[turbo2256b]

at home in my friends garage

 

[bindirdundat]

what machine do you have the cyl head on,ya gotta give us a little more info on this..

 

[turbo2256b]

Its an old Bridgeport converted to CNC using probing and cutting softwere developed by us.

 

[bindirdundat]

Its an old Bridgeport converted to CNC using probing and cutting softwere developed by us.

Are you developing a cnc program to port factory iron heads ??

 

[turbo2256b]

Have developed programs for many heads SBFs were one of the first. Some Asian stuff most American stuff. Even developed a SBC head for Brodex and porting programs.
3 sets of E7 heads one set ended up on my caer for a while.

 

[bindirdundat]

Have developed programs for many heads SBFs were one of the first. Some Asian stuff most American stuff. Even developed a SBC head for Brodex and porting programs.
3 sets of E7 heads one set ended up on my caer for a while.

What are some before and after flow #'s on a set of cleveland heads and what would the cost be too get a set of cyl heads ported out,very interested in this..

 

[turbo2256b]

351C closed chamber 4V heads 2.19 int 1.71

lift ----intake/exh before-----------after
.100------64.3/66.7---------------70/64
.200-----115.8/103.3-------------131/107
.300-----163.5/133.8-------------198/145
.400-----210.0/154.4-------------248/169
.500-----246.0/169.0-------------300/192
.600-----273.6/178.4-------------322/200
.700-----279.0/166.0-------------330/200

 

[bindirdundat]

351C closed chamber 4V heads 2.19 int 1.71

lift ----intake/exh before-----------after
.100------64.3/66.7---------------70/64
.200-----115.8/103.3-------------131/107
.300-----163.5/133.8-------------198/145
.400-----210.0/154.4-------------248/169
.500-----246.0/169.0-------------300/192
.600-----273.6/178.4-------------322/200
.700-----279.0/166.0-------------330/200

Not bad those are some pretty good gains,is there more to be found on the exh side,do you have any completed pics.

 

[turbo2256b]

Only thought on the exh side is possibly a larger exh valve. Dosent always work that way.
Most C cams are set up for a lot of extra lift and duration on the exh side to help compensate.

 

[bindirdundat]

Only thought on the exh side is possibly a larger exh valve. Dosent always work that way.
Most C cams are set up for a lot of extra lift and duration on the exh side to help compensate.

Not a whole lot of room for too much of a bigger valve,but I have seen hand ported at around 225 230 at .700 lift on the exh with some very carefull short side radius work,some even just cut out the whole valve guide area in the pocket and smooth it out fully.

 

[bindirdundat]

Only thought on the exh side is possibly a larger exh valve. Dosent always work that way.
Most C cams are set up for a lot of extra lift and duration on the exh side to help compensate.

Did you manage to get any finished pics of the port job completed.

 

[turbo2256b]

Sorry no pics of heads just the intake ported

 

[bindirdundat]

Sorry no pics of heads just the intake ported

The head numbers you posted are those the final numbers you got,

 

[turbo2256b]

Yes they were the finial figures. Also Pic of the intake is the intake manifold.
Will mention heads intake port flow is about as much as possible at max flow as possible while still increasing low lift numbers. Most wont list low lift numbers or if they do it is usally lower than as cast figures. Total air flow is what is important to us. We always look at "total air flow", add all the lift points air flow togeather .1 + .2 + .3 + etc. Also air speed has to be concidered vs engine displacement vs rpm range/engines intended usage.

Stan Weiss' - Cylinder Head Flow Data at 28 Inches of Water -- DFW / FLW Flow Files for use with Engine Simulation Software
Look here for compairisons

 

[bindirdundat]

Yes they were the finial figures. Also Pic of the intake is the intake manifold.
Will mention heads intake port flow is about as much as possible at max flow as possible while still increasing low lift numbers. Most wont list low lift numbers or if they do it is usally lower than as cast figures. Total air flow is what is important to us. We always look at "total air flow", add all the lift points air flow togeather .1 + .2 + .3 + etc. Also air speed has to be concidered vs engine displacement vs rpm range/engines intended usage.

Stan Weiss' - Cylinder Head Flow Data at 28 Inches of Water -- DFW / FLW Flow Files for use with Engine Simulation Software
Look here for compairisons

That makes sense,do you offer this service and how much to port a set of Cleveland heads ??