My guy in 3 months has proved more combinations than ls1tech has for the past 12 years

If I ever get a chance to either build or simply can swap an LS all I have to do is watch your video series, pick the combo I think will work best for my intended vehicle and just duplicate it. You’ve take all the guess work out of it for us all. What a service you’re providing. Thank you.

I did the same test on a 4.6 2v back in '09 for my buddy David Vizard... My results mirror what you came up with on the LS! David is a huge fan of tight LSA's and he even has come up with the controversial 128 rule.... Awesome job like always!

What do I think? Hell, I don't know anymore...between you and Engine Masters everything I learned as a kid was false. Can't wait for the next installment.

David Vizard published very good book with great explanation on LSA and how t choose best one for particular application.

David Vizard been saying that for years and I believe it`s true. 106 seems to be the magic number for circle track and higher compression, 2bbl seems to like the wider LSA along with bigger CID like 454 and bigger.. There are so many contributing factors I don`t think a person could pick the perfect cam with out a dyno, back when I was a kid cams were listed by lift, duration (advertised) and overlap. I think Isky was one of the first guys to start tightening up the LSA and he made a high mark to reach for

Around 50 years ago I was taught to run narrow LSAs as much as conceivable to help capture cylinder pressure at higher elevations like in Denver. We were always happy when we got cams at 110, and really happy at 108.

Been watching david vizzard lately and he has a formula that puts this engine’s ideal lsa right around the 108 that made the most power, maybe he is on to something. Oh yeah and as always another great video by richard

My NHRA SS/J 66 Chevy II uses a custom ground solid roller with a 109 LSA I had ground using David Vizards 128 rule. My heads are NHRA Superstock legal Edelbrock highly modified by Edelbrock to coincide with NHRA rules. I shift @ 9000 so its wound up pretty tight and pulling off a consistent 8.60s with a .060 over 327 and M22 tranny is no easy feat. Listening to David Vizard and reading his books has made not only my Superstock fast but my Stock Eliminator K/SA Monte Carlo SS (with the factory L69 305). This test Richard just run backed up the 128 rule big time. For big blocks and Fords is 127 and he has videos on it if you are wanting to learn. Thanks for this video Richard you are very entertaining and easy to listen to unlike Freiburger and Dulcich.

Very interesting. I run in a tightly-regulated race club where LSA is basically all we have to play with (DOHC, adjusting stock cams) and we are typically living in the realm of 103-105 LSA. Our duration numbers are pretty high (streetbike engines) and we operate around 6000-12000 rpm. There is definitely a point of diminishing returns in wide LSA for top end! This is why we test!

Yes, it would be cool to see this test done on a 5.3L and 5.7L

Richard giving the people what they wanted. Awesome. Patiently awaiting SBF combos.

my take away: don't rush out and buy a camshaft on a 108 degree lsa. the 112 degree lsa cam is so close to the same power numbers it makes more sense to use it in a speed density fuel injection system because it gives better vacuum at idle and allows the map sensor to work correctly.

I was always told this and all our drag cars had the super tight LSA. But it was nice to see it in a graph to prove the point. Richard. Your the man.

Great job explaining LSA. Tighter more chop & more bottom end, wider less chop more on the top ! Thanks Richard!

Good video - people are realizing the tighter LSA means more acceleration torque AND NO LOSS upstairs- bigger displacement responds even better, of course vacuum drops due to more overlap and worse throttle response below 1500 to 1800, so an automatic and smaller engine should use a somewhat looser converter, BUT make sure converter stall speed is below top gear or overdrive RPM at highway cruising speeds.

The work never ends... Same test with turbo, supercharger and nitrous. Thanks for everything you do Richard!

Great test but with the 108 LSA looking better all the way it would have been nice to see another with even less LSA to see what would happen.

Back in the70's Isky and Clay Smith had a bunch of cams at 108, they were ahead of the curve compared to most cams. They also made very good power through out the rpm range. Nice test

You run tests I've always wanted to see. Thank you again for the awesome data you create and provide. Great job!

