Tis the nature of confused people to confuse those around them.... this could become a real problem. And Albert Einstein is likely rolling in his grave 13.88 times a day.

-Mindgame

 

I was agreeing fred

and you basically agreed with me agreeing to you

And yes, the 4--->3--->4 would be a smooth transisiton, not a "butt" - i'm sure thre a bazillion variables we could include

so 4-------------->3--->4------------> will more than likely have more flow than

3 all the way acorss (but then there are issues with how the 3'' meets the 4'' and stuff.


and the highway was in agreement again with "duh think about it for half a second"

2 three inch collectors meeting a 3 inch catback vs 2 three inch collectors meeting a 4'' catback


my basic agreement point was "think about it for a second"
but guess it wasn't all that clear


Let me summerize-

I agree fred

 

ROFL here.

"Men who borrow their opinions can never repay their debts."---George Savile, 1633-1695

 

LOL

"Only two things are infinite, the universe and human stupidity, and I'm not sure about the former." - Albert Einstein

-Mindgame

 

alright, enough picking on Trey here.

On the manifold topic, there is easily alot of power to be found in LT1's through the intake IMHO. I would easily take another 20cfm and longer runners on a LT1 vs another 20cfm, both would be even better. The TQ gain would be worth it more than the HP gain, but the additonal TQ you would really feel.

Bret

 

Oops, I made another math error. Let's be honest - I never learned to count past 10

I have no idea where the standard of 28" H20 comes from, but it's damn close to 1 PSI so I imagine that has something to do with it. Either that, or the first flowbench designer had a broken-off yardstick sitting around.

Yep, but I'm guessing that tuned runners would require more plenum volume, and that of course would have made the packaging issues worse for the 4th-gen F-body. If you believe what Lingenfelter had to say on the topic, the Accel Superram was a big improvement over the stock LT1 intake (but I'd be making the same claims if I was trying to sell you a $1K intake, too).

It's not that I want to slow down the exhaust gases; it's that they're naturally going to loose velocity as they cool, and therefore they're going to require a larger cross-sectional area. At least that's the way I understand it; hopefully someone can correct me if I'm wrong.

That's because I like it when guys like you speak up and either tell me that I'm right, or inform me that I need to lay off the crack pipe

 

As the gasses cool down, they become more dense, occupy less volume. To get the equivalent pressure drop with the smaller volume, you would use a smaller pipe as the gasses cool. If you just leave the pipe size alone as they cool down, they will just naturally slow down and produce less pressure drop. Can't think of a reason why they would need a larger cross-sectional area.

I don't think Bernoulli is relavent to this.... isn't that the theory that tells you the pressure perpendicular to flow direction is reduced as velocity increases.... not a "pressure drop" issue?

I always go back to George's car.... 1,125HP, Hooker LT's into a 3" Y-pipe into a 4" Mufflex cat-back, with a single 4" pipe out of the exhaust. But George likes the "stock" look, so he cuts the little tiny tip off the 30th SS's original SLP 2OTL exhaust and welds it to the end of the 4" pipe out of the muffler. Looks stock. Still make good HP. But it also pushed the gas velocity way up, as demonstrated here.

 

From what you said Trey, it seemed like you read it completely backwards. A 3" pipe is going to provide more resistance than a 4" pipe, so even if a 3" coupler in the midst somewhere , the rest of the exaust at least is free flowing.

What I think Fred was getting at though, is if we are using a Hooker LT example, you have two 3" collectors going into a hopefully dual 3" to 4" Y pipe hooked up to your 4" exaust.

 

wow-

I just re-read what i wrote-

I thought 4-3-4 > 3-3-3 but for some reason i wrote will NOT flow as well

now i see where all the confusion is coming from (and jokes at my expense ) I re-read it twice quickly but i guess i read what i thought i wrote over again, not the actual words.

I was sitting here trying to figure out why everyone was disagreeing. I just couldn't picture the 3-3-3 flowing as well as a 4-3-4

I REALLY need to be more careful and I feel rather stupid right about now...

my appologies

 

Is there a way of measuring velcocity of air after it goes through the cylinder head and into the chamber? I don't mean cfm. Maybe Swirl Velocity or Swirl RPM??

 

We are getting off this topic, but yeah there are swirl meters for flow benches.

Bret

 

My understanding gives credit for this std. (28") to S. Yunick. The reasoning was that using this std. to compare head port flow, would result in a more accurate comparo to actual/usable gains experienced on a dyno.

Da mind is a terrible ting.

 

I'll go along with that. Smokey claimed that at less than about 26-28 in H2O he couldn't find small changes, and above that it didn't make much difference.

Also, 28 in H2O is just about 1 psi, which is near what a max. performance engine pulls around hp peak.