Cam specs? whats duration at.050??
#1
Gold Member
![](https://www.offshoreonly.com/forums/images/icons/gold_member_star.gif)
Thread Starter
Join Date: Oct 2005
Location: Olmsted Falls,Ohio Marblehead,Oh
Posts: 11,635
Likes: 0
Received 204 Likes
on
132 Posts
![Default](/forums/images/icons/icon1.gif)
My custom ground cam only has the advertised duration engraved, I do not have the cam card....
trying to see what duration it is....
I do know...
ground 114LCA
Says advertised duration 302/310
lift is .578
its erson.... cannot find what duration is @.050
how do I find that out??
trying to see what duration it is....
I do know...
ground 114LCA
Says advertised duration 302/310
lift is .578
its erson.... cannot find what duration is @.050
how do I find that out??
#4
Gold Member
![](https://www.offshoreonly.com/forums/images/icons/gold_member_star.gif)
Thread Starter
Join Date: Oct 2005
Location: Olmsted Falls,Ohio Marblehead,Oh
Posts: 11,635
Likes: 0
Received 204 Likes
on
132 Posts
![Default](/forums/images/icons/icon1.gif)
Yes that's the only thing I don't know... My buddy had a engine builder that I would have shot hence the reason I build my own stuff but this was a deal so I grabbed the boat....
I know he built them very conservative using small cams for the CI... I plan to change things in a couple years or if I hurt one and rebuild... These can make 675-700 hp easily...
Right now they are 598hp@5200 659tq@4200
Hp is 597-598 from 5100-5400 then drops off...
Tq peaks 4200 but still hold 607@5200 so 5200 is about what I wanna prop at also
I know he built them very conservative using small cams for the CI... I plan to change things in a couple years or if I hurt one and rebuild... These can make 675-700 hp easily...
Right now they are 598hp@5200 659tq@4200
Hp is 597-598 from 5100-5400 then drops off...
Tq peaks 4200 but still hold 607@5200 so 5200 is about what I wanna prop at also
#6
Registered
![Default](/forums/images/icons/icon1.gif)
Put a degree wheel, dial indicator and pointer on it.
#8
MarineKinetics
![](https://www.offshoreonly.com/forums/images/icons/platinum_member_star.gif)
![Default](/forums/images/icons/icon1.gif)
Full Force,
The cam is a derivative of the shelf cam:
E120207
RH-302-2
234º/242º @ .050"
.340"/.340" Lobe
Ground on a 114º Lobe sep
Attached is the cam card for theat cam on a 112º sep, measured with a 1.72 rocker ratio.
Bob
The cam is a derivative of the shelf cam:
E120207
RH-302-2
234º/242º @ .050"
.340"/.340" Lobe
Ground on a 114º Lobe sep
Attached is the cam card for theat cam on a 112º sep, measured with a 1.72 rocker ratio.
Bob
#9
Gold Member
![](https://www.offshoreonly.com/forums/images/icons/gold_member_star.gif)
Thread Starter
Join Date: Oct 2005
Location: Olmsted Falls,Ohio Marblehead,Oh
Posts: 11,635
Likes: 0
Received 204 Likes
on
132 Posts
![Default](/forums/images/icons/icon1.gif)
So it's close to that? What's the 310 for on the back? Any idea? This cam seems small for 547ci aluminum head engines 320cc runners I think I have that info at home
#10
MarineKinetics
![](https://www.offshoreonly.com/forums/images/icons/platinum_member_star.gif)
![Default](/forums/images/icons/icon1.gif)
Yours is identical to the catalog cam sheet posted, with the exception of yours is ground on a 114º lobe separation angle, and the catalog cam has been ground on a 112º LSA. Duration, lift etc. is all the same.
the 302º/310º designates the seat, or measured duration. I posted the catalog cam to give you a look at the lobe architecture.
"Hp is 597-598 from 5100-5400 then drops off..."
That is typical of that duration for that displacement, power will plateau, dropping off due to pumping losses.
Bob
the 302º/310º designates the seat, or measured duration. I posted the catalog cam to give you a look at the lobe architecture.
"Hp is 597-598 from 5100-5400 then drops off..."
That is typical of that duration for that displacement, power will plateau, dropping off due to pumping losses.
Bob