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Re: 128 my take, anybody see it like this ?
Posted: Wed Sep 21, 2022 10:50 pm
by skinny z
rebelyell wrote: ↑Wed Sep 21, 2022 10:17 pm
In the larger view, it seems "128" is applicable to only a very narrow range of strictly defined applications. I'd hoped for more.
This is true although apparently the author has workarounds for those outside the "box".
Re: 128 my take, anybody see it like this ?
Posted: Wed Sep 21, 2022 11:09 pm
by digger
hoffman900 wrote: ↑Wed Sep 21, 2022 3:06 pm
F-BIRD'88 wrote: ↑Wed Sep 21, 2022 3:04 pm
Orr89rocz wrote: ↑Wed Sep 21, 2022 2:17 pm
It’s unfortunate the catalog cams never seem to come in under 110 lsa. Can find some under that but much more limited than the 110-114 lsa cams out there. So sucks the program gives you 104-108 lsa stuff and you still have to get it custom ground if there are cores available for that tight lobe separation
There are lots of catalog cams that are 104 105 and 106 and 108 LSA.. You just have to look.
Check out the Isky cams stuff. These cams ALWAYS work well.
Check out the Linati / UDHAROLD "Street/Strip" cams series and the tight lash stuff.
Most of those are directed at circle track and road racers, which centerlines in those areas work great for. They are not very efficient under 3000rpm though.
Like I have said. Vizard’s formula isn’t doing anything special. He data fit results of engines he tested on the dyno to make good torque / ci for those applications. The problem is there is more to a cam than dyno results and no one on the street needs best power between 3500-7000rpm at WOT.
i'd rather a cam that has better power 3500-7000 than 5500-7000 on a street engine
Re: 128 my take, anybody see it like this ?
Posted: Thu Sep 22, 2022 12:34 am
by F-BIRD'88
The 110 and 112 LSA catalog cams are just right for you guys.. You are the target market for these.
Re: 128 my take, anybody see it like this ?
Posted: Thu Sep 22, 2022 1:09 am
by Tom68
juuhanaa wrote: ↑Wed Sep 21, 2022 2:53 pm
hmmmm
307 601.png
Cool right, and I have a 307 laying around to.
But how do you pick a cam from that if it only gives 20 thou numbers ? I'm sure 20 thou is an excellent reference point but it's not a number that everybody has a feel for like 50, 006 and 004. Also takes more research to get a suitable cam.
Don't get me wrong, any engine I play with has the cam fully mapped. I know what I have and I know what I want and when I don't, I email the CamKing.
20220922_152100.jpg
Re: 128 my take, anybody see it like this ?
Posted: Thu Sep 22, 2022 4:04 am
by Geoff2
LSA/LDA/LCA all refer to the same thing.
I find it amusing that the DV bashers never give their dyno results or offer any proof that their cam selection method works any better. Is it just jealousy?
And it is nonsense to say LSA is not meaningful/irrelevant. It tells you where the valves are at max lift in crank degrees. A 106 LSA tells you the int valve is at max lift @ 106* ATDC; the exh valve is at 106* BTDC. This factors into piston acceleration & piston position relative to stroke.
I see a LOT more cams now with tighter LSAs than I did 30+ yrs ago. One cam grinder in the 70s who was ahead of the curve was Crower. He had a couple of street grinds for 440 Mopars that were on 105 LSAs.
Re: 128 my take, anybody see it like this ?
Posted: Thu Sep 22, 2022 4:50 am
by digger
All methods for calculating cam specs are wrong, it’s just some are less wrong than others
Re: 128 my take, anybody see it like this ?
Posted: Thu Sep 22, 2022 5:27 am
by juuhanaa
But how do you pick a cam from that if it only gives 20 thou numbers ?
Tom, as for the program, i look the big picture and compare it to my game plan. The program comes with a database, so you can pick a cam and other parts from the "cataloque", but i can't remember is the 20 thou numbers used there. Im not familiar with the v8 stuff, but i think they are exiting to study with and i picked the cam, because i got a good deal and it is a challenge to build heads and everything around a cam.
I have only few heads and intake manifold on my junk pile, but i dont have 307 laying around. There is -91 tbi caprise for sale locally though
I dont know.. A good friend of mine has a chevy pick up, maybe i can figure something.
Re: 128 my take, anybody see it like this ?
Posted: Thu Sep 22, 2022 8:30 am
by skinny z
F-BIRD'88 wrote: ↑Thu Sep 22, 2022 12:34 am
The 110 and 112 LSA catalog cams are just right for you guys.. You are the target market for these.
Who are YOU guys...?
Re: 128 my take, anybody see it like this ?
Posted: Thu Sep 22, 2022 8:31 am
by skinny z
Tom68 wrote: ↑Thu Sep 22, 2022 1:09 am
juuhanaa wrote: ↑Wed Sep 21, 2022 2:53 pm
hmmmm
307 601.png
Cool right, and I have a 307 laying around to.
But how do you pick a cam from that if it only gives 20 thou numbers ? I'm sure 20 thou is an excellent reference point but it's not a number that everybody has a feel for like 50, 006 and 004. Also takes more research to get a suitable cam.
Don't get me wrong, any engine I play with has the cam fully mapped. I know what I have and I know what I want and when I don't, I email the CamKing.
20220922_152100.jpg
128 refers to seat timing. It would be up to the end user to decide on lobe intensity.
Or CamKing.
Re: 128 my take, anybody see it like this ?
Posted: Thu Sep 22, 2022 9:30 am
by Stan Weiss
Tom68 wrote: ↑Thu Sep 22, 2022 1:09 am
Cool right, and I have a 307 laying around to.
