Pro comp cylinder head question

[Hass828]

here's a link to some more stuff on the heads:
http://www.superflowheads.com/bbchev.html
same heads, just sold under another name
Tom I believe that the link you provided is for a different head as the one in the link is made in austrailia, I think thats the same company that made the pro top line and pro action heads and their pretty bad ass heads, I've got a set of 360 protoplines. These procomps are a chinese copy the best I can tell.

[gn7]

Sorry guys, Jetaholic is right. If you're running a big roller with .800 lift, you're not going to run a standard length valve, no matter what the geometry is. This is why there's a choice of valve lengths in teh standard legth (whatever that is) + .100, +.200, or whatever. The added length is to accomodate taller installed height springs which may be required depending on the cam. The geometry issues are definately a factor, and one of the reasons you step up to a performance head. Canfields (and most other performance alum heads) are designed using a .100 long valve. This way when you need a spring with 2" installed height, which is likely if you're stepping up to aluminum heads, you won't have those geometry issues as mentioned.
Originally, on the drawing board, the length of the valve was worked out with everything else in consideration to get the right geometry, but it alone was not the deciding factor. In this case, valve length is dictated by installed height of the spring. Period. If you have to run a long valve and it's causing geometry problems, it's time for better heads. Adjusting installed height with offset retainers isn't really the way to go, but it works in a pinch. Another way is to cut the spring pads, but you have to be careful about getting into water on some hedads. Taking off .050 isn't usually a problem, and a better solution than offset retainers. Offset retainers often cause retainer to rocker interfearance. The valve tip needs to extend far enough above the retainer to allow for full rocker articulation. It might be OK with a 1.4"-1.5" dia. spring, but get into the bigger springs and you're usually going to have problems.
Just my .02
yeah and then they but in the wrong pushrod anyway, over arc/under arc and none of the above means jack chit anyways

[Jetaholic]

yeah and then they but in the wrong pushrod anyway, over arc/under arc and none of the above means jack chit anyways
Ain't that the truth

[IMPATIENT 1]

Tom I believe that the link you provided is for a different head as the one in the link is made in austrailia, I think thats the same company that made the pro top line and pro action heads and their pretty bad ass heads, I've got a set of 360 protoplines. These procomps are a chinese copy the best I can tell.
they're the same heads hass, i called em the procomp heads are a PROTOPLINE knock off, not dart, not edelbrock, just protopline(rhs).

[IMPATIENT 1]

http://***boat.com/forums/attachment...1&d=1197999319
http://***boat.com/forums/attachment...1&d=1197999498
no difference externally

[fc-pilot]

Sorry guys, Jetaholic is right. If you're running a big roller with .800 lift, you're not going to run a standard length valve, no matter what the geometry is. This is why there's a choice of valve lengths in teh standard legth (whatever that is) + .100, +.200, or whatever. The added length is to accomodate taller installed height springs which may be required depending on the cam. The geometry issues are definately a factor, and one of the reasons you step up to a performance head. Canfields (and most other performance alum heads) are designed using a .100 long valve. This way when you need a spring with 2" installed height, which is likely if you're stepping up to aluminum heads, you won't have those geometry issues as mentioned.
Originally, on the drawing board, the length of the valve was worked out with everything else in consideration to get the right geometry, but it alone was not the deciding factor. In this case, valve length is dictated by installed height of the spring. Period. If you have to run a long valve and it's causing geometry problems, it's time for better heads. Adjusting installed height with offset retainers isn't really the way to go, but it works in a pinch. Another way is to cut the spring pads, but you have to be careful about getting into water on some hedads. Taking off .050 isn't usually a problem, and a better solution than offset retainers. Offset retainers often cause retainer to rocker interfearance. The valve tip needs to extend far enough above the retainer to allow for full rocker articulation. It might be OK with a 1.4"-1.5" dia. spring, but get into the bigger springs and you're usually going to have problems.
Just my .02
You brought up a great point. On the aftermarket heads I dealt with I was using lift that would make full use of their potential (.700 to .800 lift at the valve) therefore needing the full length valve the head manufacturer suggested. I have never tried setting up a head like this for a low lift flat tappet setup like this. After reading your comments you brought up some great points to the idea of altering the stem length.
Paul

[Hass828]

they're the same heads hass, i called em the procomp heads are a PROTOPLINE knock off, not dart, not edelbrock, just protopline(rhs).
so are the procomps made in china or austrailia? what about the superflows? are superflows and procomps the same head? I understand that RHS now owns the protopline castings.

[IMPATIENT 1]

so are the procomps made in china or austrailia? what about the superflows? are superflows and procomps the same head? I understand that RHS now owns the protopline castings.
there's no more protopline, rhs acquired them, then rhs sold(i think to comp cams). the procomps, protopline, superflow, rhs are all the same design castings.the super flows and procomps are knocks offs of the oe protopline 320cc head(now rhs). tricky bastards aren't they i even went as far to pull the 320cc protopline head flow numbers and guess what, the superflow 320cc flow numbers list as the same,lol.
i do know the protopline heads were made in australia , couldn't tell where they're made now. the superflows and procomps are chinese copies. only difference between the protopline 320cc head and the procomp 320cc head is that procomp made the intake port thoat alittle smaller(like a 7/8ths rect)instead of the full rect port like protoplines. you can stick your finger in the intake ports of the procomp and see how they made them to be ported back to the protopline rect port design. procomp was trying to avoid a lawsuit is my guess. either way, after a gasket port match of the procomp heads, they're "supposed" to have the exact same intake ports as the protoplines. i'd like to see a set of protoplines and procomps side by side to compare.

[fast boat]

http://www.boatstoreonline.com/procomp.html
ENOUGH SAID!

[IMPATIENT 1]

http://www.boatstoreonline.com/procomp.html
ENOUGH SAID!
when did small blocks come into this thread? if you've got a link on dyno'n with the bbc heads, that'd be helpful