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The Ford E7TE head appears to be very responsive to some basic porting. While the gains
are becoming smaller and harder to come by, non the less, they still keep coming.
Below is a chart that documents each step of my amature port work on the E7. The flow numbers,
cfms, are calculated to 28" of water. Each porting step is denoted with a number, that
corresponds to a short descripition and photo, or drawing, below.
Flow testing was done with a
micro flow bench from
Flow Performance. A 4.5 hp shop vac supplied the air and all CFM values have been calculated to 28" water column by the Flow Performance FP1 electronic flow bench processor.
Project E7 Part II, Intake Port flow results
| Lift |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
13 |
14 |
15 |
| .1" |
58 |
62 |
61 |
62 |
64 |
64 |
63 |
64 |
64 |
64 |
63 |
63 |
63 |
66 |
67 |
| .2" |
112 |
113 |
114 |
113 |
114 |
114 |
113 |
114 |
115 |
118 |
118 |
118 |
117 |
118 |
119 |
| .3" |
141 |
145 |
148 |
152 |
152 |
152 |
151 |
151 |
152 |
152 |
152 |
152 |
153 |
152 |
153 |
| .4" |
153 |
156 |
162 |
164 |
165 |
166 |
166 |
168 |
166 |
169 |
168 |
169 |
169 |
169 |
169 |
| .5" |
159 |
167 |
169 |
172 |
177 |
175 |
174 |
175 |
177 |
178 |
178 |
179 |
179 |
181 |
180 |
| .6" |
164 |
170 |
172 |
178 |
178 |
180 |
182 |
182 |
183 |
184 |
186 |
187 |
186 |
187 |
188 |
CFMs calculated to 28" of water
You will notice that some steps actually hurt flow. Some more than others. And
while some may have hurt flow at some lifts, gains were seen at other lifts.
[No. 1]
Column No. 1, in the chart above, are the flow numbers I measured for the single, stock, untouched test intake port with a stock valve.
[No. 2]
The valve guide is trimmed. More attention was given
to the outboard side. The backside of the guide was
contoured to let air move around the back to the inboard
side of the bowl.
[No. 3]
The intake valve is relieved, or unshrouded. The two
pointers at the left show this work. This example
increased the chamber volume by about .2cc's.
Click here for more on
unshrouding valves.
How much is a cc? The large blob of water is one cc
(cubic centimeter). The smaller blob of water is .2 cc.
[No. 4]
The short side radius (just above the pointer) is smoothed
and blended from the port floor to the throat bore. Careful
attention is made not to change the radius any more than
needed to make a smooth transition.
[No. 5]
The outboard corner of the short side radius, indicated by the
pointer, is cut back and blended effectively making the short
side radius wider.
[No. 6] The bowl outboard wall is cut back a bit
[No. 7]
The transition from bowl casting to throat cut on the
inboard side of the bowl is smoothed a bit, forming a
generous radius instead of an obtuse edge.
[No. 8] The pushrod bulge on the outside radius wall of the
intake port is smoothed down flush with the wall. This reduced the
pushrod wall thickness by about .030". My calculations showed the walls
to be about .125" thick, if the heads were cast perfectly.
[No. 9]
The pushrod bulge on the inside radius wall is smoothed.
Again, about .030" was removed.
[No. 10] A 30 degree cut is made .035" wide,
on the stock intake valve
[No. 11] A 60 degree cut is made .035" wide,
on the stock intake valve.
Readme.txt Step 11 is not recommended.
This step will be removed from Part II at a future date.
[No. 12]
The inside radius wall has the radius increased. About .035"
of material is removed.
[No. 13] The outside radius wall is contoured to try to
complement the radius on the inside radius wall. Again, about
.035" of material is removed.
The finished port opening is now about 1.010" wide.
If my measurements and calculations are correct,
and the head was cast perfectly centered and square,
the pushrod walls should still be .070" thick.
[No. 14]
With a Flepro 1250 intake gasket located via
the head gasket, it looks like Ford positioned
the ports for the most advantagous angle to the
valve (stock port on the right). I removed the
very small amount at the roof, (port at left).
[No. 15]
I removed a little more material from the
outboard side of the pocket.
Porting results so far
| Lift |
Stock |
Ported |
Results |
| .1" |
58 |
67 |
+9 |
| .2" |
112 |
119 |
+7 |
| .3" |
141 |
153 |
+12 |
| .4" |
153 |
169 |
+16 |
| .5" |
159 |
180 |
+21 |
| .6" |
164 |
188 |
+24 |
| AUC |
70.5 |
78.2 |
|
At this point, the intake port volume is 130.4 cc's. That is about 4 cc's more
than when I started.
The AUC is the Area Under the Curve, which is kind of an average rate of flow for all lifts.
I will be doing more work on the E7 intake port. It has become a real challenge for me.
I will probably work some more on the valve guide, short turn radius and the port
entrance. Also, I will be doing a lot of work on the valve. Nothing has yet
been done to the valve seat. So, what do you think? 200cfm with a stock valve
possible? Part III will tell the story.
E7TE Part 3