This is a cut and paste from an email last year that I sent to Barrry at SDAC, which later appeared in one of the SDAC newsletters:
*** Stock G-head *** (intake ports only)
#1 #2 #3 #4
.100 46.2 45.2 44.2 46.6
.200 93.2 94.2 92.7 93.7
.300 128.1 126 128.8 125.7
.400 150.5 147.9 151 148.4
.500 161.5 160.6 160.6 162.2
***Stock G-head w/stock 1-pc Intake***
#1 #2 #3 #4
.100 44.1 45.4 44.3 45.2
.200 85.2 87.3 84.6 87.3
.300 108.9 109.9 108.5 112
.400 121.5 122.5 119.7 123.9
***Stock G-head w/ stock 2-pc Intake***
#1 #2 #3 #4
.100 49.4 50 45.2 45.4
.200 89 88.2 86.5 86.7
.300 113.4 111.3 111.3 109.2
.400 126 123.9 120.4 119.7
.500 133.7 130.9 125.3 124.6
***Stock G-head w/mildly modded 1-pc Intake***
#1 #2 #3 #4
.100 49.7 49.7 43 45.1
.200 88 89.5 83.9 86.5
.300 110.6 112.7 107.8 112.7
.400 122.5 123.9 119.7 125.3
.500 130.2 128.8 125.3 132.3
***Stock G-head w/mildly modded 2-pc Intake***
#1 #2 #3 #4
.100 49.4 50.4 44 45.2
.200 89 89 88.2 85.8
.300 114.8 113.4 112 110.6
.400 128.8 126.7 123.2 119.7
.500 136.5 134.4 128.8 125.3
***Stock G-head w/stock 2-pc lower half only***
#1 #2 #3 #4
.100 46.1 50.5 45.4 46.6
.200 88.3 90.8 90.3 90.5
.300 116.9 117.6 117.6 119.7
.400 132.4 131.7 129.6 130.3
.500 144.4 142.6 137.3 139.1
***Stock G-head w/mildly ported 2-pc lower half only***
#1 #2 #3 #4
.100 46.5 51.2 45.3 46.4
.200 89.8 92.3 90.5 91
.300 119.7 120.4 119.7 119
.400 135.2 135.2 131.7 131
.500 147.9 146.1 140 140.8
***********Stock 1pc Intake Flow Losses*************
#1 #2 #3 #4
.100 2.1 +0.2 +0.1 1.4
.200 8 6.9 8.1 6.4
.300 19.2 16.1 20.3 13.7
.400 29 25.4 31.3 24.5
.500 32.3 31.8 35.3 32
****Stock 2pc Intake Flow Losses****
#1 #2 #3 #4
.100 +3.2 +4.8 +1.0 1.2
.200 4.2 6.0 6.2 7
.300 14.7 14.7 17.5 16.5
.400 24.5 24 30.6 28.7
.500 27.8 29.7 35.3 37.6
****Mildly modded 1-pc intake Flow Losses****
#1 #2 #3 #4
.100 +3.5 +4.5 1.2 1.5
.200 5.2 4.7 8.8 7.2
.300 17.5 13.3 21 13
.400 28 24 31.3 23.1
.500 31.3 31.8 35.3 29.9
****Mildly modded 2-pc intake Flow Losses****
#1 #2 #3 #4
.100 +3.2 +5.2 0.2 1.4
.200 4.2 5.2 4.5 7.9
.300 13.3 12.6 16.8 15.1
.400 21.7 21.2 27.8 28.7
.500 25 26.2 31.8 36.9
That's it!!!! Probably should find the flow losses for the 2-pc lower halves as well as you can see that a large majority of the intake's flow losses appears to occur in the runners of these intakes...not the plenum and it's 90 degree elbow at the TB. Also, the "+" numbers in the flow loss charts represent flow GAINS when the intake is bolted on the head. It seems that very low lift flow is increased when the intake is bolted on.
For the cylinder head tests... I calibrated the bench before use, and I used the temperature correction factor I told you about earlier to keep things on a more level playing field. (as well as running leakage tests) I did this on every port and every lift # on every single test. On the head alone, I made my own inlet guide. I tested it against the ever popular clay inlet guide(s) of the old school variety and it appeard right on. I tested it w/out either and there was an actual cfm loss w/out it. I forget the exact #, but it was around a 7-10 cfm loss.
For the intake testing, I blocked off every vacuum port, injector boss, etc... in the head and left all the valves closed to block off all the cylinders being tested excpet for the ones... actually being tested. I made sure the valves would seal good, so for added insurance, I used a bit of light grease on the 45 degree seats. For the entrance to the plenum of each intake, I bolted on a special large radiused inlet guide that bolted in place of the stock TB.
The intakes in question: The mildly moddified 1 and 2 piece intakes are pretty much just that. I welded the backsides of the runners where the indentations are for the bolts that clamp the manifold to the head. Internally, I removed the "humps" and then re-drilled and counterbored the are for use of socket head cap screws in place of the normal bolts. The 1-pc actuall had the TB area opened up for a 52mm TB, where the 2-pc upper was untouched. You can see from the flow tests that on both intakes, there's only a couple cfm advantage of doing this mod. Oh well... a couple cfm here...a couple there....
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UPDATE: a few months ago, I ported the lower half of one of my 2-piece intakes fully. Put darn close to 35-40 hours into it doing it through breaks and my lunch hour (why it took longer than normal). I bolted the stock intake bottom half to a ported test head that flowed a little over 180cfm on the intake at .500" The stocker lost 29 cfm on the ported head vs low 20s on a stock head. I swapped out the stock bottom for my new ported bottom and my flow losses went from 29 cfm, down to only 13cfm. In the next few weeks, I will be doing the top half and plenum area fully with alot of new ideas implemented (ie: tricks) and from what I have been told/learned, I should be able to drop the flow losses even further. I got rid of my flow losses in the exhaust manifold (to the tune of 11-17 cfm gains... posted info in the exhaust section just now) and getting the intake side down would be great.
Originally Posted by 22mopar
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) where people compile.... just that, and is seperate from how to's and model descriptions, etc.
Frank Katzenberger