Truck norris cam makes sense now. I just revisited this video and glad I did. Truck norris is what I'm rolling with. Thanks

Just subbed, you really get to the point without unneeded banter! Thank you for an informative video

Gotta have that chop! Besides power down low with good torque is what I need!

Welp, I'm seeing this two years hence, but of course it's still very interesting. I've wondered the same thing about LSA for many years now. I'm positing the lower numbers at lower RPM for a wider LSA have to do with how the wider LSA bleeds off more cylinder pressure. Both valves are still open for several degrees of rotation, and you can't build cylinder pressure until they are both shut. My bit of homework on the newish cams sold for use on low compression engines run in line with this. Comp Cams' Thumper series, Hughes Engines' Whiplash cams, all have very tight LSA numbers. As you say, they give the hot rod guy the lope he likes, but the smooth out early. And they actually make more cylinder pressure than an OEM cam. The lope isn't desirable for an OEM for sale to the general public. All in all, very interesting and thanks for taking the time and effort to do it. One other factor I've wondered about for years, how about the installed angle of the cam? Would installing the 112 LSA piece, maybe even the longer one, make these valve events soon enough to compensate? Thanks!

Good one thanks. That's what I wanted to know and that was my hope that tighter lobe separation will give me better low-end power and a wild chop without increasing lift and duration.

Nice this is a topic iv always thought about. Few things I knew for sure was the lower the LSA = more chop @ idle but also slightly more difficult too tune. Now we need the results on smaller cube, less radical builds like your budget 5.3 & 6.0.

All you read/hear is tight LSA = peaky/narrow powerband that will fall off up top. Yet every dyno test ive seen they actually have more spread between between peak torque and power.

Just installed a Mutha Thumpr (109 LSA) in my LQ9 swap. This videos gives me hope.

Wow! Great video Richard! Had no idea that a tighter LSA (with choppy idle) would make more low end power!?!?! NOW.....I can have the best of both worlds!!! I can put a 108 LSA cam in my work truck, have a bada$$ idle and tow my trailers (enclosed tool trailer, 6T flatbed and my I/O boat trailer) all day! ALL your videos have awesome content and enjoy the heck out of them. I watched several of them more than once to make sure I'm absorbing the content for my LS/OBS swap coming up.

Great test 👍🏻 Would be great to see these exact three combos now fitted with a blower. Richard keep up the great work

Tell em what happens to the vacuum. The brakes 😁 Great video 108 centers rock ⚔

OVERLAP Ls9 = -24.50 Crane 210/218 122.5 = -18.00 Crane 232/242 (.624/.624) 120 = -3.00 112 = 13.00 108 = 21.00

Exactly what I was saying on a different video about the intake tests. Just because you have a long runner intake you don’t need to run a wider lsa. The reality is that tighter lsa cams tend to make more power even more so when naturally aspirated. Thanks for the video!

If you can only run a test over a limited RPM range .... Why don’t you run two tests? For a street car I would like to see what is lost low down.

Have your ever read David Vizards bbc books? He says you add lsa with each point of compression increases, AND as you increase stroke, you take away lsa. Going from a 110 to a 108 on a 496 was worth 25hp peak and torque everywhere.

very interesting results, ill keep this in mind as are thinking of getting a custom grind for my lsx 7.0

You said you did this in a reply to my comment on an old video and I looked a couple of times to find it, but now I see why I didn't find it. Now take the 112 and change only lift. Then do the same with the duration would be awesome.

I find it super interesting. Well done sourcing exact same spec cams other than LSA. If any cam had even a slight duration or lift difference, results would be controversial. Power increase up top with 108 lsa cam is confusing. Could it be due some kind of harmonics? Matching with Intake runner length or something like that? I’d love to see a test with same cams on different displacement Ls motors. Thanks for sharing. Love the content you putting out.

GREAT test Richard! This test repeats ALL other dynos I've seen where only LSAs are changed. Yet you read all the tech info they say the reverse. Well done.

Thanks Richard, you have answered my next cam choice. This info is priceless and worth gold.

