum Software phpBB Limited. lobe centers and lobe separation are 2 different things . The absence of engine knocking ensures that your car engine is reasonably combusting the fuel. The piston and cylinder damage possibility is pretty low at 110 LSA. Methods: We evaluated 30 individuals with PD (62.47.2 years) and 22 age-matched healthy controls (61.06.4 years). whats the difference in how the car will run. music to your ears? A cam with a tighter LSA will require a looser torque converter, may not be able to run vacuum-assisted brakes, and doesn't play nice with fuel injection. When you purchase through links on our site, we may earn an affiliate commission, which supports our community. But, you may find it quite shocking that the piston-to-valve clearances decreasing rate raises the chance of damaging the valve by the piston. 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. So, choose the perfect lobe separation angle for your engine, complying with the requirements of your needs. 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. Required fields are marked *. by mike thompson Tue May 13, 2003 4:03 am, Post 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. 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. You can research your heads to find out where yours are, but honestly I don't think it will be worth the effort on a tow vehicle. The 120-degree cam minimized torque production through most of the curve, while the 112-degree cam offered more torque but slightly less peak power. But you always have a cam card with the engine. And better gas mileage. Average power was also down, but the engine pulled ahead of the 101 cam at 5,400 rpm, picking up 6.5 hp at peak. Unfortunately, good street manners are often at odds with performance, as wilder cam timing usually decreases idle and (low-speed) driveability. I'm sorry to disagree with that incredibly well written article, but lobe separation by itself is absolutely freaking meaningless. 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! 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. You get a better idle, vacuum, and response from a 112o-114o lobe. That lopey idle that is universally loved, and part of the allure of a tight LSA cam, is actually misfire caused from a combination of exhaust dilution in the intake manifold and poor cylinder filling at idle. Really wide lobe separation angles are used in boosted applications. But, at 106 LSA, the cranking compression may increase above the standard PSI level. Do you like to go fast? Looking at 108vs. Similarly, 110 LSA is also found to be a more fabulous performer in several mechanical aspects. A commonly held misconception is that intake/exhaust overlap contributes to lower cranking compression. JavaScript is disabled. 106 LSA: You can see an increasing EGR effect at 106 LSA. However, the plentiful exhaust overlap (31 degrees) meant there was lots of exhaust dilution at low engine speed and high vacuum. by flat4racer17 Tue May 13, 2003 9:12 pm, Post 108 vs 112 lobe seperation. Increasing the EGR effect has a good side in that it reduces the amount of oxygen in the combustion chamber. It affects the amount of valve overlap; that is the brief period of time when both the intake and exhaust valves are open. But it is a piece of good news for your engine. pump gas, no additive's as well, runs good, i will put the highest octane in, which is 93.. The 402-inch LS2/LS3 hybrid stroker started out with an LS2 aluminum block. 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. Simply put, both 106 and 110 lobe separation angles have many advantages and disadvantages. I'm surprized at these questions as well as some of the replies. " 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. 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's not having what you want, it's wanting what you've got!" I have Crane hydraulic link bar style roller lifters, so I dont have to use the spider style. 09 All testing was run through a set of 1 3/4-inch long-tube headers and 3-inch exhaust. camshaft is a Cranecams F238. its got a 3.73 posi and the Stock 4 speed with a very low 3.42 1st gear. Pick the cam with the valve timing events that fit the engine best, forget about LSA, it is only a result of the events. The graph above compares intake valve closing points of the three cams used in the test. The final cam was tighter still, with a 108-degree LSA. If you take any of the . Thanks again. The exhaust has an opening even and a closing event. The Fora platform includes forum software by XenForo. 01 Choosing the right lobe separation angle for your LS cam shouldn't cause anxiety. The #1 intake lobe centerline is usually between 100 from the intake to the exhaust and vise-versa.Thats why a performance cam will usually have a rougher idle than a stock one. Is There a Sequence? I think you are asking a lot of a cam . - Sheryl Crow. by bug1914 Tue May 13, 2003 2:56 am, Post Lobe Separation Angle, or LSA, is the number of degrees that separate the peak lift points of the cam's intake and exhaust lobes. The engine has AFR heads, Crane rockers, a TCI balancer, a Scat Rotating assembly with Mahle pistons, an Edelbrock RPM Air-Gap intake, an MSD ignition, and an Aeromotive fuel system. 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 really comes down to the application. http://www.mustangworks.com/cgi-bin/moi-display.cgi?220, http://www.popularhotrodding.com/en6em_camshaft_specs/lobe_seperation_angle.html. Post Most cars use more than, Read More Does It Matter Which Ignition Coil Goes Where? 