Good Cam Choice?
Below is the substantial flow testing done by Steve Dulcich, published in MM Feb 1999. Dulcich worked with D. Vizard, which could be where the idea to use a 30* seat came from.
Note:
- Column 7. Hard to read but the 30*, seat fully ported, flowed more at every lift from 0.025" to the max lift of 0.650". 346 head.
- Column 8. 30* seat, template ported, flowed more up to 400 lift. Serious flow loss started after 500 lift. 452 head
- 30* seats were tested with 2.14" valves because you cannot convert a 2.08" seat from 45 to 30.
Comments by SD on the 30* seat:
- 'Why throw away 25% better flow?
- The already excellent midrange flow reached astoundingly fat numbers, with strong double digit gains all the way to .500 inch lift. The top end flow showed moderate improvement.
In this form, this IS A KILLER STREET HEAD for STREET or RACE applications, with moderate cam lifts.
On the early 915/906 heads, the 30* seat provided substantial gains up to 0.250'lift
Below is the substantial flow testing done by Steve Dulcich, published in MM Feb 1999. Dulcich worked with D. Vizard, which could be where the idea to use a 30* seat came from.
Note:
- Column 7. Hard to read but the 30*, seat fully ported, flowed more at every lift from 0.025" to the max lift of 0.650". 346 head.
- Column 8. 30* seat, template ported, flowed more up to 400 lift. Serious flow loss started after 500 lift. 452 head
- 30* seats were tested with 2.14" valves because you cannot convert a 2.08" seat from 45 to 30.
Comments by SD on the 30* seat:
- 'Why throw away 25% better flow?
- The already excellent midrange flow reached astoundingly fat numbers, with strong double digit gains all the way to .500 inch lift. The top end flow showed moderate improvement.
In this form, this IS A KILLER STREET HEAD for STREET or RACE applications, with moderate cam lifts.
On the early 915/906 heads, the 30* seat provided substantial gains up to 0.250'lift
