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semi siamesed runners

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Old May 16, 2002 | 08:36 AM
  #1  
ausrs's Avatar
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From: New South Wales Australia
semi siamesed runners

is there any benefit to doing this modification ?? if so what would i expect ?
Attached Thumbnails semi siamesed runners-3.jpg  
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Old May 16, 2002 | 10:45 AM
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From: Orygun
a WHOOOOOLE lotta work to only still be stuck with an LTR setup

Thats as much effort as modifying an LT1 intake which offers better gains.
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Old May 16, 2002 | 10:53 AM
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From: Stuarts Draft, VA
Car: 88 GTA
Engine: modified L98
Transmission: 700r4
Axle/Gears: 3.27 9-bolt
Siamesing the runners effectively shortens the runner length, and should move the powerband up in the rpms a little bit. It should net you a few horsepower.
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Old May 16, 2002 | 12:10 PM
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From: Somewhere over the rainbow
The runners in the picture were a waste of time in my opinion.
The problem with the stock runners is that the tube diameter is
too small. They can not flow enough air. Those runners are still
exiting to the base through the stock diameter tubes.

If they would have siamesed the bottom of the runners instead,
they would have had the same effect that madmax accomplished
with siamesing the base. Each base port would be able to draw
from two runners instead of just one.
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Old May 16, 2002 | 01:37 PM
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From: Texas
Yeah, stock size runners would be a waste but those are AS&M LTR semi siemesed runners so they are big tubes and siemesed. Still, they will end up costing you 500.00 for a set. Can't say that they are worth the cost with so many other new alternatives out there now.
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Old May 16, 2002 | 04:34 PM
  #6  
Scott 88 GTA's Avatar
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From: Stuarts Draft, VA
Car: 88 GTA
Engine: modified L98
Transmission: 700r4
Axle/Gears: 3.27 9-bolt
Originally posted by Swapmaster
The runners in the picture were a waste of time in my opinion.
The problem with the stock runners is that the tube diameter is
too small. They can not flow enough air. Those runners are still
exiting to the base through the stock diameter tubes.
It depends on what you want to accomplish. If you just want more power within your current powerband, then yes, go with larger tube runners.

If, however, you want to move your powerband up a few hundred rpm siamesing the runners will do that for you. In reality, if you siamese them for the entire length it would move your powerband up the most.

Siamesing larger tubed runners as Gruvin84SS suggested would provide the most benefit.

Granted, for the price of larger runners you could get the entire Holley Stealth Ram, so to most people it's a moot point anyway.
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Old May 17, 2002 | 01:34 PM
  #7  
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From: Winnipeg,MB
Car: 1991 Camaro Z28
Engine: 350 L98
Transmission: 700R4
You can siamese the slp runners.
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Old May 17, 2002 | 02:36 PM
  #8  
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From: Somewhere over the rainbow
Stock siamese.
Attached Thumbnails semi siamesed runners-junner1.jpg  
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Old May 17, 2002 | 02:37 PM
  #9  
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From: Somewhere over the rainbow
Stock siamese
Attached Thumbnails semi siamesed runners-runner2.jpg  
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Old May 17, 2002 | 02:39 PM
  #10  
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From: Somewhere over the rainbow
Stock siamese, I have $15 invested so far.
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Old May 17, 2002 | 04:34 PM
  #11  
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From: Finland, Europe
cool job Swap! :hail: when you're going to throw those on and tell us the results? just wondering, are you going to siamese also the flanges to look like sunglasses?



-P
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Old May 17, 2002 | 05:09 PM
  #12  
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From: Edmond, OK, USA
Car: 87 IROC
Engine: 305 TPI going to LT1
Transmission: 5spd
i am also very very interested in how that goes. looks great. i know you wanted a stock appearance but would it have been much harder to to the outside of the runners like you did the inside?
thanks
Andrew
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Old May 18, 2002 | 09:54 PM
  #13  
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From: Somewhere over the rainbow
Go over here https://www.thirdgen.org/techbb2/sho...8&goto=newpost where I have a thread running
documenting the whole proccess. Yes the flanges will get the
sunglass cut and the base will be ported and the entrances
matched to the runners.
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