FE Power Forums
FE Power Forums => FE Technical Forum => Topic started by: DuckRyder on April 12, 2026, 03:11:34 PM
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Am i missing something here?
- The numbers don't jive on the Wallace calculator?
- All the lobes from 212@.050 to 248@.050 are .587 lift?
For instance the HR 3 / Summit 8917
In order to get the numbers it has to be 279 advertised on the intake and a 108.5 ICL (cam card 278/107)
While realize that its very possible to have multiple lobes of the same lift with different durations, that seems pretty weird for all the lobes in the line to be the same lift and of 7 different durations. I don't really recall having seen that in other cam lines....
Any thoughts on this?
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I've found Summit sometimes makes or has, errors in some of their technical descriptions.
May not be Summit's fault... might be the tech sheet/specs from the manufacturer.
Seems like someone doesn't proofread those things sometimes...
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i'll let you know how it goes later this year, i've got one on the way that i ordered a couple days ago. i say later this year but it depends how the temporary (used) 360 runs when we fire it this week. if it's ok it'll go in my gasser til the end of the season, if not i'll be building up the 390 a bit sooner, lol.
neil.
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One guy is designing the lobes and they have a new in-house Landis grinder.
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So it seems Brian Nutter is the guy designing the lobes.(cant find a ton about him)
At least where they are talking about LS cams they claim the billets are US made and that the Landis produces a very good and accurate finished lobe. (who else is using those? Comp?, Howards?) Again talking about "PRO LS" cams its sounds like they are even machining the billets and doing the hardening.
Anyway... somewhat intriguing if true.
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It is Brian Nutter. I've competed with him in the cam challenge stuff.
All of your higher end cam grinders will have a CNC grinder like that.
Having experience in a specific engine family is what gives you a leg up with cam stuff. Just my opinion, but it's hard to pop out a line of cams when you've never built/dyno'd a specific engine before. Lots of different aspects when you look at valvetrain weights between cylinder heads, valve sizes, displacements, etc.
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Completely agree with you Brent, i just find new stuff for the FE interesting, particularly not so racy stuff.
Most of these seem to be aimed at stockish engines because they talk about things like "stock heads", "stock pistons", which makes sense for Summit. I do feel like got some things right for the "typical fe" like the increased split in durations which is probably the right direction for most OE heads.
The other thing is the math doesn't math on the cam cards, as mentioned this could just be a mistake, but every one I've tried to run the numbers on has not come up matching the cam card. That brings questions of course, and is IME very atypical.
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I don’t like quick moves on heavy valved engines. Would have to put a lobe on a doctor to see 110% what’s going on, but in a lot of cases the HI is a decent indicator of how quick things are.
I feel like a lot of the Ford stuff is lumped together, even saying BBF/FE on their website.
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I 100% agree with Brent
In the end, assuming they hit their numbers, quality is good, and the cores are available etc, IMO these are certainly a little better than most of the common off the shelf cams. No idea why their numbers are off, but you are correct. Could be an asymmetric lobe, differences in putting a lobe family on an FE core, or just bad documentation or a combo of all of it.
However, with these cams for the discount, you give up lift, which likely drives some spring choice changes as well as the obvious flow loss. You give up some seat-to-seat timing, which with a normal retainer and 3/8 valves will want some extra pressure. What I don't like is you have to go small to get overlap low enough to have decent vacuum on a street build, it'd be nice to have some wider LSA options.
Assuming the lobes are controllable, some spread on those bigger cams would be better for a stroker but given the lift and seat timing it'll still be a power cost over a custom. Saving 200 bucks is 200 bucks, but it comes with a cost.
On the flip side, there seems to be some decent split, good for stock or TFS heads, although maybe a bit excessive on a couple.
I would be hard pressed when digging deep into all the other blueprinting to recommend a generic cam, but if quality and availability holds, I can see a market for these
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So it seems Brian Nutter is the guy designing the lobes.(cant find a ton about him)
Brian is a very sharp dude. He has a lot of years in the industry - although little direct FE experience.
H put in a lot of time at Wiseco doing pistons before moving to Summit.
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Agree with points about quick events and overlap/LSA.
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I emailed Summit nearly a week ago asking for an explanation of the anomalies including My Gassers cam card not matching the one for the same cam on SummitRacing.com.
So far no reply other than the automated "we got your question" e-mail.
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I emailed Summit nearly a week ago asking for an explanation of the anomalies including My Gassers cam card not matching the one for the same cam on SummitRacing.com.
