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comp 216/220?

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Old Sep 29, 2004 | 02:57 PM
  #51  
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How do they get 242* stuff into that small of an 'area'?


*thrown for a loop on that one!*


I'm lost by your comments, but heres a post by J-ROD, if you'd like to look into it a bit more. I was using it as a reference to valve event comparisons.

J-ROD writes...
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Old Sep 29, 2004 | 03:01 PM
  #52  
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Originally Posted by SportSide 5.3


I'm lost by your comments, but heres a post by J-ROD, if you'd like to look into it a bit more. I was using it as a reference to valve event comparisons.

J-ROD writes...


I'd just expect VERY different VE's based of the large duration...

I can't comprehend this stuff at the moment. Give me a few. Days.
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Old Sep 29, 2004 | 09:50 PM
  #53  
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Originally Posted by SportSide 5.3
Ok, I'm not familiar with that logic, but I have heard of it. Where the larger exhaust durations creating more tq for a longer stretch of the rpm band. Correct?
yes.

Originally Posted by SportSide 5.3
But, isn't it more important to match the head flow characteristics to create the camshaft? For ex.
Stock 5.3 Head Flow #
.100 = 85.7%
.200 = 72.6%
.300 = 67.6%
.400 = 69%
.500 = 74.7%
.550 = 76%
.600 = 76.9%
For CID under 400, 75% exh ratio to intake dictates a single pattern cam. For every % point over you need to crutch the intake 1/2 degree of duration?
it really depends on which side the restriction is on. intake or exhaust. would need to see the actual flow numbers for each side to determine the restricted side. using the rule of thumb you have there, the ratio is UNDER 75% most of the time. so, crutching the EXHAUST side is in order.



Originally Posted by SportSide 5.3
I agree. Just a misunderstanding.
I was referring to duration (reverse split, standard, ..)
Most enthusiasts go with a set of long tube headers, exhaust work, and then leave the stock intake manifold in place. Here we have a very well flowing exhaust and a not so good intake. I was getting at, whats the point of a large regular split (HELPING THE EXHAUST) when we don't need it. We need the duration between the valves to favor the intake.
refer back to above. reverse split cams work best in turbo/blower applications. i worked with a company that owned ERSON CAMS from 93-98. got some good schooling there. now, working WITH vinci, i'm learning more about the latest accelereated lift technology. (it's nice knowing the right people. and no i do not work FOR them.)

Originally Posted by SportSide 5.3
The goal is to balance out the air coming in, and air being released. Obviously they are not equal. So, you find where your lacking. Obviously we dont have much options to improve incoming air.
Ex. A man breathes thru his nose, and exhales thru his mouth. His nose is plugged. So, he breathes LONGER thru his nose, and shorter thru his mouth. This creates an equal exchange of air. (his nose was plugged)
here's the old adage that works best. " a motor can't get more in, if it can't get it out." basically work the exhaust first. looking at exhaust systems. there's a thing called 'scavenging effect'. as the exhaust pulses come out of each cylinder and travel down the pipes, it creates a vacuum behind it. this in turn pulls the next pulse out of the cylinder. and with it pulls more of the burnt gases with it. now, what this does with the intake side is allow for more fresh incoming mixture into the cylinder. which in turn creates more power. one to consider is that exhaust pressure built up due to exansion. the intake charge is actually smaller per square inch and needs all the help it can get to be pulled into the cylinder. intake mixture is at atmospheric pressure. exhaust isn't.

Originally Posted by SportSide 5.3
This is where single pattern cams dont make since. Our motors aren't equal so why put a (220/220 or 224/224) exc.

If I am off anywhere, please redirect me. I'm here to learn to.
hope this helps to shed some more light as to why the split in intake vs exhaust duration is the way it is with the VHP cams. for a reference look at the c5 test car when they intalled the 047 cam in. the torque shot up dramatically. test 4 vs test 5 http://www.vincihighperformance.com/...ARPARENT2.HTML
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Old Sep 29, 2004 | 10:25 PM
  #54  
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30 rwhp and over 100 rwtq?
seems like the time slips should be higher
he trapped higher maybe he had traction issues?
seems like it would've gained more

test 5. 12.368@111.13 with cam 342/428.1
test 4. 12.42@109.34 before cam 312.9/325.5
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Old Sep 30, 2004 | 08:51 AM
  #55  
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Yeah, when they went with the 047 cam, they had traction problems... The reason the 055 is faster at the 60' is because it move enough lowend power upwards, so that it hooked easier.

The only thing about the dyno's - they're not all consistant... The first handfull are all 2nd gear pulls, the 047 is in 3rd and it looks to be unlocked... so with that 2,800 stall, I believe that's where you see the huge torque numbers.

Still though, the cam is very torquey.
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Old Oct 1, 2004 | 12:55 AM
  #56  
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yes the 047 is a street cam. design for lots of low to midrange torque. these times were on 18" BFG DRs. they are keeping this car as much a street setup as possible. if they had slicks, the car would have easily been an 11 on the 047 cam.

if the converter was locked, you would've seen even higher torque. and they don't lock the converter. when racing or at WOT, the converter isn't locked. so, why show it that way?
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Old Oct 1, 2004 | 02:36 PM
  #57  
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im all about getting more area under the torque curve. my research has just begun and so far vhp sounds great....
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Old Oct 1, 2004 | 03:10 PM
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also, VHP has made another cam just like the 047. same duration, just more lift. the 062. for those wanting just a little bit more.
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Old Oct 1, 2004 | 03:35 PM
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I'm so mad they came out with the higher lift version! I know it was an option for a while, then they took it down... I would have gone for that if it was available.

At the time I called, Roger either said they'd take a little while to make, or they'd cost a little more to make...

AHHH. What's .020 on the lift, anyway...
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Old Oct 1, 2004 | 05:33 PM
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so will the added lift move the powerband upwards at all? got your pm mark...dude, if i only had some cash
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