Yeah but do the experiment on the dyno and tell me your intuition is correct. Higher overlapping lets less oil fall through the oil inlet. There are General guidelines about the effects of LSA but it should not be the deciding factor in choosing a cam. Also If you go with 112 lobe centers, you create less valve overlap which will increase your compretion. When you don't have any overlap, you can't have any wave tuning. On a tight lobe separation, like 106-108 degrees, the engine will build torque quickly and reach its peak early. Powerband serves a massive contribution to the acceleration car. 112 vs 114 lobe centers You cannot tell the differance in the two . Fixing the ignition coils is essential when you experience issues like engine misfire and the Check Engine light that wont go off. But, the narrow or broad powerband choice varies from person to person. AquaTraction Vs SeaDek: Which One Is Better For you? Required fields are marked *. 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 114 cam will give more low end torque, good midrange, less power up high. Aeromotive; 913.647.7300; AeromotiveInc.com, AFR Heads; 661.257.8124; AirFlowResearch.com, Federal Mogul/Felpro; 248.354.7700; FederalMogul.com, Mahle; 248.347.9700; Mahle-Aftermarket.com, Scat Enterprises; 310.370.5501 ScatEnterprises.com, SuperFlow Dynamometers and Flow Benches; 515.254.1654; SuperFlow.com. For a better experience, please enable JavaScript in your browser before proceeding. I will be running an Edelbrock Performer RPM, with a Quick Fuel 750cfm with a screw adjustable vacuum secondary; it's called the Pro-vac. Introduction. also,, wider will produce a wider and more flat torque curve that doesn't fall off as abruptly up top rpms. The tighter the lobe separation angle, the peakier the power curve will be, confirms Bolander. Again, these are general bits of conventional wisdom. I probably would have gone with 3.55 gears had I knows better.. It also depends on displacement, some guys will run a bigger cam and widen the LCA to give a better idle but in my opinion it kills power. Post I think you are asking a lot of a cam . lobe centers and lobe separation are 2 different things . Ultimately, it comes down to how you want the engine to run, the car's intended purpose, and what you are willing to tolerate. 4-linked72, what cam are you using that has a 108 LSA? The 110 is probably a better choice for a performance street engine. Part Number: HRS-CL120325-08. 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. For a better experience, please enable JavaScript in your browser before proceeding. The same is true for intake valve closing. 02 The 402-inch stroker short-block combined an aluminum LS2 block with a 4.000-inch crank and 6.125-inch rods. The graph above compares intake valve closing points of the three cams used in the test. by flat4racer17 Mon May 12, 2003 1:40 pm, Post 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. by randy331 Sat Dec 06, 2008 10:00 pm, Post indeed, expect low vacuum with anything lower than 110-ish. Engine builders Chuck Lawrence, left, and Doug Patton. A 110-degree lobe separation angle means that the peak opening points of the intake and exhaust lobes are 110 degrees apart. Tests 2 and 3 meant dissecting the motor on the dyno to get the old cam out. I have used some cut on a 110 that worked well too, but they never sounded as good as the tight ones. What brand and what are the specs on your cam, 4-linked72? It affects the amount of valve overlap; that is the brief period of time when both the intake and exhaust valves are open. 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. It may not display this or other websites correctly. . or just enough to keep the neighbors pissed? Ed JTO learn to park Joined May 31, 2009 180 Posts After the next three pulls, it was clear the 113 cam was way down on low-end torque. My duration will be about 230 degrees. VerticalScope Inc., 111 Peter Street, Suite 600, Toronto, Ontario, M5V 2H1, Canada. 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. Re: Lobe separations on 383-406 cids.104-106-108-110. Check out the Comp Cams catalog, even the biggest hydraulic rollers use 110. That notion is completely false. Simply put, both 106 and 110 lobe separation angles have many advantages and disadvantages. 