So far no reply other than the automated "we got your question" e-mail.
did you title your email 'fao brian nutter, cam grinder'?
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Not exactly, but i said someone needs to get with him and straighten it out... :-X
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. . . . . . asking for an explanation of the anomalies including My Gassers cam card not matching the one for the same cam on SummitRacing.com.
I'm not looking at the specific instance at hand, but having a camshaft "as measured" not matching the sales literature wouldn't be anything new! Now, hopefully somewhat close would be nice, but some deviation often is exhibited because that lobe was originally profiled for a different engine make, most often of a different lifter face (flat-tappet) or roller-wheel presentation which has an effect. ;)
If measuring at the valve, then there are many other possible aspects that may be unique to different engine valvetrain iterations which may influence the outcome also. :-\
Scott.
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So in the interest of science i was trying to follow ups on this with Summit.
So afar all i have gotten is that the lobes are "very asymmetric" which explains the discrepancies in the specs and camshaft calculators.
I could not get an answer on why mygassers cam card doesn't match the one on summit's website for his cam.
I also could not get any verification that the others are correct and the cam you actually get would match what you ordered.
If anyone would like to take up the investigation be my guest.
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. . . . . . asking for an explanation of the anomalies including My Gassers cam card not matching the one for the same cam on SummitRacing.com.
I'm not looking at the specific instance at hand, but having a camshaft "as measured" not matching the sales literature wouldn't be anything new! Now, hopefully somewhat close would be nice, but some deviation often is exhibited because that lobe was originally profiled for a different engine make, most often of a different lifter face (flat-tappet) or roller-wheel presentation which has an effect. ;)
If measuring at the valve, then there are many other possible aspects that may be unique to different engine valvetrain iterations which may influence the outcome also. :-\
Scott.
Well anything new cam wise or for that matter available and in stock for the FE these days is noteworthy even if its not so good (and in this specific case I don't know if it is good or bad). I've noticed the options on cams and related parts has been consolidated down quite a bit especially on the street, street/strip stuff. This seems to be a big trend especially with Comp cams (as well as keep raising their prices). They have either discontinued or made "Currently not available" a lot of springs, in particular stuff that is designed for FT cams.
I'd say the market is moving away from FT cams in favor of roller cams and in general trying to reduce the number of different parts like springs and associated hardware. I can see in the case of those Summit cams if they all have the same lift provided you don't end up with a hard to control lift profile because it really needs more lift then you can probably figure out a way to have one valve spring package that works for all.
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I reached out through for fun to see if we could modify LSA...no option.
Most will be a little rowdy for the power brake guys.
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67 - Agree always interested in new products for old pushrod junk...
Ross - I guess thats what sells every thing is on 110ish or tighter and talks about idle... there's a couple of these that could have been nice if a bit wider for less overlap - and assuming the numbers could be trusted.
Seems like Howards offers various LSA in the same cam but still on the 8 ish split program...
I'm sorta surprised we aren't seeing more of them in the wild but i guess the FE Forums aren't the market.
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67 - Agree always interested in new products for old pushrod junk...
Ross - I guess thats what sells every thing is on 110ish or tighter and talks about idle... there's a couple of these that could have been nice if a bit wider for less overlap - and assuming the numbers could be trusted.
Seems like Howards offers various LSA in the same cam but still on the 8 ish split program...
I'm sorta surprised we aren't seeing more of them in the wild but i guess the FE Forums aren't the market.
Howards are so lobe limited though and for some reaosn tend to be very low lift. I know it can be a smidge more expensive, but not much, but the only way around is custom. Bullet and Comp have a good lobe selection, good prices and quick turn, most everyone else, not so much.
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Well went and looked on the Summit page. Why the .582 lift across the board. It says so right in the ad and is about what I suspected which is spring selection
"Lift is set for compatibility with most aftermarket heads or modified factory heads."
"Most have additional lift so modern beehive or small diameter dual springs"
"specifically designed for stability at high-RPM with modern Beehive and lightweight small-diameter dual-springs"
As for LSA they are not all on 110. Depending on the cam it varies from 108.5 to 111.5 and some between 4-5 degrees advance cut in. Whether you can run a vacuum boost depends on not just LSA. You need to look at the actual valve events and other things effect it too like how open the throttle blades are. Usually I just add in using a vacuum reserve tank or vacuum pump and be done with the issue.
