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Sheet metal Tunnel ram
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tsanchez View Drop Down
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Posts: 1967 		Post Options Post Options   Quote tsanchez Quote  Post ReplyReply Direct Link To This Post Topic: Sheet metal Tunnel ram
    Posted: Jul/28/2010 at 11:19am
Welcome Paul, thanks for the insight!! Have you built any AMC stuff?


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Paul Swartz View Drop Down
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Posts: 4 		Post Options Post Options   Quote Paul Swartz Quote  Post ReplyReply Direct Link To This Post Posted: Jul/28/2010 at 11:04am
Originally posted by Ken_Parkman

...Unfortunately you will have a rough time making that square to the port so you will have an angle between the head and the intake runners.

Another option would be the 4th harmonic with a total length of 10.9", or 5.4" intake manifold runner. That will package easier, but be down in power from the longer runner.
 
This is a common problem on OEM style (as opposed to raised-port race heads).  The trajectory of the runner is VERY important.  Tilting the runner up is not a good idea.  I just delivered a short "4th harmonic" tunnel ram (my first), but I can't say for sure if that's the right way to go either.  I should have dyno numbers by next week.
 
I've had good luck with plenum sizes from 70% to 120% on V-8's.  If you keep it small, you can add height with spacers under the top to find what it likes.
 
Sorry to interrupt, but I saw some web traffic coming from this thread.  I used to own an all-original 4 speed Rebel Machine. and I wrenched on a '69 AMX drag car in high school (my first wheelie in a car!)...always had a soft spot for AMC's.
www.swartzracingmanifolds.com
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Aljav View Drop Down
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Posts: 557 		Post Options Post Options   Quote Aljav Quote  Post ReplyReply Direct Link To This Post Posted: Jul/25/2010 at 11:32pm
THANKS!!

You made me finalize what I was thinking. Pretty much what I was thinking was the same I appreciate the input.. Now time to finish my ideas and get our fabricator to get going on the intake!!Thumbs Up

Thanks
Allan


Edited by Aljav - Jul/25/2010 at 11:33pm
69 AMX 10.24 129 mph 71 JAV/AMX and 69 Javelin, .. NAMDRA member #1106
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tsanchez View Drop Down
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Posts: 1967 		Post Options Post Options   Quote tsanchez Quote  Post ReplyReply Direct Link To This Post Posted: Jul/25/2010 at 11:04am
Without runners. The plenum doesn't start until runners end. And that is max volume, you can make it smaller up to the point that it is individual runner. Smaller the plenum the larger the carb you need to run, we used to run a cleveland on the street with a tunnel ram without the top and bolted 1150s to it individual runner and it ran great.

Edited by tsanchez - Jul/25/2010 at 11:13am


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Aljav View Drop Down
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Posts: 557 		Post Options Post Options   Quote Aljav Quote  Post ReplyReply Direct Link To This Post Posted: Jul/25/2010 at 1:28am
Plenum volume..TR- same as engine CI.. without Runner or with runner volume?

Allan
69 AMX 10.24 129 mph 71 JAV/AMX and 69 Javelin, .. NAMDRA member #1106
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tsanchez View Drop Down
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Posts: 1967 		Post Options Post Options   Quote tsanchez Quote  Post ReplyReply Direct Link To This Post Posted: Jul/24/2010 at 1:54pm
Remember that that would be for a dry intake in a fi application. TR would be different look at the link I provided for the big ford at 500 inches and the one I posted for a small block. Those are from pipe max.
 
Small chevy:
3rd Harmonic= 12.830 (ProStock or Comp SheetMetal Intake)
Plenum Runner Minimum Recommended Entry Area = 2.632 to 2.961 Sq.Inch
Plenum Runner Average Recommended Entry Area = 3.026 Sq.Inch
Plenum Runner Maximum Recommended Entry Area = 3.091 to 3.657 Sq.Inch

Minimum Plenum Volume CID= 58.8 [typically for Single-Plane Intakes]
Maximum Plenum Volume CID= 355.1 [typically for Tunnel Ram Intakes]

500 ford:
3rd Harmonic= 13.787 (ProStock or Comp SheetMetal Intake)
Plenum Runner Minimum Recommended Entry Area = 3.056 to 3.438 Sq.Inch
Plenum Runner Average Recommended Entry Area = 3.513 Sq.Inch
Plenum Runner Maximum Recommended Entry Area = 3.589 to 4.247 Sq.Inch

Minimum Plenum Volume CID= 68 [typically for Single-Plane Intakes]
Maximum Plenum Volume CID= 502 [typically for Tunnel Ram Intakes]


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Posts: 557 		Post Options Post Options   Quote Aljav Quote  Post ReplyReply Direct Link To This Post Posted: Jul/24/2010 at 12:37pm
Thanks for your info,,I have been on the Swartz site so many times I can't tell you...LOL And a many  other sites.

Your total number appears to be big by the number presented below.. they call for half of total CI
http://www.grapeaperacing.com/tech/inductionsystems.pdf
But I have hear as much as the total CI. But I was also under the impression when they talked plenum I thought they were talking about just the plenum not the runners included.

I keep running into 4 cylinder guy who mention even large plenums.

Yours numbers give me at least some clue where I need to be..I think


Thanks,  Allan




Edited by Aljav - Jul/24/2010 at 12:38pm
69 AMX 10.24 129 mph 71 JAV/AMX and 69 Javelin, .. NAMDRA member #1106
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tsanchez View Drop Down
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Posts: 1967 		Post Options Post Options   Quote tsanchez Quote  Post ReplyReply Direct Link To This Post Posted: Jul/24/2010 at 10:40am
http://www.swartzracingmanifolds.com/tech/index.htm


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tsanchez View Drop Down
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Posts: 1967 		Post Options Post Options   Quote tsanchez Quote  Post ReplyReply Direct Link To This Post Posted: Jul/24/2010 at 9:46am
My old UR18 has individual plenums of about 125ci each joined by a channel of about 25ci. This makes the whole plenum about 275-300.


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Aljav View Drop Down
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Posts: 557 		Post Options Post Options   Quote Aljav Quote  Post ReplyReply Direct Link To This Post Posted: Jul/24/2010 at 9:33am
Any one have a idea on Plenum sizes?  I have not found a consistent idea about plenum volume.

I have my ideas on the runners dimension but not a good idea on plenum volume yet.

Thanks Allan
69 AMX 10.24 129 mph 71 JAV/AMX and 69 Javelin, .. NAMDRA member #1106
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