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By Hollow Head - 14 Years Ago
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I'm just comparing different alternatives for the next camshaft into our next engine and as there is lots of cams, it would be nice to know what cam is most powerful. Ted could propably do that easily, if he just gets all the cams for a test session? Ok, for us, it might not be so helpful as we deal with boost and that makes things a little different. But for others with normally inhaling engines it would be great source of information. Right now I'm leaning to Isky RPM-300 with 112 degree lobe separation angle. Also Comp Cams 37-600-5 Thumpr seems interesting with 268/287 degree Adv. duration. Only negative with that is tight 107 degree LSA. Schneider has also couple of interesting cams and so does Howard Cams too. And then there is an option with custom grinds  ... What would you think about 268 / 301 degree cam to clear the boosted gasses out of the cylinder...
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By Riz - 14 Years Ago
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I would be a big fan of this. I started another thread wondering which one. Long time ago I was finishing a build with a 351 and tried to get the most radical cam. Spent forever getting it in and set up only to find that I actually lost hp and torque. The set up just really did not work with the heads and intake. Learned a great lesson at 19 that not all top shelf stuff works well together.
I might commit to some good bourbon to whomever steps up.
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By PF Arcand - 14 Years Ago
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Hey guys! testing different Cams in a Y-Blk ain't easy. Ted has provided much information that just isn't available anywhere else.. and largely at his expense, particularly with respect to his time. Lets not push our good luck! Try John Mummert re Cam info, he seems to have a comprehensive grasp of what works or doesn't with our favorite engine.
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By paul2748 - 14 Years Ago
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I too would like to see something like this. My ideal would be a 292/312, G heads mostly stock, stock compression ratios, 4 bbl carb, affordable ignition. 350 rear. A good street engine.
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By aussiebill - 14 Years Ago
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PF Arcand (12/18/2011)
Hey guys! testing different Cams in a Y-Blk ain't easy. Ted has provided much information that just isn't available anywhere else.. and largely at his expense, particularly with respect to his time. Lets not push our good luck! Try John Mummert re Cam info, he seems to have a comprehensive grasp of what works or doesn't with our favorite engine.Paul, i gotta agree with you, Teds imput and R & D is beyond all expectations, cams and results differ with head changes etc and think there are enough theory,s on what works best where. Merry Xmas to all.
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By Glen Henderson - 14 Years Ago
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I agree, this would be a very expensive test, money and time. We used the Isky 505T in my engine and although it has very poor idle , the thing makes good power. Now if someone could convince the cam grinders to provide there products to Ted for testing, he could give them some good data.
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By Hoosier Hurricane - 14 Years Ago
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I agree that such a test program would be expensive, and I also think that even if Ted was given test cams for free, he should be paid by someone at his regular shop hourly rate to test them. Changing cams and lifters in a Y block is a rather time consuming process.
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By Y block Billy - 14 Years Ago
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Didn't someone have a virtual site in a previous post they could go to to see different HP's and torque numbers for different grind cams. May not be spot on but would give a ballpark figure.
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By LordMrFord - 14 Years Ago
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Engine Analyzer is good program to test camshafts and other stuff virtually, but needs a lot of input data and the most Y-Block Camshaft sellers don't have a lot of information on their sites.
...and other thing is port dimensions, lenghts and flows, huh.
More input info, more accurate result.
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By Ted - 14 Years Ago
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Ditto on the previous comments. Camshaft testing is time consuming to say the least while also being expensive. Besides just the camshaft swap, then there are a multitude of other variables that must be considered for each swap. Some of these include moving the installed cam position around, intake manifolds, header sizing, lash settings, carburetion, jetting, and ignition timing to just name a few. I’m currently dyno testing a 390 Ford and that test has evolved to the point of trying another camshaft. That means that many of the other variables that were tried on the first camshaft must now be rerun with the revised camshaft. But the only way to know for sure is to do the test as a computer program designed to calculate HP/TQ for a SBC is not going to be accurate enough in this case to define exactly what the results are going to be.
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By Grizzly - 14 Years Ago
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Guys, What a pandoras box?  I've always seen camshaft choice as a very personal thing as it is one of the big deciders in the engines personality. Seppo from what I know about camshafts for turboed engines (and I know nothing) they do not like overlap. Turbo engines require higher exhaust pressure than intake pressure to work. overlap can allow the pressure differential to even out. The best camshaft for a turboed Y is a special. See a cam grinder. Cheers Warren
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By Ted - 14 Years Ago
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Seppo. Grizzly is spot on with his cam thoughts as a custom cam for a boosted application would be a better fit than an off the shelf cam for a normally aspirated Y application. Blower and turbo cams have similar characteristics in that the lobe centerline is increased to reduce the amount of overlap and the exhaust valve typically opens earlier than normal to give a jump start to the scavenging process. With that in mind, here are the specs for the cam in Randy Gummelt’s dragster. Adv duration = 288° Int / 294° Exh Dur at 050 = 254° Int / 260° Exh Lobe centerline = 114° Lobe lift = 0.350” Int / 0.346” Exh This is a custom ground Isky cam and works well with fifteen pounds of boost and 7.5:1 static compression ratio. A single dyno pull was made with this cam with a four barrel carb prior to installing the supercharger and even in this format the engine performed surprisingly well and especially considering how low the compression ratio is. Here’s the link to the YBM article giving some more details on Randy’s engine including some dyno numbers. 8 Second Y Engine
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By Hollow Head - 14 Years Ago
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Jep, Ted. I knew that overlap thing and as I said, Isky RPM-300 has also that 114 degree LSA. It has more lift and the same advertised duration 270 /270 as our recent cam. And I read somewhere that folks are using more and more cams with more exhaust duration nowadays, so that is why that Comp Cams Thumpr interests me. But, how much is too much? Well, time will tell where we end up... again... .
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By Jerome - 14 Years Ago
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Just a thought, There is a Clevelands Forever Fourm member, Dan Jones, who is using engine sumulation software from Dynomation to spec cam shafts for some of his friends. He also ran a 351C dyno mule engine testing various intakes and head combinations. Dynomation is not free and it requires a lot of precise measurmentd data on intake and exhaust as input, but Dan seems to be satified with the results. Just a thought at another way someone with access to all the right parts could put together something of value to others. Jerome
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