Another interesting quote:
"Lobe intensity is aggressive without being hard on the valvetrain, which is specifically designed for stability at high-RPM with modern Beehive and lightweight small-diameter dual-springs"
I think the best one is this:
"It's highly recommended the car be run down the strip before making any changes to the cam advance"
I will say at the price they are selling them it is cheap and you would have to try it and then you will know. Just keep in mind an off the shelf cam rarely is gong to be a perfect match for an application as it has to cover varied configurations. That said for many who have a budget they work "well enough". Just like Joe Sherman used to say the intake manifold is there to hold up the carb, can say the cam is there to move the valves. I've seem enough engines over the years with off the shelf and custom cams and it's a crap shoot. A custom cam is about the only way to go if your are racing to win, but street or street/strip depends on what is important to you. In my experience having a combination where all the pieces work together is more important. No custom cam can fix a screwed up combination (maybe can try to crutch it up, but won't fix it).
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Another interesting quote:
"Lobe intensity is aggressive without being hard on the valvetrain, which is specifically designed for stability at high-RPM with modern Beehive and lightweight small-diameter dual-springs"
Good buddy of mine with a Cam Doctor put one of the Summit cams on it. He said the intake side of the ramp is soft while it slams the valve down hard on the other side.
Some guy is gonna put one of these in a factory headed/valved FE and tear some stuff up.
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I was speaking generally about shelf cams seeming to tend toward "idle sound" seems to be less of a market for one that sounds close to stock. We got "rattler" and "thumper" i propose a new line "sleeper" ... 8)
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Another interesting quote:
"Lobe intensity is aggressive without being hard on the valvetrain, which is specifically designed for stability at high-RPM with modern Beehive and lightweight small-diameter dual-springs"
Good buddy of mine with a Cam Doctor put one of the Summit cams on it. He said the intake side of the ramp is soft while it slams the valve down hard on the other side.
Some guy is gonna put one of these in a factory headed/valved FE and tear some stuff up.
Not surprising. Guess they figure can get away with it using light weight valve springs and a high seat pressure. Seem to recall was a famous cam designer who used to slam the valve down too. Don't see it as a good way with that foot long valve stem on the FE. All I can say is it has cheap and available going for it. One thing I know for certain is I'm not going to be the guinea pig lol
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I was speaking generally about shelf cams seeming to tend toward "idle sound" seems to be less of a market for one that sounds close to stock. We got "rattler" and "thumper" i propose a new line "sleeper" ... 8)
Doesn't "high performance" dictate a lumpy idle?
If we go back aways Isky ground everything on a 108 LSA and kept the intake and exhaust duration the same. Said it gave the best performance. Factory stuff like the 427 SFT cams had a bunch of duration and a 114 or 119 LSA. Now take the CJ. cam. That lobe was used on the 351C CJ, 390GT,428CJ,429CJ and a few others. Amazing how an OEM decided those lobes would work in all those different engines.
As I said you really have to look at value event and really really best is if you can look at the lift profile. You can have two cams with the same LSA and duration, but be a lot different.
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I was speaking generally about shelf cams seeming to tend toward "idle sound" seems to be less of a market for one that sounds close to stock. We got "rattler" and "thumper" i propose a new line "sleeper" ... 8)
As I said you really have to look at value event and really really best is if you can look at the lift profile. You can have two cams with the same LSA and duration, but be a lot different.
Of course.
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Whether you can run a vacuum boost depends on not just LSA. You need to look at the actual valve events and other things effect it too like how open the throttle blades are. Usually I just add in using a vacuum reserve tank or vacuum pump and be done with the issue.
Nothing wrong in anything you said, but some changes in LSA would make many of those much more universal than they are now and not requiring a band aid of vacuum pump or can, and that is looking at all the events, not just LSA. Nothing magic there in any of the specs, but my guess is their target market doesn't know or care, just wants 100 bucks cheaper.
I would have to guess my question never got to Nutter, though, may try again for fun. I find it pretty hard to believe that unless Summit isn't stocking cores with enough spread, that it wouldn't be just a programming change, but such is life. I spec all my custom cams through Comp and Bullet, figured I'd do a test on a TFS 505 if they could accommodate the change, but no loss here
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Whether you can run a vacuum boost depends on not just LSA. You need to look at the actual valve events and other things effect it too like how open the throttle blades are. Usually I just add in using a vacuum reserve tank or vacuum pump and be done with the issue.
Nothing wrong in anything you said, but some changes in LSA would make many of those much more universal than they are now and not requiring a band aid of vacuum pump or can, and that is looking at all the events, not just LSA. Nothing magic there in any of the specs, but my guess is their target market doesn't know or care, just wants 100 bucks cheaper.
