Muscle Mustang & Fast Fords
 

I got the new issue the other day, and was curious if anyone saw part I of the new series on flow testing of the small block heads? Generally,I take the data printed in the magazines with a "grain of salt", but I think these numbers seem reasonable. I know flow isn't everything but here are some points of interest:

- The old GT-40 heads flowed better than the GT-40P throughout the entire range(both intake & exhaust)

- The Holley (20 degree) heads peaked at .400 lift intake.

- The TFS heads out flowed the AFR (165) up to .500 intake. The AFRs put up some impressive exhaust flow numbers (over 180 cfm from .500 - .700 valve lift).

Overall, I thought it was a pretty informative article and am looking forward to next months issue. I would of liked to see the Edlebrock Performers tested, they quoted the manufactures peak numbers (226 cfm int./175 cfm exh.@.600) but didn't test them. The Brodix ST 5.0 heads looked pretty good, but the TFS heads might be in the near future.

T.J.

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1989 lx notch
89,000 miles
bolt-ons,stock heads/cam
60'- 2.07, 8.90@78, 13.93@99

[This message has been edited by TJR (edited 04-23-2001).]

[This message has been edited by TJR (edited 04-23-2001).]

[This message has been edited by TJR (edited 04-24-2001).]

From what I've seen on tests both in magazines and on the internet, the TFTW and the AFR 165's run really close. Canfields can do well for street heads but the availability is REALLY SPOTTY. If you order these, be sure you can cancel payment easily. This is only what I've heard, not personal experience. TFTW may need clean up as they're kinda rough from what I've heard. The AFR's are CNC machined and well done I've heard. Check a lot of other sources, as I'm still in the research stage myself. I think I'll get the TFTW and get them ported for myself.

Rev

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'66 Coupe, 306, 300 HP, C-4, 13.97 e.t., 100.3 mph
1/4 mi.

I've been trying to decide on what heads to buy ever since I bought my car. There are so many options out there, it's amazing. I've done my share of looking around through the internet, magazines, books, other mustang owners, etc... It seems like people have had really good results with almost all of them. There are some pretty impressive ETs/MPH coming from some of the cars on the Corral running the AFRs. I'd like to see those heads get some mileage on them though, to see if they have any problems (guides/springs). I like the Brodix ST 5.0 heads but I rather have stud mount rockers. Also, I don't know if I could justify $1400 for the AFRs. I still got a few months before I'll be able to buy heads anyway. Until then I'll keep sorting out the pros/cons for each brand and hopefully make up my mind.

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1989 lx notch
89,000 miles
bolt-ons,stock heads/cam
60'- 2.07, 8.90@78, 13.93@99

What were the flow numbers for the old GT-40's? I have a set of them and I was wondering how they flowed compared to other heads. I have a chance to buy a set of Edlebrock Performer RPM (1.90 in, 1.60 ex) off of my cousin for $700, and they have never been bolted to anything (they just sat in his room).

Thanks,

Jason

Here are the flow numbers on the old GT-40s along with a few of the other heads. These numbers are estimates since they used graphs in the magazine. (vl=valve lift, in=intake, ex=exhaust).

GT-40
vl- .100 .200 .300 .400 .500 .600
in- 60 115 160 180 190 190
ex- 50 90 120 125 126 126

GT-40P
vl- .100 .200 .300 .400 .500 .600
in- 55 110 152 180 185 190
ex- 40 75 100 118 122 126

GT-40X
vl- .100 .200 .300 .400 .500 .600 .700
in- 58 110 160 200 220 225 222
ex- 50 90 128 138 148 149 148

Brodix ST 5.0
vl- .100 .200 .300 .400 .500 .600 .700
in- 62 125 175 215 235 240 240
ex- 50 90 125 150 162 170 175

Holley (20 degree)
vl- .100 .200 .300 .400 .500 .600 .700
in- 60 125 178 222 215 216 220
ex- 40 100 130 147 150 151 149

TFS
vl- .100 .200 .300 .400 .500 .600 .700
in- 60 135 198 230 241 240 228
ex- 42 90 125 147 160 165 172

AFR 165
vl- .100 .200 .300 .400 .500 .600 .700
in- 55 119 175 215 235 247 244
ex- 50 110 150 175 183 185 187

This should give everyone an idea on the numbers they got from the flow bench.(Sorry if the numbers don't line up perfectly)

T.J.

------------------
1989 lx notch
89,000 miles
bolt-ons,stock heads/cam
60'- 2.07, 8.90@78, 13.93@99

[This message has been edited by TJR (edited 04-25-2001).]