Did some home porting on a set of GT-40p's

[Visceral]

Got my flow data back today from Hutchins Machine Shop (a damn nice place and a really intelligent guy).

Ive attached the flow info... Im really excited. I'm looking at mild cams to put with them.

I tried to make a crude measurement of port volume, adn came to the rough conclusion that these new intake ports are only about 10% larger than the E7TEs. I *barely* removed any material. I should have some mad velocity.

Heres a poor paste... see the attachment for the better view.

Stock E7TE
Int Ex
0.1 59 42
0.2 114 78
0.3 144 105
0.4 156 115
0.45
0.5 156 116
0.55
0.6

As Cast GT-40p
Int Ex
61 50
125 92
169 130
195 142
199 146
193 147
197 149
196 149

Ported
Int Ex
66 54
133 107
174 148
203 163
208 168
201 171
203 174
205 176


Ported and seats radius cut
Int Ex I/E
66 59 0.89
129 112 0.87
183 155 0.85
211 172 0.82
207 175 0.85
204 177 0.87
206 177 0.86
206 176 0.85

 

[Rootus]

Not bad numbers! It'll be interesting to see how they perform. When are you installing them? Are these formerly Gregg's?

Dave

 

[Visceral]

Not bad numbers! It'll be interesting to see how they perform. When are you installing them? Are these formerly Gregg's?

Dave

Yeah I was just looking at some stock AFR 165 and Edel 6037 numbers and I match them all the way to .450 lift, where i stall out and the AFRs keep going up. But I have smaller valves . So I am looking forward to installing them.... this winter Yeah, I just dont have time to get involved in a full on head/cam swap right now. I'll email you when its planned though. I'll be making sure Gregg is on hand.

Are they the heads formerly known as "Gregg's castings"? Until I finish paying him for them, they still ARE "Gregg's castings" . I keep trying to bait him into some kind of $300 wager I know I can win

 

[Rootus]

Yeah I was just looking at some stock AFR 165 and Edel 6037 numbers and I match them all the way to .450 lift, where i stall out and the AFRs keep going up.

Crack smoker . The AFR's have you by 7% at 0.400, and it gets ugly to the tune of almost 20% at 0.500 .

With all the prepwork you've done, though, you'll probably be withing spitting distance of my numbers when you get those P's on. I'll be curious to see how that curve looks, we'll see how the velocity on the P's compares to the velocity on the 165's (since AFR specifically designed the 165's for velocity, that should be a good yardstick to measure by).

Dave

 

[Visceral]

well if I have almost the same flow #s, (I went to Ed Curtis's place and they sure looked close to me...), my ports are roughly 150cc. SO hows THAT for velocity?

from FordMuscle:
http://www.fordmuscle.com/archives/2003/02/afr/index2.shtml
(atually a really cool article and set of tables)

Intake
lift (in.) AFR my gt-40p's
.100 60 66
.200 125 129
.300 188 183
.400 226 211
.500 238 207
.600 248 (my cam isnt going *near* 600)

Exhaust
lift (in.) AFR My GT-40p's
.100 52 59
.200 100 112
.300 142 155
.400 168 172
.500 181 177
.600 189 (again, no 600 for me)
Damn... my low lift numbers look *great* compared to a $1400 set of AFRs! And since Im looking at a cam with .510 peak lift, Im pretty psyched!
You know how important PEAK flow #s are, right?
My $300 set of heads looks better each time I look at those numbers
Now I'll see if I can beat a $450 custom cam with a $175 off-the shelf design that Ive carefully chosen. You'll notice with me .84 I/E, I can run a cheap single pattern cam...
AND I got all this great flow with 1.84/1.46" valves

 

[Rootus]

well if I have almost the same flow #s, (I went to Ed Curtis's place and they sure looked close to me...), my ports are roughly 150cc. SO hows THAT for velocity?

Strap it down, and let's find out! . (BTW, I just used the numbers from AFR -- 225/178 @ 0.4, 243/185 @ 0.5)

Dave

 

[Visceral]

Strap it down, and let's find out! . (BTW, I just used the numbers from AFR -- 225/178 @ 0.4, 243/185 @ 0.5)

Dave

wait.. I have to install this stuff? daaaaaaammmnnn... Hold up for a minute...