I would have to guess my question never got to Nutter, though, may try again for fun. I find it pretty hard to believe that unless Summit isn't stocking cores with enough spread, that it wouldn't be just a programming change, but such is life. I spec all my custom cams through Comp and Bullet, figured I'd do a test on a TFS 505 if they could accommodate the change, but no loss here
I don't this those running summit are car guys, more likely money guys.
Btw what LSA were you looking for? Most of those cams are on a 111 and one is on a 111.5 Really looking at them some are not that bad as far as overlap is concerned. A lot of I/E split on some too. Be interesting to see how they actually run, but as I said I'm not that interested.
As for vacuum pump being a band aid look at many modern cars and they use one, usually run off the cam. This is because they don't make enough vacuum. Keep in mind most vacuum boosters are designed to have at least 18" of vacuum. Yes you can get by with less, but I've found cars with 12"-14" vacuum can result in variation of boost. At least is something I've observed, but of course I tend to be sensitive to these types of things. Now a days I won't even do a vacuum booster when I can grab an electric booster from a Tesla and mod it to fit. Add an electric assist steering column from a Kia soul and no more power steering pump, hoses, and hydraulics to deal with, but I'm getting off topic here.
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I was speaking generally about shelf cams seeming to tend toward "idle sound" seems to be less of a market for one that sounds close to stock. We got "rattler" and "thumper" i propose a new line "sleeper" ... 8)
Doesn't "high performance" dictate a lumpy idle?
If we go back aways Isky ground everything on a 108 LSA and kept the intake and exhaust duration the same. Said it gave the best performance. Factory stuff like the 427 SFT cams had a bunch of duration and a 114 or 119 LSA. Now take the CJ. cam. That lobe was used on the 351C CJ, 390GT,428CJ,429CJ and a few others. Amazing how an OEM decided those lobes would work in all those different engines.
As I said you really have to look at value event and really really best is if you can look at the lift profile. You can have two cams with the same LSA and duration, but be a lot different.
I would say that high performance doesn't always dictate a nasty idle sound. You can have an absolute mild cam with a really good cylinder head and still make a lot of power.
It's not just the OEM that makes universal cams, all the cam companies have been doing that for decades. The same cam that's available for an FE is also available for a SBM or a Buick. I'm just thankful that we've made leaps and bounds in technology since the 60's. Unfortunately, a lot of guys still think a single pattern on a 108 is the ticket. Actually, most people focus way too much on the LSA period. It's like it's some magical number or something.
I had a guy email for a custom cam and said, "I don't care how you grind it, as long as it's on a 104 LSA".
Show me that you don't know anything without telling me that you don't know anything.
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Whether you can run a vacuum boost depends on not just LSA. You need to look at the actual valve events and other things effect it too like how open the throttle blades are. Usually I just add in using a vacuum reserve tank or vacuum pump and be done with the issue.
Nothing wrong in anything you said, but some changes in LSA would make many of those much more universal than they are now and not requiring a band aid of vacuum pump or can, and that is looking at all the events, not just LSA. Nothing magic there in any of the specs, but my guess is their target market doesn't know or care, just wants 100 bucks cheaper.
I would have to guess my question never got to Nutter, though, may try again for fun. I find it pretty hard to believe that unless Summit isn't stocking cores with enough spread, that it wouldn't be just a programming change, but such is life. I spec all my custom cams through Comp and Bullet, figured I'd do a test on a TFS 505 if they could accommodate the change, but no loss here
I don't this those running summit are car guys, more likely money guys.
Btw what LSA were you looking for? Most of those cams are on a 111 and one is on a 111.5 Really looking at them some are not that bad as far as overlap is concerned. A lot of I/E split on some too. Be interesting to see how they actually run, but as I said I'm not that interested.
As for vacuum pump being a band aid look at many modern cars and they use one, usually run off the cam. This is because they don't make enough vacuum. Keep in mind most vacuum boosters are designed to have at least 18" of vacuum. Yes you can get by with less, but I've found cars with 12"-14" vacuum can result in variation of boost. At least is something I've observed, but of course I tend to be sensitive to these types of things. Now a days I won't even do a vacuum booster when I can grab an electric booster from a Tesla and mod it to fit. Add an electric assist steering column from a Kia soul and no more power steering pump, hoses, and hydraulics to deal with, but I'm getting off topic here.
