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#141
11-21-2011, 02:06 PM
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11 or 12.6 casting
my understanding from a mag. article is that they are 2 different castings. Heres a quote from the article.
The Victor Pontiac casting was designed to accept a traditional '65-'79 intake manifold, such as a Performer RPM or Victor. "In order to accomplish this, we raised the intake and exhaust ports by 5/8-inch and lengthened the intake port 5/8-inch on the 12.6-degree casting," says Garcia. "The 11-degree casting is raised and lengthened approximately 1.25 inches. The added intake-port length gives a tunnel-ram effect, which greatly influences airflow and performance. Either casting accepts conventional round-port headers." Read more: http://www.highperformancepontiac.co...#ixzz1eMeWixfb |
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#142
11-21-2011, 03:15 PM
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If someone would send me a 12.6 degree head I would be glad to look it over and provide some real measurements on comparison with the 11 degree here. I will return it quickly on my dime no problem.
Calvin, What did you hit on your head? Spring pocket?? Area between spring pocket and rocker boss? Water? Don, Did you hit anything when you were porting? At this point I have only rubbed up against the head bolt..no air or water. |
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#143
11-21-2011, 05:42 PM
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Has anyone checked the valve angles in their heads? Just wonderin if they are 11° or 12.6°. Did you get what you ordered?
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#144
11-21-2011, 06:06 PM
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The extream difference of the location of the intake port should be a dead give away???
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#145
11-21-2011, 08:29 PM
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Quote:
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#146
11-22-2011, 11:22 AM
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Jim, I did not hit anything on my 428 cfm port except the pushrod hole, and only about a third of it is showing. So it will require an offset rocker although not much, I'd say maybe .150 offset. So with the port I have right now, a .180 offset lifter would allow the push rod to pretty much be straight up and down. I have not poured my port yet to see how big it is, but an educated guess would be around 300 cc's with the extra flange area. If it did not have the extra material on the flange I would guess around 270 cc's. I did not go crazy big anywhere for this port version on purpose trying not to blow through the roof. I could see from looking at the port that the spring pocket was very close and would pose a problem. I don't see any problem though with getting somewhere around 450 cfm by just widening my port a little more and raising the port entry just a little. I think that I will still be in the safe zone and not blow through anywhere. I just need to get a little time to play some more with it. Never enough hours in a day LOL!!
I did check my valve angle and it is 12.5 + or _ a degree. Don Johnston DCI MOTORSPORTS INC. 330-628-3354 cell 330-850-5050 shop Designer of the DCI Tiger Heads and the NEW DCI Ram Air V heads!!!! |
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#147
11-22-2011, 02:01 PM
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Don -- are you saying that you see 450cfm potential out of the 12.6 head ???? Has anyone varified that they have an 11 degree ?? and any current numbers ??
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#148
11-23-2011, 12:44 AM
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Quote:
Calvin already at 440 and not done. 12.6 casting. |
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#149
11-23-2011, 01:34 AM
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A few more measurements
These are definitely 11 degree valve angle as measured from the deck surface. Pic 1 shows 4.4955" from the deck to the top of the casting at the intake flange adjacent to the intake port. Is this what you were looking for Curt? Pic 2 shows 3.202" from the machined spring pocket to the valve seat insert machined shoulder. As I compare the pics from the March 2011 issue of HPP magazine these have spring pockets machined much shallower. Pic 3 shows some progress... Pic 4 shows how Victor sits on these heads. Top of Victor runners align near perfect with the top of head cast. Bolt holes in head align very nicely with Victor openings |
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#150
11-23-2011, 10:47 AM
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When I measure the casting I have the same way Jim measures his in pic 1, I get 4.475.In my opinion that's close enough to call the same. All the guides are in mine so I cannot get a measurement the same as Jim's for the spring pocket, but if I measure from the unmachined part of the casting down to the spring seat. I get a depth or around .252 to .256 deep.
So unless Edelbrock machines the deck surface differently, it appears that the castings are the same. It looks to me like what they done is use the same casting just made two different intake port cores and raised the 11 degree port up a little higher to begin with. Nothing that good head porter couldn't do on his own when porting. Jim, I don't know if you can get an accurate measurement off the valve cover rail on the intake side, but if you can I get about 4.700 to the deck. Curt, I think I could probably get 500 cfm out of one of these heads, but it will not happen without ALLOT of welding and ALLOT of work. And we all know that means ALLOT of money. Don Johnston DCI MOTORSPORTS INC. 330-628-3354 cell 330-850-5050 shop Designer of the DCI Tiger Heads ad the NEW DCI Ram Air V Heads !!!! |
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#151
11-23-2011, 01:18 PM
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Those of you that have a head what do you think of the exhaust port? Seen it mentioned that to make more power the exhaust side is going to need more work.
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#152
11-23-2011, 01:25 PM
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Jim -- the pics are great - -ty - Don -- I hear what you are saying-- IMO -- If the head can be done in a 450 to 465 cfm configuation - and duplicated in a CNC setup --I think we wil have a winner no welding - no epoxy - ext. Jims port is giving me a little stiffy - jk
Good luck all |
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#153
11-23-2011, 01:45 PM
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Slowbird, remember the valves are pushed off the X axis opposite directions and the centerline is measured off the X axis, giving more between the valves.
I think these should be done focusing beyond what we have now. I see 470+ potential and 8000+ RPM 535's. And I wouldn't even consider the Victor even at 440CFM levels. |
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#154
11-23-2011, 01:45 PM
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#155
11-23-2011, 01:50 PM
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#156
11-23-2011, 02:02 PM
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450-465 cfm with no welding of epoxy.
OK, what is the difference between that and that Tiger, where a 450-465cfm CNC port job is already available? Is is cost, quality , producibility , what. Because it sure looks like the performance will be the same. If it will not be able to beat 1100 HP NA with a single 4, whats the point. |
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#157
11-23-2011, 02:05 PM
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IMHO Victor intake is "small" for a 430cfm head and will take lots of work to get it to a better size. We have ported the Victor to +4.0 square inches beginning runner area and it could stand a bit more area still to work with this particular engine combination and performance goals
Don showed in post #191 that the 12.6 degree is 4.475." |
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#158
11-23-2011, 02:18 PM
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#159
11-23-2011, 02:20 PM
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#160
11-23-2011, 02:26 PM
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