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As I've posted before I'm building a 292 for bracket racing. I'm using EFI with a mega squirt controller and a turbo.I've built a log type intake manifold with an injector for each cylinder located close to the port in typical fashion. One of the forum members sent me a message saying with these types of ports it doesn't work to well. What can I do? Can I help it with the controller,bigger injectors? I've got to much time and money in my intake to change directions. Anybody got any suggestions? Thanks.
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Inliner Member 1716 65 Chevelle Wagon and 41 Hudson Pickup Information and parts www.12bolt.com
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That old thread is EYE opening! Just when I think I've gained a little bit of knowledge I realize that I know less than a little!  Harry - good luck
If at first you don't succeed,
then read the directions and try again.
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So how far up into the intake should the dividers reach? Just up to the injectors? Thanks for the help guys.
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Ideally, it should seperate the port into (2)equally sized and proportioned sections, and extend all the way to the rear of the port wall.
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Thanks for the help but could you explain what the problem is with the ports that they don't like EFI? Or is it the combo of EFI and a turbo? It seems the added volume of the second port would allow more flow with a turbo? Is overall power down or just at low speeds? Thanks again.
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Because the ports are siamesed, you are going to always have one that will try to rob fuel from the other because of the cam overlap and having a shared intake port, even if you put(2)nozzles in each port.
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Two things, first a new EFI manifold, but they only show one for the Holden; http://cgi.ebay.com/ebaymotors/ws/eBayIS...RK%3AMEWAX%3AITSecond just to clarify the EFI problem is with injectors on each port, not TBI? Larry
Last edited by LGriffin_#4385; 06/12/10 10:02 AM.
Ignorance can be fixed Stupidity is forever
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Larry,
You are correct. EFI with 1 injector per port on a siamesed port will not run good. Dividing the port makes a world of difference.
Tom
Inliner Member 1716 65 Chevelle Wagon and 41 Hudson Pickup Information and parts www.12bolt.com
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But... what's that dog-leg turn into the end ports?
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That is one part of the reason I like it better.
If it were a 6 port intake manifold,I would not like that design,but since it is for a siamesed port, I think it will work better.
MBHD
12 port SDS EFI 
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So... the angle favors one end port of each pair (#1 & 6, or 2 & 5) in the intake sequence (where there is an imbalance), and the center runner has none because those cylinders (#3 & 4) have an equal and balanced 360° interval?
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Sorry, hard for me to explain.
MBHD
12 port SDS EFI
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Harry, Search the forums for divided port information, the problem is worse with carbs. The small port hurts air flow but the turbo makes up the difference. The reason for this promlem is in the valve timming of each port not just the overlap of the cam. It has been all covered in other posts.
Harry
Turbo-6
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