I change LSA based on overlap after lobe choices and what I need for customer and engine intent, not quite that simple, but easiest way to quickly explain it. It can range from 108 to 115 on most builds. However, on this one I wanted to see Summit's big cam spread to 114 or 115. Can't really say "can you revise your entire cam for me" but I did expect maybe an option to spread centers on a special order.
As far as being money guys, some of the best parts are coming from this company, glad to see them make a little. Trick Flow heads are owned by Summit Racing and their quality is fantastic and availability is good, although I sure wish they'd come back with their single 4 intake. As I said, I suspect either my question didn't get to where it needed to be or it's a stocking core problem, as you spread centers, the company has to stock semi-finiahed cores to meet that need, so maybe they don't see a need for the flexibility.
I am not against a can or electric pump if a customer wants it, but also have many on the street that are on resto cars that do not want any modern externals, and we can easily make 550 HP at well under 6000 and give them good vacuum by controlling overlap. When you do that, it makes for a very happy street car, and if the head supports it, can make some big power.
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Not withstanding Brents friends (Daniel?) findings, i agree with Ross and think that basically every one of them larger than the 8916 would probably be better on like a 113-115 and the jury is out on 8916.
The 8916 might be a nice street cruiser car/truck cam but you'd have to roll it back basically the entire advance for anything with compression and stock heads.
One of them is very very close (like within a degree) of the cam in my truck and i would not describe it as medium chop but at least i know how it would act (assuming i trust the numbers), still it would be better with more split and a wider lsa to keep the overlap in check....
Anyway. The guy i was talking to said he had e-mailed Nutter twice and not gotten a reply, so i guess answering any questions isn't in the marketing plan. In their other "pro" lines they have a wider selection so I guess there maybe "cough" "turbo" cams coming...
Custom is the answer if we want what we want...
At least they didn't off shore them, and choice is good...
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I change LSA based on overlap after lobe choices and what I need for customer and engine intent, not quite that simple, but easiest way to quickly explain it. It can range from 108 to 115 on most builds. However, on this one I wanted to see Summit's big cam spread to 114 or 115. Can't really say "can you revise your entire cam for me" but I did expect maybe an option to spread centers on a special order.
As far as being money guys, some of the best parts are coming from this company, glad to see them make a little. Trick Flow heads are owned by Summit Racing and their quality is fantastic and availability is good, although I sure wish they'd come back with their single 4 intake. As I said, I suspect either my question didn't get to where it needed to be or it's a stocking core problem, as you spread centers, the company has to stock semi-finiahed cores to meet that need, so maybe they don't see a need for the flexibility.
I am not against a can or electric pump if a customer wants it, but also have many on the street that are on resto cars that do not want any modern externals, and we can easily make 550 HP at well under 6000 and give them good vacuum by controlling overlap. When you do that, it makes for a very happy street car, and if the head supports it, can make some big power.
Yes I understand it is not LSA per se that you are looking, but rather it is the byproduct of the timing events. Reason you can do what you want is that you have good heads that don't need all that overlap to make power. Maybe if they made a cam intended as part of a package with the TFS heads be different. Regardless of what Summit provides it sure does not look like they are being run by car guys. Seems they are very focused on the money and that is not a bad thing if they make parts we can use, but you are a long way from talking to someone who has the interest you are looking for. Years ago when Joe Lunati ran Lunati cams you could get him on the phone and he would make it happen or tell you why you were wrong. Now Lunati doesn't even make cams. Honestly I would not be surprised if the guy who designed the cams was contracted and whoever wrote the CNC program was too and they are long gone. Probably have some guy that puts the blank in the machine and only knows how to load a program and hit the go button. Call me cynical, but its all about money.
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Not withstanding Brents friends (Daniel?) findings, i agree with Ross and think that basically every one of them larger than the 8916 would probably be better on like a 113-115 and the jury is out on 8916.
The 8916 might be a nice street cruiser car/truck cam but you'd have to roll it back basically the entire advance for anything with compression and stock heads.
One of them is very very close (like within a degree) of the cam in my truck and i would not describe it as medium chop but at least i know how it would act (assuming i trust the numbers), still it would be better with more split and a wider lsa to keep the overlap in check....
Anyway. The guy i was talking to said he had e-mailed Nutter twice and not gotten a reply, so i guess answering any questions isn't in the marketing plan. In their other "pro" lines they have a wider selection so I guess there maybe "cough" "turbo" cams coming...
Custom is the answer if we want what we want...
At least they didn't off shore them, and choice is good...
