All I know is my 414 small block with 106 lsa oval track cam makes me giggle when I put my foot in to it. Killer idle too. Now I want nothing else! Torque was at least 450ft;lbs from 3000 to about 5400. It's only about 9.3 comp.
Does this prove David Vizard's 128 lsa formula ?
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All you need is a 3500 rpm convertor or side step the clutch and hold on tight.
Yes and no. It really doesn’t matter - Why?
You have seen here, read everywhere and been told over and over again to do what????
Degree your cam! Then you know it’s right.
My MP .590 needed a 1* adjustment. Oddly enough, that was the only cam key I had on hand.
I get that as long as it's degree'd it should be fine... i just worry about everything and being 6* off was just bothering me, wanted to know if it is a known thing that happens is all
I recently degreed a cam with a cloyes timing set.I get that as long as it's degree'd it should be fine... i just worry about everything and being 6* off was just bothering me, wanted to know if it is a known thing that happens is all
It was of 8 degrees retarded Dot to Dot.
I called cloyes, the guy said they are aware of some sets that were marked and keyed wrong.
He would have replaced it but I just made it work ignoring the advance/retard marks.
(It actually took putting the crank gear on one of the retard keyways to get the 4 degree advance centerline I wanted.)
Just one example of why you need to degree any cam.
Do not trust just lining up the dots.
Stack Tolerances between the cam and timing set can change a lot and
QC isn't very good these days...
Newbomb Turk
Well-Known Member
Probably not. In-line wedge heads SUCK at overlap and that is what matters. You get overlap right and you can get VE’s in the 110-115 range. That makes power.
Of course, I’ve been told here that horsepower doesn’t matter and 300 is plenty so this is all mental masturbation.
I might add that that thinking is bullshit. In 44 plus years I have never had a customer say to me “I want less horsepower” unless it was an engine that was built for one thing and they want to use it differently.
But that's not how DV sells it, he always brings up the 1% of engine builders that gets 138 + lbs-ft per cid and how he's in the 1 percent largely to due to his system. I have no problem with peeps using for ball park, I would use it for ball park, and maybe it does get close to optimal but there hasn't been any evidence that I've seen other than narrower lsa generally gives more mid range torque.
Plus it only really gives lsa spec and you suppose to guess the overlap you need and figure duration from there, for the system to be complete he should have a way to calculate needed overlap.
I'm not trying to discredit DV I would like for his formula to be true or at least close enough, but until I see evidence or strong indications that it is I'm gonna take it with a gain of salt. But overall I like DV approach to building power for the street.
I think what people mean by plenty, is for a good percent peeps a well setup 300 hp A body will satisfy,
For some a stock /6 is all they need, and others need sky is the limit power. And some will have 3 or so cars to cover each.
Newbomb Turk
Well-Known Member
I pulled my Larry Shepard book and my 2005 PAW catalog books to do some LSA (Centerline) comparisons based upon this discussion thread. It seems that the trend is to use a 110-112 LSA for street or mild competition and a 108-106 for maximum or modified competition.
As was previously mentioned, this is old knowledge that is still valid today for these type of engines.
As was previously mentioned, this is old knowledge that is still valid today for these type of engines.
Dang! Why can’t I increase the resolution of the photos to get them to be readable when enlarging them?
Never said people would build a 300 hp engine then would want to detune it for less.
Yep, that page needs to be scanned.
What DV trying to push is that you always run the tighter lsa and sacrifice duration instead for driveability which I think has merit, so eg.. Instead of say 276 cam on 112 run a 268 on 108.
Newbomb Turk
Well-Known Member
Of course not. No one wants less power. Ever. No decent engine builder would ever claim a customer wanted less power. Even the street guys.
So when guys come on here and jabber on about too much power I just write it off as them being ignorant of what engine builders deal with.
I have a customer coming to the dyno soon. I spec’d his engine. I gave him what he wanted. And he’s way above his pay grade with it.
Hopefully in 2 or 3 days on the dyno he learns things.
Anyways, here's a PDF scan of the sheet that I had posted earlier.
It seems that the FABO software reduces all images to a low resolution to save space on the servers.
It seems that the FABO software reduces all images to a low resolution to save space on the servers.
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I trust what DV has to say, 10’s of 1000’s dyno pulls on the SBC went into writing the 128 formula.
Then again Warren Johnson has said “the only thing wrong with a dyno is you can’t put tires on it and make a hit”.
After seeing pictures of his shop in HotRod years back, and one bench in particular that looked like there were 100 cams on top of it, drag strip testing cam changes looks to be the only way to get top performance.