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. We will safeguard your e-mail and only send content you request. by mrsmythe Tue May 13, 2003 5:45 am, Post The piston and cylinder damage possibility is pretty low at 110 LSA. Before getting to the cam profiles, we had to make sure we had a reasonable test engine. Ultimately, it makes the 110 LSA an oil-consuming LSA. 110 degrees on the lobe separation angles. The taller lobe seperation will have a longer powerband but will have to rev higher to make the power than the lower lobe seperation! 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 valve covers, valvetrain, intake manifold, harmonic balancer, front cover, timing set, and cam were yanked. 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've properly tuned a performance motor, you create high- and low-pressure waves in the intake and exhaust that help cylinder filling," said Comp Cams' Billy Godbold. Simply put, the lobe center of the camshaft controls where the power curve is applied. Cylinder-head flow and LSA are directly related: as a rule of thumb, the better the head flows, the wider the LSA can be. Nitrous engines, which make plenty of power and torque, often run wide lobe separation angles to moderate cylinder pressures and temperatures. It's the scavenging effect of the high velocity exhaust gases rushing out that pulls the fresh fuel/air charge into the chamber. 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 mrsmythe Mon May 12, 2003 11:15 am, Post We will also custom grind any of the above profiles with a custom lobe center, for an additional $20 dollars. hydraboost is the same as a vacuum brakebooster, only the booster is replaced by a unit that does the same but under hydraulic pressure. Test 1 was easy. For your convenience, I am providing a comparison table to give you an overall idea about the comparison. The ported heads were capable of supporting over 700 hp, so we knew they would not be restrictive on our stroker. But it also has a lot of lobe separation. So, choose the perfect lobe separation angle for your engine, complying with the requirements of your needs. The #1 intake lobe centerline is usually between 100 The wider lobe separation angle closes the intake valve later and reduces cylinder pressure, so that is where it's detonation resistance comes from. As a result of this fall, the idle of the engine has to face suffering quite often. If you shift at 7500-7800 add 4-6 degrees to both intake and exhaust and spread the lobe separation to 108-110. The higher the compression and the higher you try and rev it, the more it will like a wider lobe center. "When the low-pressure wave in the exhaust reflects into the intake, the pressure delta actually helps pull air and fuel into the cylinder. Most street cams are ground 4 degrees advanced which boosts bottom end, throttle response, vacume, mpg driveability etc. And better gas mileage. 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. O onovakind67 Registered Joined Dec 14, 2001 6,242 Posts Nothing makes mouths drop like a car that sounds and looks like it can't keep it self still! 108: 110: 112: 114 . GRIND #: CRB3 3194 /3196 HR111. If you look at any given cam catalog, you will find that the majority of street-oriented cams fall in this range. Tuning this cam would be slightly more difficult due to the reduced idle vacuum, but it is hard to argue with all the extra power. If you take any of the . Simply put, the lobe separation angle (LSA) is a measurement of how the intake and exhaust lobes are phased with each other. by MELWAY Sat Dec 06, 2008 4:18 pm, Post 554"/577" lift. If you changed the lobe separation of a street engine from 112 degrees to 106 and didnt do anything else, adds Kaase. They also reduce stress on the outdrive. 108 is very tight producing lower vacuum and more of a 2 stroke "punch" powerband. Now its not shifting into 3rd and you are here. I'd also go to a 110-112 lobe separation angle. As you tighten the centers ( 108 ) the same engine will make MORE power through the mide range and top end. Now here is where it gets tricky. The idle quality was better with the 112-degree LSA but not as good as the wider 120-degree cam.The ultra-wide 120-degree LSA lost low-speed power and never recovered, but know that this wide LSA is often beneficial on positive displacement, supercharged applications. The 108 LSA offered the lowest idle vacuum of the three (down 4 inches). by bigjoe1 Sat Dec 06, 2008 10:48 pm, Post 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. Tight LSA cams make excellent low-end torque and have a beautiful power curve. If a street car has smaller lift and duration numbers, they might run 112 or 114. by xstfudonniex Fri Dec 12, 2008 5:24 pm, Post by xstfudonniex Sat Dec 06, 2008 4:21 pm, Post
108 vs 110 lobe separation