I would like to see this test run again, but this time with the icl set to 108 for every cam. 12 degrees advanced for the 120lsa, 4 degrees for the 112 lsa, and straight up for the 108 lsa.

Nice I loved my Lunati Bootlegger in my sbc 406. 108LSA nice chop great power band. Running a Summit cam in my budget junkyard 307 build, 106lsa, gm 601 heads that I cleaned up a bit. Fun little mighty mouse motor. Going to build the 406 right and put a forged rotating assembly in.

Awesome, awesome video Rich... Guess I now know what to expect when I install that Truck Norris cam into my Pontiac LS2... More chop, and more down low-mid range, and hell maybe even more up top as well

This is another great post by RH. That 210/218 duration cam might really wake things up with 102-106 LSA

Now I know why I have always ran a 112 LSA advanced 4 degrees. Intake is always more critical than the exhaust. Also with a 10 - 12 degrees more on the exhaust duration. This is what I have found to work best in the vast majority of cases, over the last 45+ years. What we also found was that a 108 LSA, (MPG) suffered on the street. It was not worth the loss of gas mileage for the little HP that was gained. That was why we started advancing the camshaft, and it worked...

Man, I have always wondered what the change in LSA would affect!!! Thank you for the information!!!!

Hey Richard, camshaft theory is fascinating to me and watch this video often. In fact, I had a custom Bullet Cam for my 454 ground partially based on this video. Theorizing here, a tighter LSA generally increases cylinder psi, because it increases the dynamic compression, which may have contributed to not only the expected bump in low speed torque but also the power across the board.

Richard, you say the dynamometer won't measure the entire operational rpm range. But last year when I was building my Cadillac stroker, I spoke with the engineer at "The Cad Company" extensively. He brought this very subject up in our conversation. Oddly enough he mentioned Westech specifically. He said: "Westech says their dyno won't measure across the whole rpm range, and that's just BS". Said: "we have the exact same dyno, and we had the factory come out and did a add on modification that allows us to do the entire sweep from idle to redline accurately. They could easily do the same" So, maybe this is something you'd want to have Westech look into? If they aren't interested in cooperating, you could still do both a low, and high sweep. At least then we could compare the relative low and high characteristics of the different cams, or whatever you are testing at the time. I think the duration on these cams was too long for your rpm cutoff point. Like you, I would expect to see a sharper drop off in the curve for the shorter LSA cams on top. I think you would see an even more dramatic drop on the low end, also. My experience has been that a closer LSA tends to concentrate the power in a tighter rpm band. Thanks for this data, though. Anything at all in this regard is helpful.

I've had the opportunity to work with a few engines using a 108LSA over the normal off the shelf selection. Two 347 SBF's and a 388 LT1. All engines were amazing street strip combos. Still had manners down low, came on strong in the middle and ripped up top. For the 330 to 400ci range, I don't think it can be beat.

I think you needed to go below 108 to see the drop off on the top end because 108 is about the optimum lsa for that combo.

Lobe profile helps with valve tran stability and longevity allowing the lifter to follow the lobe more accurately hopefully without bounce. Possibly allowing larger cams with less negatives towards the valve train.

another way of seeing this for someone with a DOHC engine. Is the stock camshaft timing, then advancing the exhaust camshaft 4 degrees. then another 2 more degrees. ( however because everything has an equal and opposite reaction this is Also decreasing the overlap period by closing the exhaust valves that many more degrees before. Thus decreasing the overall amount that both intake and exhaust are open together at the same time.)

I feel like a certificate is in order after watching all of your videos.

There is an exception to every rule, with a few exceptions.

The reason I widen my LSA is to soften up the bottom end for engine longevity. I have noticed with my twin turbo 406 sbc I snapped 3 different rods before I switched from 108 to 112. Now I have had the same engine for 3 years with no noticeable change in performance down low.

