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Discussion Starter · #1 ·
Some of you may know that Mike sent me a head off his 302 to look at as long as I flow benched it. Finally after 6 months of waiting I have the numbers. Since it is Mikes head I would prefer he see's the numbers before he or I post them for all to see. I will state this though. Fords exhaust port does not suck as much as every one thinks. It just needs work. What does suck is the intake port. The peak numbers are not that high, but the low lift numbers are very impressive. Well on par with most aftermarket aluminum street heads. Who says you can't go fast with stock parts. Will Post numbers as soon as Mike see's them.
 

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I got these numbers from John, and was expecting a bit more from the intake... maybe it was the old valve job or how the heads were set up on the bench.


I know very little about how the flowbench was set up, only that the guy seemed pressed for time. I don't know if the intake opening was radiused with clay, or if the guy used a pipe on the exhaust. All I do know is that there were several years worth of abuse on the valve job... it was not fresh by any stretch of the imagination.
The valves were 1.94" intake, 1.60 exhaust.

Intake -- Exhaust

.1 063 -- 050.9
.2 119 -- 101.3
.3 168 -- 132.8
.4 201 -- 157.1
.5 210 -- 175
.6 218 -- 176.6

My intake volume was 155cc. (stock is 126cc) Comparing to the best of the aftermarket competition, here are AFR's published numbers for their fully CNC ported non emission 165's...

intake -- exhaust

.1 ----- ----
.2 123 -- 118
.3 186 -- 153
.4 225 -- 178
.5 243 -- 185
.6 250 -- 191

As long as there is no significant shrouding, or the short turn isn't too messed up, larger vavles will flow more at lower lifts. They provide a much larger window... especially when they are only opened a small amount. However, opening the bowls up large enough for a 1.94" intake valve is QUITE risky. The metal get VERY thin when the WHOLE bowl is opened up to around that size. I'd say 351W valves (1.84" / 1.56&quot
would be nice in a 289 head.

I might try widening the intake port floor as much as is practical before the short turn. (I didn't know this trick until after those heads were already finished and on the car)

The exhausts did surprisingly well. I guess my design there worked out pretty well.


If John wants to publish some pictures, that would be great... John, just clean the head up a tad first.


Good Luck!
_________________
Mike Burch, 66 mustang real street
302 4-speed 289 heads, 10.63 @ 129.3
http://www.geocities.com/carbedstangs/cmml_mburch.html
http://www.fortunecity.com/silverstone/healey/367

<font size=-1>[ This Message was edited by: n2omike on 6/5/02 8:40pm ]</font>
 

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Here's a good site that has all sorts of small block flow data grabbed from various magazine articles. I can't stand for the validity of 'magazine' numbers, (or even my own)
but, it doesn't look like I did too bad for a 'good ole boy' who's never even seen a flowbench in real life.


http://www.jason.fletcher.net/tech/flowdata/castiron.htm

How did the Fordmuscle heads do? How bout' the rest of you guys? Any numbers to share? Looks like my numbers came out quite a bit better than the 289 heads in the 400hp Joe Sherman 400hp 302 buildup... Here's a link to the Sherman article:

http://www.jason.fletcher.net/tech/sherman/sherman.htm

Comparing to the aftermarket, and seeing what Joe Sherman was able to do with his flow numbers, I guess it's a good thing we don't race flowbenches....


Fletch has a pretty good website. He runs the carbedmustang email list.

http://www.jason.fletcher.net

Good Luck!
_________________
Mike Burch, 66 mustang real street
302 4-speed 289 heads, 10.63 @ 129.3
http://www.geocities.com/carbedstangs/cmml_mburch.html
http://www.fortunecity.com/silverstone/healey/367

<font size=-1>[ This Message was edited by: n2omike on 6/5/02 9:28pm ]</font>
 

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Discussion Starter · #5 ·
Mike I know he mentioned claying up the intake when I talked to him, and it looks like he did from some residue on the head. It is my impression that most places don't use the pipe on the exhaust, but I will call and find out for sure. I kinda forgot to ask these questions while I was there, since I wasn't expecting them to be done when I showed up.
Comparing the numbers to the AFR doesn't really show how good the head is. Using the numbers for the edelbrock performer or gt-40x, from the Fordmuscle archives, you will see that your actual have more area under the curve.

For quick reference
edelbrock gt-40x
Intake Exhaust intake exhaust
.1 56 44 56 49
.2 114 91 105 105
.3 166 132 154 141
.4 200 160 192 158
.5 214 171 210 162
.6 215 176 225 169

Sure some guy's are saying that either of these heads has more potential, but I think this illustrates that a guy on a limited budget doing his own backyard port work with a little knowledge can make power with stock heads. I have also been trying to widen the port floor as Mike suggests on my own "practice" head. I am finding this difficult to do, as that is one of the thin spots Mike talks about, once you blend the bowl in. If attempting this be VERY careful. After seeing these numbers, I think I am going to take my head down to the shop and have them flow that one also, to see how much moving the intake port into the pushrod area helped flow. I acommplished this by installing a valve guide in the pushrod hole. I was amazed at how far over you can push the entire port, straightening it out for a better shot at the valve. I guess I got kinda long, I better shut up now.


<font size=-1>[ This Message was edited by: jdsgallops on 6/5/02 10:18pm ]</font>
 
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