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Q's on cam choice

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Old Jan 8, 2006 | 09:57 PM
  #31  
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Gears don't play much of an issue with drivability with a looser converter. The gears will help it leave harder typically speaking though. The gears will also help a bigger cam get in the sweet spot better more importantly.

Higher gears will usually make a converter stall at a lower than rated rpm, for example, my Hughes 3000 flashes at about 2800 with the 4.10's.
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Old Jan 9, 2006 | 08:31 AM
  #32  
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I would go with the 224. Cams in that range are matched well to the stock TB and intake. Plus the majority of aggressive cams dont like back pressure and it seems the bigger you go the more they dont like backpressure, so unless you plan on doing full exhaust and some head work I would stay away from the big cams. The smaller one will outperform em with a close to stock setup.
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Old Jan 9, 2006 | 10:19 PM
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I've noticed that my big am likes back pressure. It runs better and idles better with the cut outs closed than it does open.
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Old Jan 10, 2006 | 08:50 AM
  #34  
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i already have full exhaust, so i am covered on that end, so, i would need to go with a bigger gear than a 3:42? would a 3:73 be ok?
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Old Jan 10, 2006 | 08:51 AM
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what do you mean "looser" converter? higher stall?
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Old Jan 10, 2006 | 12:49 PM
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Yes ... the converter stalls, the higher the stall rating of the converter, the 'looser' it is.
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Old Jan 10, 2006 | 02:36 PM
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Originally Posted by Flyer
I've noticed that my big cam likes back pressure. It runs better and idles better with the cut outs closed than it does open.
This has a lot to do with the size of your exhaust lobe compared to the intake (233/239).
Swapping them to a (239/233) would make the motor respond best to open cut-outs.
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Old Jan 10, 2006 | 10:24 PM
  #38  
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How so ... Seems like it would be just the opposite.
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Old Jan 11, 2006 | 01:34 PM
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Flyer,

Does your setup have a better throttle response at lower RPM with the exhaust system closed up?

Here's why I made my statement...
A given intake lobe needs X amount of exhaust to operate in a certain amount of RPM.

Just too simplify... purely an example.
220/220 + LTs & ORY + catback = 6500 shift point
220/216 + LTs + cut-out = 6500 shift point
220/224 + LTs + cut-out = 6800 shift point
224/224 + LTs + ORY + catback = 6800 shift point


So, increasing the intake lobe size will shift the powerband up... ONLY... if it has enough exhaust lobe/system to do so.

Last edited by Sport Side; Jan 11, 2006 at 01:51 PM.
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Old Jan 11, 2006 | 06:09 PM
  #40  
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So 224/224 Would Be A High Revving Powerband With Lt's Ory And Cat Back? Would It Still Be Good Power At Lower Rpms? HOW WOULD IT ACT WITH LT'S AND A CUT OUT? I AM STILL LEARNING CAM TALK. ITS LIKE JAPANESE OR SOMETHIN!
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