But how do you pick a cam from that if it only gives 20 thou numbers ? I'm sure 20 thou is an excellent reference point but it's not a number that everybody has a feel for like 50, 006 and 004. Also takes more research to get a suitable cam.
Don't get me wrong, any engine I play with has the cam fully mapped. I know what I have and I know what I want and when I don't, I email the CamKing.
He is looking at a
solid roller tappet. Actually if you look at most cam company's master cam lists they rate solid cams @ 0.020" TMC will use 0.006" for a hydraulic cam.
Stan
Re: 128 my take, anybody see it like this ?
Posted: Thu Sep 22, 2022 10:03 am
by CamKing
355" SBC
10:1 with ported 492 heads, Performer RPM, and Holley 600.
RPM---TQ--BHP
3200--436--266
3400--443--287
3600--445--305
3800--444--321
4000--443--337
4200--440--352
4400--440--368
4600--441--386
4800--441--403
5000--432--411
5200--422--418
5400--412--423
5600--400--426
The cam is 216/220, on a 112 LSA, and 108 ICL
Re: 128 my take, anybody see it like this ?
Posted: Thu Sep 22, 2022 10:32 am
by Bigchief632
I fixed/freshened a Edelbrock 350 crate engine some years back. Cam went flat. Honed, rings, bearings, polish crank, new gaskets etc. Edelbrock, sent him the "rolling thunder" hydraulic roller upgrade, cam, lifters, spider, gaskets, pushrods, for like cost, it was MANY years after the warranty, it was like $300 or something, they didn't have to do it. I did a valve job and re surface on heads only, it made 440 and 440, and pulled to 6500. That cam is 234-238 .535/.535 or something like that for lift on a 112+5. It idled mild, and and had really good power for the pistons .025 in the hole and only 9.5:1. I wonder what it would have made with improved "quench"
maybe 445? lol, from the half point of compression gain.
Re: 128 my take, anybody see it like this ?
Posted: Thu Sep 22, 2022 10:38 am
by skinny z
CamKing wrote: ↑Thu Sep 22, 2022 10:03 am
355" SBC
10:1 with ported 492 heads, Performer RPM, and Holley 600.
RPM---TQ--BHP
3200--436--266
3400--443--287
3600--445--305
3800--444--321
4000--443--337
4200--440--352
4400--440--368
4600--441--386
4800--441--403
5000--432--411
5200--422--418
5400--412--423
5600--400--426
The cam is 216/220, on a 112 LSA, and 108 ICL
Your lobes Mike ( I would think yes)?
Which ones?
Re: 128 my take, anybody see it like this ?
Posted: Thu Sep 22, 2022 11:04 am
by Orr89rocz
CamKing wrote: ↑Thu Sep 22, 2022 10:03 am
355" SBC
10:1 with ported 492 heads, Performer RPM, and Holley 600.
RPM---TQ--BHP
3200--436--266
3400--443--287
3600--445--305
3800--444--321
4000--443--337
4200--440--352
4400--440--368
4600--441--386
4800--441--403
5000--432--411
5200--422--418
5400--412--423
5600--400--426
The cam is 216/220, on a 112 LSA, and 108 ICL
Its almost like the right engine build, with a good induction package will dictate power curve characteristics more so than what lsa you have.
Re: 128 my take, anybody see it like this ?
Posted: Thu Sep 22, 2022 11:08 am
by ClassAct
hoffman900 wrote: ↑Wed Sep 21, 2022 2:43 pm
Orr89rocz wrote: ↑Wed Sep 21, 2022 2:17 pm
F-BIRD'88 wrote: ↑Wed Sep 21, 2022 10:33 am
When you read DV's books and select the overlap as per the overlap pie chart for the intended application RPM and build level. and apply the 128 formula for that engine you get a camshaft duration. (within a workable relevent range)
Mostly biased for a single pattern camshaft.
You can then tweek things a bit if you want a dual pattern cam. This tends to widen the LSA a hair. It doesn't have to but...- it tends to-. And then you can tweek the installed position "advance" .. Don't be timid to play with this +/-.
And as DV said in his comments a Dual Plane intake manifold can tolerate a slight widening of the LSA a hair. VS what a single plane manifold is going to favour to make good torque.
It is intended as a guide for the end user to get a high torque per cid street strip perf engine.
A better but simple method VS just selecting from the catalog page.
It’s unfortunate the catalog cams never seem to come in under 110 lsa. Can find some under that but much more limited than the 110-114 lsa cams out there. So sucks the program gives you 104-108 lsa stuff and you still have to get it custom ground if there are cores available for that tight lobe separation
That’s because catalog cams are designed and sold to be mostly dummy proof / easy to tune / easy to drive around for what constitutes the majority of their sales. Everyone keeps bringing up dyno sheets that start at 3500rpm and I bet for 95% of those catalogue cam buyers they spend 95%+ of their time below that.
A cam with durations around 260* at .050” + and ground 104-106 (straight up) is going to be too much for a lot of those people.
Even someone like Harold Brookshire said as much:
UDHarold wrote: ↑Tue Apr 28, 2009 11:31 am
Does anyone have a list of cam companies offering BBC cams on such tight LSAs? Or of BBC cams made with such LSAs?
I know at UltraDyne, from 1980 on, two of our most popular BBC cams, the BB288/296F7 and the BB286/300R7, were extremely popular ground on 107 LSAs.
However, they were almost unstreetable, at least for the average guy.....
UDHarold
Harold NAILED it. Most guys think tuning a carb means changing the jets and setting power valve timing at half idle vacuum and sending it.
If you are willing to learn to tune (we never stop learning do we??) you can easily get a “tight” LSA very driveable. Like I said, my wife drives my car. She’s scared of it and thinks she can break it but she baby’s it around and has no issues.
Of course, the tunnel ram goes on this winter so we will see what she thinks of that!