Richard! People want that down low power for part throttle feeling of the motor. If you have a gutless bottom end you feel it trying to accelerate from a stop. Even though you don’t floor it there people still want to it to feel powerful everywhere. ONLY if it doesn’t have a higher stall converter

Let's see the same test on a 4.8 (same cam). I think the smaller displacement will emphasize the torque differences much more than the stroker, and show the curves better.

The only thing I would like to see included in this test is Idle vacuum. Have a set rpm, 800rpm or something, and tune the idle for maximum vacuum to see how smooth they idle.

From what I understand, which ain't much, it's all about the EVC point. Start there, and adjust the rest. This is per the great Harold Brookshire, and Mike Jones, and even David Vizard. It would be interesting to see that installed +4.

subbed! totally explained LSA's to what I was hoping to understand on paper! also totally explains my ls swapped cruisers cam behavior now too

The stroker needed the overlap. Stock 5.3 will limit how much overlap you can throw on it I think. We need to test that!!! Title “how much overlap a 5.3 can use? How does the graph looks!!

THIS IS WHAT IVE BEEN WAITING FOR!!!

The biggest issue missed by many on an LS cam selection is the intake design is very much like and or mirrors the characteristics of an individual runner intake, and how a tight LC cam creates a reversion pulse, which on a common plenum intake can be masked, as another runner will pick up the reversion pulse, however on an Individual runner intake, or most non common plenum LS intakes it makes a huge difference

Great video, I would like to see this type of test ran on a stock 5.3 and 4.8.

Would love to see this focusing on higher rpms on a 4 cam mod motor. Would be super easy to change only LSA without even pulling the cams

Interesting to see that most basic "Turbo cams" have a wide LSA if tighter LSA produces more power down low. I would think that's what you'd want to spool the turbo up faster on most combos. It seems like you can't go wrong with tighter LSA for a street/strip motor where you aren't worried about driveability. I guess that's why the turbo cams have wide LSA, just to help driveability. Interesting to see for the build I'm trying to piece together, looks like I might try and spec out my own cam for the fun of it and see where it takes me :)

I’d definitely like to see this on a smaller displacement engines possibly comparing the 4.8L/5.3L to the bigger 6.0L is also be interested as to how the LSA can affect specific boost pressure

When you change LSA you are probably changing ALL four valve events. I believe it was Billy Godbold who said that they use wider LSA because people always think bigger duration is better, so they spread the lobes so it doesn't have as much overlap. The result is soft low and midrange torque, and small gains up top. Most LS combos should be 106-111 range for best power.

I was always told wider LSA meant less valve overlap so it would be more efficient. When used with forced induction it reduces blowing fresh air and fuel out the exhaust. I could be wrong though.

How about some lsa +0 vs +2, +4, +6 intake lobe advance. That type of data would help understand ground in advance a bit more while helping with camshaft selection.

I would have thought the 108 lsa would have made a peakier power curve, not flatter..... good info!

Now do a video on which one SOUNDS better.

Nice, separating fact from fiction as usual top stuff,

More awesome work Richard, you're cranking out the best content on YT right now! Now can we see the 108 LSA vs the 120 LSA with turbos? Maybe even SC? I know you saw it's the same, but we'd love to see it proven!

I am learning so much from your videos! Thank you and keep them coming!

You are right when you say the cams are nearly identical other then the LSA, However the cam timing events are completely different throughout the entire rpm of engine/camshaft so your truly not just changing the LSA it's impossible

Interesting how it gained without really losing anything with LSA. I guess the next thing to do like you said would be to change the engine size and test again 👍

Odd request..... but I would really like to hear the idle difference in all 3 cams

Was just trying to choose lsa for my new tsp cam last night! Thanks for the test Richard, you're the man!

I have an LM7 5.3L Gen 3 bored 30 over. I have watched a lot of your videos and love them. My cam and engine spec are: Custom grind. Cam Motion - 210 int/ 218 exhaust/ 570 int and 570 exh lift with a 110 LSA +2. PAC 625 springs. Stock heads with a 3 angle valve job. I will be adding Long tubes and a full 3" exhaust with a cut out for fun.

A lot of great info on this channel. Clearing up a lot of misconceptions. Keep doing what your doing brother!! We appreciate you!

