Cam and valvetrain longevity....??? low duration high lift...
#1331
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I have not been home until tonight to even touch the rest, going to clean parts later and post pics...
I did oil change 2 hours ago, cut filters open and looked great, I don't see evidence of metal anywhere, valve tips, rollers on lifters lol good, rollers on rockers looked good at a quick glance, I will clean them and report back. I think I caught it right before the point of actual tearing up metal began...
Once on a stand I will eventually pull some caps and see what's up and hope for best... If I have issues I'm gonna part the whole mess out and buy a set of used running hp500 parts boat and go boating lol
I did oil change 2 hours ago, cut filters open and looked great, I don't see evidence of metal anywhere, valve tips, rollers on lifters lol good, rollers on rockers looked good at a quick glance, I will clean them and report back. I think I caught it right before the point of actual tearing up metal began...
Once on a stand I will eventually pull some caps and see what's up and hope for best... If I have issues I'm gonna part the whole mess out and buy a set of used running hp500 parts boat and go boating lol
Last edited by Full Force; 10-06-2016 at 04:56 PM.
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#1332
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I like how back when bob asked our friend joe, to provide him with an invoice, with what i and icdedppl paid for our daytona boxes, and that he would match that price and beat it. I gave that info to our buddy, in which he forwarded it to bob. The next day, we get a call from our local machine shop that we bought them from, explaining how he got yelled at by the owner of daytona for selling them at that price. Bob did that, because he was pizzed that we purchased 6 ign setups, and didnt go thru him. As well i how here on oso, i told a few who were looking at those boxes, to call the local shop, and they would give an oso discount. How dare i step on bobs toes being he was an advertiser here, and a daytona dealer. Then he got really angry, when he specd out 3 bar map sensors for my buddys setup, that i was going to be programming , when i told my buddy he needed to call bob, and exchange for 2 bar units. So , he calls bob, and bob in his usual stern tone of voice, tells my buddy, "you need a 3bar map if you want to have a 3d timing curve " . My buddy joe, not knowing better calls me back, and tells me that. Getting aggravated, i simply said, well maybe you neef to have bob build you a map then. Needless to say, the 2 bar came , and all went well.
Whats even better about that, is i have helped out at least 7 of his customers who purchased those boxes from him, and needed help setting them up, building and uploading maps, and so on. Which i do not mind doing to help a fellow boater out. The question is, why arent they having bob do that for him, h3es the one selling them, making a profit on them, and yet, it seems as if theres no support .
I could go on about how he was selling those boxes on someone elses account, and that whole story, but Im sure people are getting bored of hearing stories.
Whats even better about that, is i have helped out at least 7 of his customers who purchased those boxes from him, and needed help setting them up, building and uploading maps, and so on. Which i do not mind doing to help a fellow boater out. The question is, why arent they having bob do that for him, h3es the one selling them, making a profit on them, and yet, it seems as if theres no support .
I could go on about how he was selling those boxes on someone elses account, and that whole story, but Im sure people are getting bored of hearing stories.
Last edited by endeavour32; 10-06-2016 at 05:12 PM.
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#1335
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#1337
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I cant help but notice when visiting cam motions site, the lack of things pertaining to big block stuff, besides 8.1 truck cams, let alone bbc endurance stuff. Looks like they specialize in LS engine stuff.
Does anyone know if they spintron test their lobes with bbc components?
Does anyone know if they spintron test their lobes with bbc components?
Doubt the spintron, not many companies do. Not many years ago, no cam companies had spintrons. Squeezing my gray matter together I think it was Mondello who started designing/building spintrons.
They are heavy into their computer program and cnc'ing most, if not all their cams. So, if all these cams are having instability and/or heat treat problems, I think their methods really come into question also.
Reading there sight as far as custom cams is very strange. You can pick a duration at .050", lift, and lsa and they'll grind you a cam. I thinkthat is relying to heavy on a computer program for me.
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#1339
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ok so from beginning to date of this thread there has been a lot discussed. Some off the subject in question but mostly involving input with combos, cam specs, lobe flaws with premature failure etc. To me it's evident something has changed drastically over the last couple years with rmbuilder but perhaps much longer. Difficult to say as we don't have all input going back several years (decade or more). Especially when we upgrade our builds, sell engines and lose track of the long jevity of the said engine and valvetrain. Just saying we're constantly changing builds, going bigger, adding SC's, procharger's, tunnel rams and so on which in most cases involves cam and valvetrain in most cases. So in a nutshell who's to say how long who's cam last and who's doesn't.
