Harold's cams are NOT the "fast ramp" cams that people have had trouble with in the past. Harold's grinds are all ayssemetrical with a "relatively" aggressive opening ramp and a "relatively" gentle closing ramp. Harold has been designing cams since 1972 and seems to have it down pat. I have not had any valve float or excessive wear with his lobes. I have one circle track motor that has been to the dyno twice and has 56 nights of racing on it and the lobes are all still perfect. When I was using the Comp stuff we used to get about 18 nights out of a comparable cam before it started to eat the lobes. Also, I did run an Xtreme energy 240*/246* solid flat tappet cam (with the above mentioned "fast ramps" in my engine and it ran very, very good and I never had any issues. Then I went to a TA solid roller and about 2000 miles later ate one of the roller lifters and that's where our hero sits now. That all being said, I did not realise that TA was building the engine and I wholeheartedly agree that you should use their camshaft then. I used the TA 413 HL cam in my motor years ago and I was pleased with it.
I don't understand why Yardley seems to have so many transmission problems. Mark DeConti built him a transmission or 2, and I have never known anyone to have problems with his transmissions, but Yards has. He has also had problems with other transmissions also. I'm thinking there is some kind of problem with his linkage, or other problem with the car that eats the transmission. He needs to figure that out first.
Since Mark brought it up, and it's been decade since the last aggressive ramp cam test, I got the OK from Larry to test this Voodoo Lunati cam in his motor, and just heard back from my jobber that Lunati has one on the shelf, and it will be blue-labeled to me so I can degree it in on Friday, when I will be doing the other cams. Sitting here, I will say that the tighter lobe center cam should make more mid range pwr than the 413, but it should do it at the expense of idle quality. While it's shorter in advertised duration, that's offset by the tighter lobe centers. But I am always open to new testing, that's how you keep evolving in development with an engine that has been out of production for decades. It will also be an interesting comparison to the hyd roller. One issue for concern in our BBB motors is that nearly everyone designing lobes for a .842 lifter generally is using the BBC/SBC lifter bore angles and lobe base circles as baseline info. Adapting these lobe designs to the BBB lifter bore angle and smaller base circle can be an issue, and the more aggressive the lobe, the greater the possibility is of ending up with a lobe profile that will be rpm limited at the very least, and destructive to parts in a worst case scenario. Add in possible factory variation in the lifter bore angle from block to block, and that puts you out farther yet on the ledge. It explains why some guys say a particular cam worked great in their engine, but another guy can't get the same cam to rev past 5200 to save his life. I have found that the more engines I build,(which raises the "sample size" for testing and conclusions), the harder I lean toward lighter valve spring pressures and less aggressive flat tappet lobes. In the past, tests have shown conclusively that acceptable increases in ramp speeds in a BBB have yielded virtually no more usable power out of the engine. I am actually more interesting in the testing on this motor, than any other one (save for maybe the Supercharged 465 I just did) than I have built in some time. The advent of the hydraulic roller profiles for a BBB is the latest advance in making usable, street friendly power. But it's all in the testing.. and now we have a test which will encompass a "known" cam, a newer design, tighter lobe center cam, and then the roller. The results should be interesting.. stay tuned. JW
I will be very interested to see the results of this, Jim. I am starting on a hydraulic roller 455 myself and should have it on the dyno by the end of March or so but this camshaft test you are doing really has my interest. I will be looking for your post. Thankyou for sharing, Mark Dalquist
Watch? Wear your work clothes, and I will let you help... :TU: So far, still looks like Thursday.. call me tomorrow to confirm. JW
This will be a high profile motor. everything you want to know, we'll all know. I'm sure there will be a separate thread, probably a sticky.
Jim, are you talking about this Thursday? Unfortunately I will be in Atlanta on business. Please let me know of other fun projects in the near future that I can help you with. :beer
Well lets start the hp #'s I say 583@5700:3gears: Larry you must be busten, Listen Larry did you here that noise?That was Moon:moonu: turning his boost up!
Due to some parts delays, this dyno has been rescheduled to a week from Tomorrow, Weds the 19th. Yes, it will be it's own thread. In this thread I will be doing a step by step on cam degreeing, I have been taking pictures for 2 days now. JW
Well, it's 10:00 am CST Wednesday, Jan 19 and Jim should be making some break-in pulls by now. I've been to R+R for dyno time before and they don't screw around at all. I'm really curious to see all of the results:3gears:
Me tooray: The roller will be the last cam tested. I'm figuring it will be this evening before we know anything.
I'm thinking if Jim feels like I do after a day-long dyno thrash he won't have the energy to say anything today. I'm guessing he'll need the weekend to post results and photos but?o No:
