Vizard on 106* LSA vs 112* LSA in a BBC
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It wasn't that many years ago when Pro Stock 500 inch motors did use cams with a narrower LSA. I think Harold referenced a popular Pro Stock cam earlier in this thread.
Something happened a few years ago to change from narrower centers to wider centers. I think it all happened about the point where the engine builders started to get really good heads rather than using welded and epoxied stock casting but I'm not positive on that point. Darin might know but he doesn't seem to drift thru these posts very often.
Something happened a few years ago to change from narrower centers to wider centers. I think it all happened about the point where the engine builders started to get really good heads rather than using welded and epoxied stock casting but I'm not positive on that point. Darin might know but he doesn't seem to drift thru these posts very often.
Andy F.
AR Engineering
AR Engineering
Early Pro-Stock Cams
Andyf,
In the late 1960s, early 1970s, most Pro-Stocks were big blocks, without all the trick heads available now. Transmissions were 3-speed Turbo-Clutches, not Lencos.
The cams were SINGLE-PATTERN profiles on 108 LSA. One of the most popular was the General Kinetics 332B, 286 at .050, no info on .200 but max velocity was .0068"/*, and I have never designed a cam this slow....
And max lobe lift was .372", for .632" gross valve lift.
I later designed a cam to replace the 332B, and mine is the UF23, 322 at .020, 286 at .050, 195 at .200, peak velocity over .007"/*, and still .371" lobe lift. I offered it as a 332B replacement, single pattern on a 108, don't think I ever sold one.
It is in the exact family of the 288/296F5.......
UDHarold
In the late 1960s, early 1970s, most Pro-Stocks were big blocks, without all the trick heads available now. Transmissions were 3-speed Turbo-Clutches, not Lencos.
The cams were SINGLE-PATTERN profiles on 108 LSA. One of the most popular was the General Kinetics 332B, 286 at .050, no info on .200 but max velocity was .0068"/*, and I have never designed a cam this slow....
And max lobe lift was .372", for .632" gross valve lift.
I later designed a cam to replace the 332B, and mine is the UF23, 322 at .020, 286 at .050, 195 at .200, peak velocity over .007"/*, and still .371" lobe lift. I offered it as a 332B replacement, single pattern on a 108, don't think I ever sold one.
It is in the exact family of the 288/296F5.......
UDHarold
662-562-4933
brookshire@panola.com
brookshire@panola.com
Bores got bigger, strokes got shorter, and RPM got higherandyf wrote:It wasn't that many years ago when Pro Stock 500 inch motors did use cams with a narrower LSA. I think Harold referenced a popular Pro Stock cam earlier in this thread.
Something happened a few years ago to change from narrower centers to wider centers. I think it all happened about the point where the engine builders started to get really good heads rather than using welded and epoxied stock casting but I'm not positive on that point. Darin might know but he doesn't seem to drift thru these posts very often.
Mike Jones
Jones Cam Designs
Denver, NC
jonescams@bellsouth.net
http://www.jonescams.com
Jones Cam Designs' HotPass Vendors Forum: viewforum.php?f=44
(704)489-2449
Jones Cam Designs
Denver, NC
jonescams@bellsouth.net
http://www.jonescams.com
Jones Cam Designs' HotPass Vendors Forum: viewforum.php?f=44
(704)489-2449
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Re: Early Pro-Stock Cams
The heads were very poor which cause people to take steps to reduce displacement. In the mid '70's we built a low deck hemi using a semi finished 400 block with some help from Don Carlton who was running this same combination a 4.25" bore 3.38" stroke.UDHarold wrote:Andyf,
In the late 1960s, early 1970s, most Pro-Stocks were big blocks, without all the trick heads available now. Transmissions were 3-speed Turbo-Clutches, not Lencos.
The cams were SINGLE-PATTERN profiles on 108 LSA. One of the most popular was the General Kinetics 332B, 286 at .050, no info on .200 but max velocity was .0068"/*, and I have never designed a cam this slow....
And max lobe lift was .372", for .632" gross valve lift.
I later designed a cam to replace the 332B, and mine is the UF23, 322 at .020, 286 at .050, 195 at .200, peak velocity over .007"/*, and still .371" lobe lift. I offered it as a 332B replacement, single pattern on a 108, don't think I ever sold one.
It is in the exact family of the 288/296F5.......
UDHarold
Re: Vizard on 106* LSA vs 112* LSA in a BBC
To the OP, he is using what is correct for the engine at hand.
Please Note!
THE ABOVE POST IN NO WAY REFLECTS THE VIEWS OF SPEED TALK OR IT'S MEMBERS AND SHOULD BE VIEWED AS ENTERTAINMENT ONLY...Thanks, The Management!