Other thread MT started may shed shed some more light on that. List is growing without a doubt. Good bad indifferent.
What I have come to the conclusion for the most part here is without a doubt duration goes up with cubic inch to maintain peak hp at a given rpm. (Pretty common knowledge for most part). Also obviously short duration higher lift cams are causing valvetrain stability all over. You'd think after all the years of techknowledgey and R&D there would just be a simple ratio rule of thumb (lobe/duration). Yet most likely there is that's why you don't see cams similar to the ones in question being sold by most all cam companies.
I will have to admit I am shocked to learn how much duration is needed to achieve peak hp let's say 6,000-6,200 on a 540-548. What I am understanding for the most part is on a 540-548 build with 315-325 cc heads is you should be looking at a cam 250/260-700/690 plus or minus. Heads being 100% professionally set up is crutial. If in doubt send them out... Every single moving part pertaining to valvetrain including lifter bore alignment, size, etc all equally important.
I recall MT posting some CI's vs duration differences but would be kinda of neat to really narrow it down with most common builds. Runner cc can change up duration so formula would never be a 100% accurate but at least get many people in the ball park. Head runner 305-335 (probably average based on CI below)
Just keep 6,000 rpm as a guideline for all engines.
496-509
540-548
555-565
572-598
Some variables may apply such as same CI with different stroke but just looking for general duration. Might be best for another thread however I think would be helpful for many individuals as well as builders. Example when you look up a cam in cam book it's not real specific with 396-454 or some 396-502. I have seen 540 plus occasionally however I think what we could do here would be helpful. Lift rates easier to determine based heads and flow at various lifts.
As many cam threads that come up I think this would be helpful for many.
Other thread MT started may shed shed some more light on that. List is growing without a doubt. Good bad indifferent.
What I have come to the conclusion for the most part here is without a doubt duration goes up with cubic inch to maintain peak hp at a given rpm. (Pretty common knowledge for most part). Also obviously short duration higher lift cams are causing valvetrain stability all over. You'd think after all the years of techknowledgey and R&D there would just be a simple ratio rule of thumb (lobe/duration). Yet most likely there is that's why you don't see cams similar to the ones in question being sold by most all cam companies.
I will have to admit I am shocked to learn how much duration is needed to achieve peak hp let's say 6,000-6,200 on a 540-548. What I am understanding for the most part is on a 540-548 build with 315-325 cc heads is you should be looking at a cam 250/260-700/690 plus or minus. Heads being 100% professionally set up is crutial. If in doubt send them out... Every single moving part pertaining to valvetrain including lifter bore alignment, size, etc all equally important.
I recall MT posting some CI's vs duration differences but would be kinda of neat to really narrow it down with most common builds. Runner cc can change up duration so formula would never be a 100% accurate but at least get many people in the ball park. Head runner 305-335 (probably average based on CI below)
Just keep 6,000 rpm as a guideline for all engines.
496-509
540-548
555-565
572-598
Some variables may apply such as same CI with different stroke but just looking for general duration. Might be best for another thread however I think would be helpful for many individuals as well as builders. Example when you look up a cam in cam book it's not real specific with 396-454 or some 396-502. I have seen 540 plus occasionally however I think what we could do here would be helpful. Lift rates easier to determine based heads and flow at various lifts.
As many cam threads that come up I think this would be helpful for many.
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#1340
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Most look ok, there's a couple that might look like they bounced around a little, my spring pressures were not equal so that could be it, in a nutshell..I was spec'd a disaster waiting to happen....[ATTACH=CONFIG]560179[/ATTACH][ATTACH=CONFIG]560180[/ATTACH][ATTACH=CONFIG]560181[/ATTACH][ATTACH=CONFIG]560182[/ATTACH][ATTACH=CONFIG]560182[/ATTACH][ATTACH=CONFIG]560183[/ATTACH][ATTACH=CONFIG]560184[/ATTACH][ATTACH=CONFIG]560182[/ATTACH]
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