Rocker Ratios...variances
#11
Registered
![Default](/forums/images/icons/icon1.gif)
He does do a lot of testing and a lot of his info is valid.
Some, well,,,,,I'd have a hard time believing (we all have opnions) and some times he turns into a marketing guy.
Well worth to read his stuff, I dunno if I'd believe it all.
Anyway,
Here's some data:
500,000 / 365 days = 1 Dyno test every single day (no day off) for 1370 years.
= 2 Dyno tests every single day for 685 years
= 4 Dyno tests every single day for 343 years
= 8 dyno tests every single day for 171 years
= 12 dyno tests every single day for 114 years
= 16 dyno tests every single day for 86 years
Again, every day a week including Sundays.
Some, well,,,,,I'd have a hard time believing (we all have opnions) and some times he turns into a marketing guy.
Well worth to read his stuff, I dunno if I'd believe it all.
Anyway,
Here's some data:
500,000 / 365 days = 1 Dyno test every single day (no day off) for 1370 years.
= 2 Dyno tests every single day for 685 years
= 4 Dyno tests every single day for 343 years
= 8 dyno tests every single day for 171 years
= 12 dyno tests every single day for 114 years
= 16 dyno tests every single day for 86 years
Again, every day a week including Sundays.
#12
Registered
![Default](/forums/images/icons/icon1.gif)
He does do a lot of testing and a lot of his info is valid.
Some, well,,,,,I'd have a hard time believing (we all have opnions) and some times he turns into a marketing guy.
Well worth to read his stuff, I dunno if I'd believe it all.
Anyway,
Here's some data:
500,000 / 365 days = 1 Dyno test every single day (no day off) for 1370 years.
= 2 Dyno tests every single day for 685 years
= 4 Dyno tests every single day for 343 years
= 8 dyno tests every single day for 171 years
= 12 dyno tests every single day for 114 years
= 16 dyno tests every single day for 86 years
Again, every day a week including Sundays.
Some, well,,,,,I'd have a hard time believing (we all have opnions) and some times he turns into a marketing guy.
Well worth to read his stuff, I dunno if I'd believe it all.
Anyway,
Here's some data:
500,000 / 365 days = 1 Dyno test every single day (no day off) for 1370 years.
= 2 Dyno tests every single day for 685 years
= 4 Dyno tests every single day for 343 years
= 8 dyno tests every single day for 171 years
= 12 dyno tests every single day for 114 years
= 16 dyno tests every single day for 86 years
Again, every day a week including Sundays.
If you consider 1 pull on the dyno a test (which it should be) and you do 30-40 pulls/day it would get lower. Also, if that is your daily job/passion it is more reasonable.
![Smilie](/forums/images/smilies/smile.gif)
Last edited by Rookie; 10-05-2015 at 11:21 PM.
#13
Registered
![Default](/forums/images/icons/icon1.gif)
The first thing anyone should learn in any statistics class is... "You can make the numbers look any way you want"
If you consider 1 pull on the dyno a test (which it should be) and you do 30-40 pulls/day it would get lower. Also, if that is your daily job/passion it is more reasonable.![Smilie](/forums/images/smilies/smile.gif)
If you consider 1 pull on the dyno a test (which it should be) and you do 30-40 pulls/day it would get lower. Also, if that is your daily job/passion it is more reasonable.
![Smilie](/forums/images/smilies/smile.gif)
30 Dyno tests every single day straight for 45.6 years = the claimed number.
#15
Banned
![Default](/forums/images/icons/icon1.gif)
I posted this before as I have taken David Vizard 3 day school classes that he teaches in the USA. The guy by far is so super knowledgeable about this stuff. I run into him once a year and he told me at one time that he has tested / dynoed 18,000 cams in his lifetime. he also has stated that his daughter can pick a better cam than the cam manu's for your app. Just saying.
he loves mini coopers and is good friends with engine builder Terry Walters in Virginia who also does a lot of his engine machining.
he loves mini coopers and is good friends with engine builder Terry Walters in Virginia who also does a lot of his engine machining.
#16
Registered
![Default](/forums/images/icons/icon1.gif)
That's 1 cam everyday in a row for 49.3 years
or
2 cams everday in a row for 24.7 years.
or
2 cams everday in a row for 24.7 years.
#17
Registered
![](https://www.offshoreonly.com/forums/images/icons/platinum_member_star.gif)
Join Date: Jan 2006
Location: wisconsin
Posts: 688
Likes: 0
Received 0 Likes
on
0 Posts
![Default](/forums/images/icons/icon1.gif)
I was going to go with 1.8 intake rockers and was told by several builders that it is not a good Idea for engines running extended RPM. I shook my head thinking how bad could it be going from 1.7 to 1.8. They all said the same thing, that it would be to aggressive and bad on parts. I am hard enough on parts as it is, so I didn't even entertain the thought after that. I would love to go that route. So, Joe get them in some motors... Or anyone else that has used them with success in marine engines that are run hard for extended periods, please chime in.
#18
Registered
![Default](/forums/images/icons/icon1.gif)
Okay Lions lost. Ha ! Time to get some zzz's.
Again, having fun,
Most people (even me) like what Vizard says/does.....but remember, just because you like + trust (and what have you) a guy, doesn't mean you have to believe everything he says.
Again, having fun,
Most people (even me) like what Vizard says/does.....but remember, just because you like + trust (and what have you) a guy, doesn't mean you have to believe everything he says.
#20
Registered
Thread Starter
![Default](/forums/images/icons/icon1.gif)
I was going to go with 1.8 intake rockers and was told by several builders that it is not a good Idea for engines running extended RPM. I shook my head thinking how bad could it be going from 1.7 to 1.8. They all said the same thing, that it would be to aggressive and bad on parts. I am hard enough on parts as it is, so I didn't even entertain the thought after that. I would love to go that route. So, Joe get them in some motors... Or anyone else that has used them with success in marine engines that are run hard for extended periods, please chime in.
I think it goes deeper though. For one, whats defined as aggressive? As we know, you can have two cams that might have same .050 numbers, and one accelerate the lifter faster than the other. So, whats to say, a certain cam with 1.7 rockers, won't be harder on the valvetrain, than a milder lobed cam, with a 1.8 rocker?
I've had guys tell me the same. Don't use a 1.8 rocker. But when you ask them about the difference in lobe profile measurements other than .050, they aren't sure. Heck, some cam specialists don't even provide anything other than .050 numbers on thier custom cam cards. How is one supposed to be able to determine anything about the camshaft, with simply providing .050 duration and xxx lobe lift? I guess most don't care to know, and simply trust their cam guy to know whats best. Or the effect of big lift lobes, coupled with short duration, etc. What kind of detrimental effects are we talking? What kind of HP gains are we looking at? Is it worth the expense? I really don't know.
I know Mike Jones from Jones Camshafts discusses some of this stuff on other forums. From what I gathered talking to him myself, is that for marine offshore hydraulic stuff, he simply isn't a fan of short durations with lobe lifts over .370ish for valvetrain longevity/stability, talking standard cam core bbc stuff. Seems like his thinking, coincides with what Crane, Comp, and some others offer for marine endurance hydraulic bbc profiles.
Last edited by MILD THUNDER; 10-06-2015 at 12:21 AM.