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By Hollow Head - 18 Years Ago
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Where can we get true specifications about Y-Block cams? I have a CABX 28 camshaft from '62 - '64 truck block and I have two ways to go. To keep it stock because it is like new or to take it to the local machine shop to be regrind for more lift. All information is welcome about any cam. 
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By pegleg - 18 Years Ago
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Hollow, I doubt if the local machine shop will be able to regrind your cam. Mummert can supply you with something, and I believe he has the specs for stock cams. It'll depend on what and how you intend to use the truck. Frank
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By Hollow Head - 18 Years Ago
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Well... they made one last year from '56 camshaft by the Mummerts Y-265S specs and it works fine by the owner of one '59 Edsel here in Finland. GT-motor, The machine shop, has done regrinds for years for Finnish rally and race drivers so I know that they can do. And the price, you can't belive, 100 euros ( 130 dollars) and that included grinding of the groove to the center bearing surface  And phosphate coating for the lobes .
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By Hollow Head - 18 Years Ago
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And Frank, It'll be in our Hollow Machine rod and it's new Twin Turbo setup. So, I quess it won't need more lift. Just raising the boost. I've heard that Turbo engines doesn't need a "big" camshaft. True? 
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By LordMrFord - 18 Years Ago
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Quoted from turbomustangs forum...
http://www.turbomustangs.com/tmfaq.php
"Which cam should I run?
The stock cam will support enough hp to crack the stock block in half and provide superb driveability. There is really no reason to change cams unless you want to make big time power."
I think new(twenty years old?)Mustang's cam is not too far from stock Y-block cam.
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By Hollow Head - 18 Years Ago
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Ok. I was at my garage a moment ago and took some measurements out of that CABX-28 camshaft. These are taken from the lobes, so we are talking about cam lift, not valve lift. Stock cam lobe is about 1.6 inch high when the basic circle is about 1.3 inch wide. At the bottom of the lobe there is extra material for about .161 inch that can be grind away to get more lift. Stock lobe in that camshaft has about .236 inch cam lift. When we calculate these two together we end up to .397 cam lift  . How much is then the valve lift with 1.43 rocker arm ratio? Or with 1.54 ratio? Just wondering.... BTW The cost for that grind in Finland was 150 euros. I had to check that from the owner of that Edsel. Sorry about false information. Also he stated that that camshaft has about .433 inches of lift measured from the valve.
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By Hollow Head - 18 Years Ago
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And the answer is... .568 inch with 1.43 ratio and .611 inch with 1.54 ratio. Quite awesome . Lunati has great sites... http://www.holley.com/data/TechService/Technical/Understanding%20Camshafts.pdf
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By pegleg - 18 Years Ago
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Hollow. That's some machine shop. I've never seen one in the US with a cam grinder. The theory on Turbo cams is to not allow to much overlap, nowadays they spec it with the "lobe centers". Keeps the boost from allowing the mixture to blow right out the exhaust valve. That's an awful lot of lift for a Y. Best run real good springs and check the piston to vale clearance, could get close. Frank
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By PF Arcand - 18 Years Ago
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H. H.: The Cab -X is a very mild 246 degree (advertised) replacement for the original cams. I have a bit of trouble believing your grinder can achieve what you're telling us. By the way according to J. Mummert, you will have to shorten the valve guides to achieve that lift. I think you should go with Jim's suggestion and contact Mummert for professional advice. As I understand it, to achieve that lift from your cam, will require reducing the base circle of it & that may not be a good idea... ??
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By PF Arcand - 18 Years Ago
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H.H.: Correction- Sorry, I said Jim, I should have said "Frank"
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By Hollow Head - 18 Years Ago
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I was just calculating the possibilities of that CABX-28 cam and I have no real meaning to get that grind to that .611 inch lift. And for that turbo engine I'll keep it stock otherwise than grinding that groove to that center journal. But, it would be nice to have one cam grind to, for example, Iskys 505-t specifications and to try it with some other engine.  Anyhow, I'm still interested about Stock cams and their degrees and lifts. Opening and closing points and all that stuff. What is the correct word for the place where the cams get grind and engines bored etc? Sorry about my bad english. Should have been awake at the lessons....
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By Jim - 18 Years Ago
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Haha, should have been awake eh? Seppo, you are a funny guy!
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By Hollow Head - 18 Years Ago
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Jim, what is bad to be awake at the lessons? You just learn more and you just get more attention by being foolish yourself . ( or maybe not Snoring makes other people happy!)
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By pegleg - 18 Years Ago
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HH, Machine shop or automotive machine shop is correct. Just that most US machine shops don't have cam grinders. Most of our aftermarket cams are done by 4 or 5 specialty companies that only do cams. Well, cams and valve train parts like lifters, springs, and pushrods. Most likely they purchase most of that stuff, rebox it and sell it to us as their own. Frank
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By Hollow Head - 18 Years Ago
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My ex truck CABX 28 camshaft is now like new cam. It is done by that GT-motor machine shop in Helsinki and it is very very close to Iskys rpm-300 grind. Lift from lobe is .291" and that makes .417 lift with 1.43 rockers. Duration is 270 degrees. I was just an hour ago at my garage with LordMrFord and we did some "ultra accurate" measurements out of that cam. These are the results that are taken with .050" lifter rise:
Intake opens at 3 deg before TDC and closes at 44 deg after BDC.
Exhaust opens at 50 deg before BDC and closes at 2 deg before TDC.
So exhaust duration is 228 degrees and we got 226 degrees for intake but I quess that is measuring error with 2 degrees. So 228 to both sides.
Overlap with .050 lifter rise is then only 1 deg. I have to go back to garage and do that all again with .020 lift. But not today anymore. Last night I was assembling the block until 0.15 am!
The cost for that grind was 140 euros this time and that includes that center groove at the middle bearing surface and phosphate coating for the lobes.
Time will tell us how that works with Twin Turbo setup I hope that Jim will add some pics to this message about that cam
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