Is there a better cam for me?

[cj's mopar]

We are looking to experiment with the David Visards 128 formula.
He's very adamant about.
He likes tighter lobe separation angles and smaller duration cams for tourqe.
He claims he has gotten 1.4 pounds per CID .by doing this .
What if I ground the cam above like this
230 236 at .50 on a 104 or 105.
The formula says my motor wants
104.8.

 

[Curiousyellow71]

We are looking to experiment with the David Visards 128 formula.
He's very adamant about.
He likes tighter lobe separation angles and smaller duration cams for tourqe.
He claims he has gotten 1.4 pounds per CID .by doing this .
What if I ground the cam above like this
230 236 at .50 on a 104 or 105.
The formula says my motor wants
104.8.

I think you need to do more research. LSA is always narrower for a single pattern vs split pattern. He may be using a formula for a single pattern, not the same as a split pattern.

 

[cj's mopar]

Okay thank you for that , he doesn't really mention the pattern
His focus is on the intake side of the cam .and the LSA in relationship to his overlap chart .

 

[Curiousyellow71]

Okay thank you for that , he doesn't really mention the pattern
His focus is on the intake side of the cam .and the LSA in relationship to his overlap chart .

Are you referring to vizard or your engine builder?

 

[cj's mopar]

David Vizard

 

[Curiousyellow71]

Vizards 128 rule is for a single pattern cam. It is still good information but you need to consider how lsa and overlap is changed w the dual pattern. Dual pattern you will have to add to the LSA if you are looking for similar timing events as the the single pattern. You don't usually see single patterns with wide LSA's. A single pattern has the same overlap as a dual pattern cam w a wider LSA because of the larger exhaust.

 

[Geoff 2]

CJ. Smart move using 128.
There is a you tube video by the 'Cattle Dog Garage' [ 30 min video, NOT 1 hr video ]. Sorry, do not know how to link it. Validates the 128 rule.

Here is another LSA test, looooon before 128 was a gleam in anybody's eye....

 

[cj's mopar]

Geoff ,
Thanks for posting this .
I am leaning on giving this a try and ordering a custom ground cam for my Engine .
The chart does show what most people think the 110 does idle easer but at those idle speeds I beg to say that the carb was an out of the box type with the idle speed to transfer slot relationship way off.
This is very common back in the day.
These testers did not have time to mod the carb.
I feel confident with my manual brake stick shift car I can get the idle down to 1000 or 950 with some carb turning.
So sounds doable.
Sure would like to hear from someone who actually has done that and ordered a cam on 104 LSA and hear their experiences.

 

[cj's mopar]

What the hell is this guy talking about then?

 

[RemCharger]

The whole concept has to make you think though..... all of these cam companies should be just making " custom cams" because all of the cams they already designed are junk? I'm surprised after 50 years they haven't figured out what works.

 

[Curiousyellow71]

I can barely read it..post doesnt mention durations, but anyone that's says they are a happy with a 440 with 906 heads pulling great "above" 7500rpm w a cam on 104 installed at 99 is on another level. As to what level I will let you decide.Lol

It's really very little more to do a custom with roller grinds. They are already expensive.

 

[Geoff 2]

Remcharger,
Crane cams DID figure it out [ post #71 ]. After DV tested 19,000+ cam combinations fior Crane, there were a LOT more cams in later catalogs ground with 106-108 LSAs.....than in prevois catalogs.

 

[Geoff 2]

A lot of nonsense has been written about tight LSA cams, not revving out or droping off at high rpms. 98 LSA is pretty tight.....

Jon Kaase won the EMC with a cam ground on 98 LSA, 92 ICL. It made 663 hp & dropped a mere 9 hp past peak hp.

 

[PROSTOCKTOM]

Even if the cam and timing chain were machined perfect a chain stretches and you lose several degrees of timing. If they are off you could be 6-8 degrees off. You stated that it's snappy, so it might not be to off to much, but I always advocate using a degree wheel and adding in 2-4 degrees extra depending on what level of timing chain you're using. If it runs good now I would just replace the cam with the next step up that adds another 6 degrees. You have decent amount of rear gear, but a Super Bee is not a lite car and 6 more degrees with definitely change things for more upper end.

Tom

 

[Curiousyellow71]

Even if the cam and timing chain were machined perfect a chain stretches and you lose several degrees of timing. If they are off you could be 6-8 degrees off. You stated that it's snappy, so it might not be to off to much, but I always advocate using a degree wheel and adding in 2-4 degrees extra depending on what level of timing chain you're using. If it runs good now I would just replace the cam with the next step up that adds another 6 degrees. You have decent amount of rear gear, but a Super Bee is not a lite car and 6 more degrees with definitely change things for more upper end.

Tom

We checked a cheap double roller after 10k. It had stretched 9 degrees.
To the op:
Below is comparison on a sbc of LSA's on a dyno. I don't recall where it came from, and was hesitant to post because the cam/engine specs needed to be mentioned and it is not a 440... but the affect on vacuum is also interesting. We run more compression with wider LSA's, and that is another subject. They did not do a 104 in this test. But it was not getting better.

 

[RemCharger]

Is this thread more about trips down memory lane and bum broomsticks from the 70s??

 

[Curiousyellow71]

Is this thread more about trips down memory lane and bum broomsticks from the 70s??

I'll take...
Bum broomsticks from the 70s for $500.Lol

 

[PROSTOCKTOM]

Hi everyone,
I been spending Alot of time reading and looking at cam lobe charts .
I am looking for best possible cam for my combination.
What do you guys think of this Hyd roller cam.
230/236 at .050
286/290 AVD
564/570 lift
On 108 LSA
Engine 10.8 compression 450 CID.
Stealth heads with valve job and 26120 beehive springs lightweight retainers.
1.5 crain gold rockers.
4 Speed 391 gears
Six pack carbs
TTI headers 2.5 exhaust with American thunder mufflers.
Electronic Ignition.
Holley 140 black fuel pump
Car 69 Super Bee with lift off hood.
Let's hear the yeas and nays !

For what it's worth I have a Comp Cam Xtreme Energy XR274R Solid Roller in my 499" RB 236/242 @ .050" .564"/ .570" and it runs really well on the street.

I think you'll be very happy with the profile you listed above since you have 50 cubic inches less and a heavy car.

Tom

 

[cj's mopar]

Hello all ,
I been in garage degreing my 228/236 cam to see where icl is at
We are in dot to dot straight up and ICL
Is coming to 104.5.
So there goes the therroy that it was not installed correctly for the cam card
Hughes wanted it in at 107
If I advanced it now we will be at 100.
Not sure but I might trying it out before I replace the cam.
DV's formula says I need a cam ground on a 104.8 LSA and with a street strip chosen Overlap from the chart .
Puts me at 289 intake duration is what this motor would want .
I am looking at comp lobes
At this
236/244 at .050 570/575 lift ground on 104 gives me roughly 89 overlap witch might be.slightly high with the summit calculator.
My current cam at 110 work out to 66 overlap.
So that is dead middle of the street performance on the chart .
This would make sense I want to be dead middle of street strip at about 80. OlL

 

[PRHeads]

You may want to check with a few cam grinders to see if they have a blank that will actually facilitate the lift and lsa you’re proposing.

Roller cores have a fairly small lift/lsa window that they can be used for.
A Low-ish lift and tight lsa roller core for a BBM might be tough to come by.