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 Exhaust reversion is another undesirable side effect that can be caused by overlap. Some of the confusion on this subject comes from what the meaning of "bottom" and "top" is to the speaker, I suppose. With the first cam loaded in the engine (the 101 LSA) Westech's Steve Brul made three dyno pulls, the average of which was saved to compare to the next cam. The 110o will make more power overall. 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. It produces peak torque earliercoming on quicker and strongerbut also it falls off quicker too. A lower efficient compression rate leads to a higher fuel consumption rate by your engine to produce higher power. 03 The 4.000-inch crank and 6.125-inch rods were combined with a set of forged asymmetrical pistons from JE. On the cranking compression test, Brul recorded 175 psi, a 10-psi drop from the outgoing 101 cam. 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. But that doesnt mean high-strung racing engines cant see gains, as well. Nitrous engines, which make plenty of power and torque, often run wide lobe separation angles to moderate cylinder pressures and temperatures. Consequently, decreased torque rate often leads to more energy consumption. by Kdub Sun Dec 07, 2008 1:20 am, Post I've heard similar cams (only about 5*'s off) and they have a nice rumble to them. This process slows down the reaction rates of the air-fuel mixture, causing temperatures to drop and preventing the engine from overheating. You must log in or register to reply here. That was just a glimpse of the information you were looking for. The Fora platform includes forum software by XenForo. by Kdub Sat Dec 06, 2008 11:05 pm, Post It affects the powerband and temperament of a motor more than any other single part, and a slight change can turn a car from a mild-tempered grocery-getter to a downright nasty machine. It idles very well at 650 rpm with a nice lope and runs strong. Cam swaps are all the rage and for good reason. In the 106 LSA, the engine can reach the maximum torque, making the driving more efficient and saving energy. 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. Professionally ported & polished iron 4V head with titanium intake valves, stainless exhaust, titanium retainers & keepers & dual springs. Supercharged and nitrous race engines typically benefit from a wider LSA because they dont require as much overlap for exhaust scavenging as does the naturally aspirated engine, continues Bolander. 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. Lobe separations on 383-406 cids.104-106-108-110? Lucky for us, Brian Tooley Racing stepped up with a dual spring package that allowed us to safely run our 0.624-lift cam. 238/248 duration, 300/310 adv. Simply put, the lobe separation angle (LSA) is a measurement of how the intake and exhaust lobes are phased with each other. 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. too much for the street? 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. An icon used to represent a menu that can be toggled by interacting with this icon. 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. If you shift at 7500-7800 add 4-6 degrees to both intake and exhaust and spread the lobe separation to 108-110. All testing was performed with an Aeromotive fuel pump feeding a set of 42-lb/hr injectors. 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. Check out the Comp Cams catalog, even the biggest hydraulic rollers use 110. 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. Hopefully it turns out great. Test 1 was easy. Re: Lobe separations on 383-406 cids.104-106-108-110. Well get out of that stocker and build a hipo motor for your VW. Camshafts with a substantial overlapping tendency should not be used in vehicles driven on public streets. To reiterate another point, I realize that wider LSAs tend to broaden the power band, but for a car I would like to bracket race a bit, as well as enjoy on the street, I was told that a narrower LSA will help the car accelerate at a faster rate. They also reduce stress on the outdrive. With minimal overlap and a steady manifold vacuum signal, they work great with fuel-injection systems and are the norm on modern pushrod engines, such as the LS and Gen III hemi. Thanks. In this segment, I am going to compare those two lobe separation angles based on a couple of mechanical factors. I personally prefer to sacrifice the small amount more power for better idle quality. 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. Coupled that with the low first gear of the five speed, it ought to create some real traction problems. Because during the lower units oil change, you can go through the issue that the lower plug, Read More Yamaha Lower Unit Drain Plug Size [Explained Everything]Continue, Among the crucial parts of a vehicle ignition system is the ignition coil, also called a spark coil. The same is true for intake valve closing. Cylinder-head flow and LSA are directly related: as a rule of thumb, the better the head flows, the wider the LSA can be. If the cylinder heads are the lungs of an engine, the camshaft is the brain. Read More Chevy 350 Ignition Coil Location And Everything About ThemContinue, What causes a car to bog down when accelerating? 07 Though the CNC-ported heads offered plenty of flow, it was necessary to upgrade the supplied valvesprings. It will sound lovely I'm sure. I bet you won't see a bit of difference. We do not stock profiles with 109 or 114 lobe centers. somthing to that aspect. Introduction. 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. I would say 114-117* would be a normal 1960's stock cam range and 117* to 120* is more what we see on modern engines.