Don't take this the wrong way, but you cannot say with any certainty just by looking at the information on the website and a few of them don't have all that much overlap based on the seat timing. Those are some weird cams. Some of those lobes have a lot of lift for the duration. What Ross is doing is the same thing the OEM's been doing since the 60's which is take a long duration and then tighten up the LSA to kill the overlap ad get some manors.
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Widening the LSA would kill the overlap.
In addition, overlap at seat timing really doesn’t carry as much weight as .050” overlap.
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Doesn't "high performance" dictate a lumpy idle?
If we go back aways Isky ground everything on a 108 LSA and kept the intake and exhaust duration the same. Said it gave the best performance. Factory stuff like the 427 SFT cams had a bunch of duration and a 114 or 119 LSA. Now take the CJ. cam. That lobe was used on the 351C CJ, 390GT,428CJ,429CJ and a few others. Amazing how an OEM decided those lobes would work in all those different engines.
As I said you really have to look at value event and really really best is if you can look at the lift profile. You can have two cams with the same LSA and duration, but be a lot different.
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I would say that high performance doesn't always dictate a nasty idle sound. You can have an absolute mild cam with a really good cylinder head and still make a lot of power.
It's not just the OEM that makes universal cams, all the cam companies have been doing that for decades. The same cam that's available for an FE is also available for a SBM or a Buick. I'm just thankful that we've made leaps and bounds in technology since the 60's. Unfortunately, a lot of guys still think a single pattern on a 108 is the ticket. Actually, most people focus way too much on the LSA period. It's like it's some magical number or something.
I had a guy email for a custom cam and said, "I don't care how you grind it, as long as it's on a 104 LSA".
Show me that you don't know anything without telling me that you don't know anything.
[/quote]
LOL I was asking that "High performance cam" question tongue and cheek. Next we will start using terms like "3/4 race cam". The whole LSA and duration numbers thing is just a way to dumb it down and make joe sixpack feel he knows how to pick a cam. A little knowledge certainly can be dangerous. Yes the whole industry been build around a few lobes that work decent. Comp cams Magnum or high energy are examples. I'd say really it comes down to what your goals are and how picky you are. Of course I know guys who are just happy if their old car runs down the road and don't break down.
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Widening the LSA would kill the overlap.
In addition, overlap at seat timing really doesn’t carry as much weight as .050” overlap.
I thought I said that widening the LSA kills the overlap. Sorry I said tightening it, but that is what I meant. Yes .050" has more effect and .200" even more, but I haven't seen a cam with a lot of seat timing work as well as one with less, but your the cam guy so I'll just go back to doing my work and stop wasting time here.
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Widening the LSA would kill the overlap.
In addition, overlap at seat timing really doesn’t carry as much weight as .050” overlap.
I thought I said that widening the LSA kills the overlap. Sorry I said tightening it, but that is what I meant. Yes .050" has more effect and .200" even more, but I haven't seen a cam with a lot of seat timing work as well as one with less, but your the cam guy so I'll just go back to doing my work and stop wasting time here.
On some larger, more aggressive solid rollers, it will become more apparent. The seat duration will be short, but the .050" duration will be large.
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Don't take this the wrong way, but you cannot say with any certainty just by looking at the information on the website and a few of them don't have all that much overlap based on the seat timing. Those are some weird cams. Some of those lobes have a lot of lift for the duration. What Ross is doing is the same thing the OEM's been doing since the 60's which is take a long duration and then tighten up the LSA to kill the overlap ad get some manors.
We're good, it is a good discussion.
There's a chart that shows the .050 overlap of all of them and you can calculate the advertised from the events.
I find there are few things in the world that can be said with certainty and i often say to people "define better" or "best" so i guess I should say there's a very high probability those cams would idle better and have more vacuum (which are both positives imo) with wider LSA.
As far as the statement about rolling the 8916 back, at least in my ~10.3:1 445 and when the same engine was similar compression and a 390 it would spark knock the pistons into the oil pan at 65 degree intake close on any thing approaching pump gas and normal timing... I'm as certain of that as i am most anything,,, i strongly suspect the same story would apply to any stock headed FE with similar compression...
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The .050” overlap makes more of an impact.
I’ve had some really short advertised duration cams where the seat overlap was low but the .050” overlap was up there and they were completely radical sounding.
Over the past 2 years I’ve been in close contact and discussion with some really good lobe designers. What I’ve learned is that they emphasize .050” events over advertised events, look at valve events as a whole, and put little emphasis on LSA.