I want to hear the difference in the LSA of the cam

GM uses the ASA cam to increase performance in several of it's crate motors, i.e the 525 hp 6.2. This cam has a lsa of 110 and you can use stock ls3 springs. I'm currently running this ASA cam in a 6.0 with ls3 cylinder heads. great videos

Another great informative video Richard. Thanks for showing what’s behind the curtain when it comes to making power.

I don’t think the smaller engines will have such a dramatic change as the test engine you used. Prove me wrong😏

Hey Richard do it on a 5.3. So some budget guys can say hey I know what kind of LSA to order for my junkyard swap and what not. It would be nice if you did a 5.3 or 6.0 nitrous big bang engine. take a stock engine put some good rods in it open ring gap and a strong cam. and love it with nitrous as you do boost. we all know boost makes power. but lets see a nitrous engine get turned up. 150 shot aint enough. lets see u push it as far as you can take it. 300-400-500- hell max out the system if you have too. lets see some 800-900- or even 1000hp nitrous 5.3 or 6.0. no strokers we wanna see what u can push out of a simple junk yard engine on the juicy juice

I’m waiting for cam tests like the 228r with 112 Lsa. All your tests have split duration. I’d also prefer stock block configuration. I feel more viewers can relate easier. Maybe throw in more ls1 engines too. Overall great job! I enjoy your videos.

I think the difference between LSA’s would have been more pronounced if the duration specs were lower. I believe the combination was slightly over camed on the duration side so it wasn’t as picky about the change in LSA.

Texas speed just came out with the BFD cam that has a LSA of 108. I would love to see that in a LS1

Would love to see one with 106° have run them in my 6 banger & Holden V8's (among other combos) for around 30 years but never in an LS! I want to run boost on my 6 Banger with Triple Webers but is just one of those things that never happened (got ripped off a few times with shops I took it to, to get manifolds made etc)

I don't know if Richard knows this, Crane measures their advertised Cams at SAE standard, .004s. THEY Also keep the duration spread down between ADVARTISE and .050s, making it like a SAE cam.

This is very interesting to anyone running a DOHC as we can change the LSA without changing cams.

Drop them in a baseline junkyard 4.8L and show us the numbers. So many tests show built engines, but how would these work for a cam+springs+tune only on an otherwise stock 4.8/5.3? I think a LOT more people are looking at ways to bump up the power on a budget, but at the same time I like seeing the 500+ for the race guys (just not as often as the "how to add power for under $1000" tests).

How would the lsa affect power adder?. Nitrous,turbo,etc..test it please

Thank you, Richard. I was going to ask you this question and I recalled you always telling us to refer to your long history of videos. Lo and behold you had one on LSA that really helped to answer my personal question, I wanted to know if I could go to a lower LSA on my EFI equipment BBC. All the cam specs say not for EFI. But I know what you normally run, and I thought you had my answer. I'm not that concerned about idle quality and would like more chop at idle for my 70 BBC Chevelle. The only other thing I'm wondering is what effect positive or negative a smaller LSA will have on Nitrous. I'm off to search for that video... Thanks for all you do! Mark

YOUR VIDEOS ARE GETTING BETTER AND BETTER. I LIKE THAT YOUR PUTTING MORE TECH DATA . I WOULD LIKE TO SEE A TEST ON HYDRAULIC LIFTERS VS LIFTERS LIKE RHOADS.

Was the cam advance changed for each cam to keep intake valve closing the same? I have to wonder how much of the low end power was from the earlier IVC of the 108LSA cam then just LSA (or overlap) by itself. Obviously changing LSA moves all the valve events, but keeping the IVC the same might be more of an accurate test of LSA? Especially since IVC is considered the most important. Great vids btw.

Idle videos would be a nice add to these videos, LSA tends to change idle characteristics correct?

This is why i love the mod motor. you can degree lobe seperation angle, intake and exhaust centerlines, and basically tailor the specs to fit your application.

Thank you I been asking you to do this for 6 years!