THE ABOVE POST IN NO WAY REFLECTS THE VIEWS OF SPEED TALK OR IT'S MEMBERS AND SHOULD BE VIEWED AS ENTERTAINMENT ONLY...Thanks, The Management!
Re: Vizard on 106* LSA vs 112* LSA in a BBC
Wow, talk about a thread back from the dead! Risen from the grave after five years and four months!
Felix, qui potuit rerum cognscere causas.
Happy is he who can discover the cause of things.
Happy is he who can discover the cause of things.
Re: Vizard on 106* LSA vs 112* LSA in a BBC
It's getting nearer to Holloween when all things dead rise from their graves...MadBill wrote:Wow, talk about a thread back from the dead! Risen from the grave after five years and four months!
Honored to be a member of the Luxemburg Speedway Hall of Fame Class of 2019
Re: Vizard on 106* LSA vs 112* LSA in a BBC
Good things never die!
You can think Google for that.
You can think Google for that.
Please Note!
THE ABOVE POST IN NO WAY REFLECTS THE VIEWS OF SPEED TALK OR IT'S MEMBERS AND SHOULD BE VIEWED AS ENTERTAINMENT ONLY...Thanks, The Management!
THE ABOVE POST IN NO WAY REFLECTS THE VIEWS OF SPEED TALK OR IT'S MEMBERS AND SHOULD BE VIEWED AS ENTERTAINMENT ONLY...Thanks, The Management!
Re: LSA
That makes me feel better about the lsa thingy, I have cam specs from DV's Cam Masters that range from 105 to 118 depending on engine and application.UDHarold wrote:My opinion is that you should buy whatever Dave Vizard recommends, because you probably deserve it.......
Tell your cam man what LSA you want, and he will grind it for you.
This way, your car will run its' fastest.
However, I recommend everywhere from 107 to 118, just depending.
UDHarold
Please Note!
THE ABOVE POST IN NO WAY REFLECTS THE VIEWS OF SPEED TALK OR IT'S MEMBERS AND SHOULD BE VIEWED AS ENTERTAINMENT ONLY...Thanks, The Management!
THE ABOVE POST IN NO WAY REFLECTS THE VIEWS OF SPEED TALK OR IT'S MEMBERS AND SHOULD BE VIEWED AS ENTERTAINMENT ONLY...Thanks, The Management!
Re: Vizard on 106* LSA vs 112* LSA in a BBC
In the mid '70's we built a low deck hemi using a semi finished 400 block with some help from Don Carlton who was running this same combination a 4.25" bore 3.38" stroke.
I built one using Stage V heads
I was thinking building one with OEM heads would make a tough 370 Bonneville motor for that new class
But then someone would build a 332 crank in a 427 SOHC FORD
I built one using Stage V heads
I was thinking building one with OEM heads would make a tough 370 Bonneville motor for that new class
But then someone would build a 332 crank in a 427 SOHC FORD
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Re: Vizard on 106* LSA vs 112* LSA in a BBC
GARY C wrote:To the OP, he is using what is correct for the engine at hand.
I think Gary C is Vizards publicist! LOL
Re: Vizard on 106* LSA vs 112* LSA in a BBC
Warp Speed wrote:GARY C wrote:To the OP, he is using what is correct for the engine at hand.
I think Gary C is Vizards publicist! LOL
I'm guessing a paid 540 rat stroker................
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Re: Vizard on 106* LSA vs 112* LSA in a BBC
Isn't LSA very dependent on flow between intake and exhaust during overlap?
Hemi and Canted,twisted valve engines flow through easier than parallel valve engines.
And as compression rises the more difficult it is to get room for a narrow LSA.
How do you get 15:1+ compression on a big bore short stroke P/S engine with an LSA under 112 degrees?
Erland
Hemi and Canted,twisted valve engines flow through easier than parallel valve engines.
And as compression rises the more difficult it is to get room for a narrow LSA.
How do you get 15:1+ compression on a big bore short stroke P/S engine with an LSA under 112 degrees?
Erland
Re: Vizard on 106* LSA vs 112* LSA in a BBC
I don't think you'd want to, would you?Erland Cox wrote: How do you get 15:1+ compression on a big bore short stroke P/S engine with an LSA under 112 degrees?
Erland
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Re: Vizard on 106* LSA vs 112* LSA in a BBC
Keep the "pour volume" @ TDC at 60.3cc's . Small bore long stroke or big bore short stroke , the number hardly changes as long as it's 500 inches and 8 cylinders. yes it is tougher ( or impossible) on large cc heads , but P/S heads aren't 118cc chambers.RevTheory wrote:I don't think you'd want to, would you?Erland Cox wrote: How do you get 15:1+ compression on a big bore short stroke P/S engine with an LSA under 112 degrees?
Erland