And we all know how he dominated pro stock for years.
So unless you are willing do all those test hits with different cam grinds, DV’s formula is the best way forward and that is where I have faith. To me as a novice, that is the logical path forward.
Then again Warren Johnson has said “the only thing wrong with a dyno is you can’t put tires on it and make a hit”.
After seeing pictures of his shop in HotRod years back, and one bench in particular that looked like there were 100 cams on top of it, drag strip testing cam changes looks to be the only way to get top performance.
And we all know how he dominated pro stock for years.
So unless you are willing do all those test hits with different cam grinds, DV’s formula is the best way forward and that is where I have faith. To me as a novice, that is the logical path forward.
Sounds like your good to go.I get that as long as it's degree'd it should be fine... i just worry about everything and being 6* off was just bothering me, wanted to know if it is a known thing that happens is all
Exactly!
The 110/112 is fine for street drivers not concerned with anything but a nice easy driver. 112 is really good for that. Now if your throwing away torque due to the LSA being wider than optimal but like the smoothness for your car and driving style, then it all doesn’t really matter.
@273 DV supplies graphs and testimony. He has more time in the dyno rooms **** house than you have been alive. If his writings of what he did are t good enough for you then please by all means start dnyo testing your own engines and camshafts.
Let us know how it works out.
You can stand on the highest mountaintop and preach it, but some guys are gonna stab it in "dot to dot" come hell or high water and think there's nothing wrong. I cannot count the number of threads on here asking for help and the guy just turns around and does the exact opposite of what twenty or more people are advising him to do.....and he ASKED for help. lol
I’m nether but wonder about those extremes.
But yet, people come here, seek help from the internet strangers, take the advice and are happy from these no face, no name, no notoriety people based on there claims that they “Know” or “I’ve been there and done that, trust me, it’s the way to go.”
Since your doubting and discrediting DV. What’s your argument against his claims?
Where is your data for proof?
What is your history in this area and expertise level that your going to claim?
You can doubt him. But to discredit him based on… what now?
This isn’t me being a DV flag waving supporter saying “How dare you!” It’s me wondering about you and your discrediting words against him when you have been here for years asking questions and getting things not just wrong but stupendously backwards!
I'm not looking to discredit him, I'd be happy if his system works, I just haven't seem any glaring proof and the evidence against isn't concrete cause none of the dyno test are really setup to put his theory to the test, but what test that are on different lsa show little evidence being off a few degrees results in 30,40,50 etc.. lbs-ft loss.
Say Eg. If 108 is calculated as optimal then every degree in either direction should show huge loses, plus going wider than 108 is generally given that there will be loses so not much proof if 110/112 has less torque, but if going tighter than recommended like 104/106 don't lose torque but still gains is 108 optimal then?
So if 112 has least torque and 104 has most and the recommended 108 is in the middle is that really calculating optimal especially if the torque is less than 20 lbs-ft between each (104 vs 108 & 108 vs 112) and being 4 degrees off should be considered way off.
That video the guy's point was to prove DV and I'm saying none of the dyno test he showed gave any real proof, to me it put doubt on it.
I have a functioning brain and able to process information.
That's how I see lot of the **** you say
I watched this guy's video, I was neither for or against, but his point was to prove DV and him right and I didn't really see any evidence that did that for me, seemed like the opposite and gave me doubt so I posted to get your guy's take on it. Not some grand effort to prove DV wrong and the main push back I'm getting is of course DV right how dare you question him lol If that's the best argument for, then of course I'm gonna still have doubt.
junkyardhero
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building on this, @273 how many cams have you swapped, as in a back to back or even in a 2bbl to 4bbl saturday thrash session and then ran?
iirc, you had a crate motor that you did or were going to change the cam?
i ask this not as a knock against you, but out of genuine curiosity. you seem all about the cam theory but has any of that been put into practice?
No problem I admit I don't have tons performance experience that's Rumbles hole card on me, I worked at my dads garage for a number of years as a child/teen until he lost it cause of health, never done a full engine build mainly 340/360 top ends swaps on 318's most my cars were /6, done things like put a V8 in a dodge Laser got it to a rolling chassis with a 300z rear end had to get rid of it when my dad lost the shop. Help my cousin with his stock car. I mainly know from pouring over every build I could find from like 8 years old and my Uncle did a lot of engine builds when I was young he was into street racing anything I didn't get he'd would help, I had a pretty good understanding before I could drive. And I'm 50 now so yes most my knowledge is from reading.
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