No revision at all.

GO CHECK THE POST, "sport."

And while you're at it, PROVE that for any given octane fuel, aluminum heads will produce more power than their otherwise identical iron counterparts.

 

Bzzzzz, WRONG.

But thanks for playing. At 100MPH there is ZERO increase in HP from automotive ram air.

But you know, I've wasted enough time with you. It's obvious you don't know what you're talking about. You read articles like the WS6 and ZX article and believe them no matter how much is proved different.

Enjoy your ignornace.

 

Never said they would. Only that aluminum permits higher compression without detonation. Again you're full of sh!t.

 

Prove it's "zero" @ 100 MPH.

It's ~ 0.18 psig @ 100 MPH.

 

Welp, now everyone can see that you're full of poop. Anyone reading this thread will see K&N's work just fine and putting ram air on a car is pointless.

If ignornace is bliss, you're on Cloud 9.

 

They permit SLIGHTLY more compression than their otherwise identical iron counterparts.

But that gain is offset by aluminum's superior heat transfer properties (which transfers thermal energy OUT of the combustion chamber, thereby LOWERING cylinder pressure).

 

HORSEPOWER...

If you aren't going to read the posts before replying, there is no point in continuing. I've already shown that any gains from ram air are non-existant. .3% at 62MPH, 1.8% at 125MPH.

Both are within the margin of uncertainly, thus making them ZERO.

 

Slightly more compression? Says who? You? LOL. :o

You're too funny. This is it for real this time. I'm finished with you and your endless B.S. L8r.

Come back when you're ready to STFU and learn.

 

I ~ agree with those numbers.

But they certainly aren't any less "uncertain" or "non-existant" than those produced by K&N air filters.

If you got a check in the mail that equalled 1.8% of your annual gross income, would you call the value of that check "non-existant?"

 

Says the dozen or so links I've posted.

And a FULL POINT bump in compression is only worth ~ 1% in terms of power gains - ASSUMING the SAME thermal conductivity. It's worth a lot less than that when switching from iron to aluminum.

 

More links. Crap when are you going to learn links don't mean anything, especially when you're quoting the sources you're quoting.

Go get Engine Analyzer Pro and check the CR HP math for yourself instead of relying on some loser internet article writer like you did for the WS6 ram air lies.

THINK FOR YOURSELF.

 

You did reference the combined gas law. You said P1V1=P2V2, which assumes a constant temperature.

 

1.8% in manifold pressure doesn't equate to perceivable gains in HP.

Show me the math that says it does. I just ran a 1.8% boost increase with Engine Analyzer Pro and there was ZERO change in HP.

 

The highest CRs I see on new, mass produced street cars is ~ 11:1.

That's with aluminum heads, 4 valves/cylinder and premium fuel.

GM is running 9.4:1 with iron heads, 2 valves/cylinder and 87 octane fuel in their 3.8.

That's a TOTAL difference of 1.6:1

 

It was not my intent to reference the common gaw law.

And I check my fluids books this AM and discovered that I was wrong.

p1V1 = p2V2 where v is velocity, but p is DENSITY (not pressure) in the shock wave formula.

So shoot me.

Would you like me to scan and post that page from my text book to prove the genesis of my admitted error?

Meanwhile:

http://hyperphysics.phy-astr.gsu.edu/hbase/pber.html

 

Again with the flawed logic. 2 COMPLETELY different engines, different manufacturers, different injectors, different head designs, different EVERYTHING, and they're following 2 different emissions standards, meeting power requirements for 2 or more different cars.

Should should no better than to try and use that to support your compression arguement.

You actually think that 9.6:1 is the absolute highest CR capable on 87? You think that 11:1 is the abolute highest capable on 91?

You'ld be wrong in both cases.

 

Which are the same gains it would show for a K&N air filter. LOL

 

How many races do you know do they maintain consistent speeds of 300 mph??????

 

You've made so many errors the Acura-TL.com servers couldn't handle the upload traffic.

We all know you make many errors. Your mistakes in this thread are just many of many many.

 

What's engine analyzer show as a percentage gain when jumping from 10:1 to 11:1?

 

5% depending on the motor with NO other changes normally associated with upping the compression. But of course non-benchtop racers know that you make other changes (eg in cam profile) when you are in a position to run higher compression.

When you have aluminum heads, you get to run higher compression. This along is more than enough to make up for the loss of heat. And without the risk of preignition you can run more aggressive timing, manipulate cam overlap to scavange the cylinders better etc. Things you just can't really do efficiently with detonation or lower compression.

But like you're actually interested in learning this.

 

How many times are you going to post the same link to something you obviously have no clue about??????

 

Harddriving and Skeedatl,

I would just like to take a moment to thank both of you. This thread has taken me from Gold to Insane Poster. A moment of silence please...

 

What I hope that people get from this, is don't trust what you read in magazines...think for yourself...ask WHY something works, not just take it at face value...and most importantly, get personal experience doing it rather than living through some magazine dork.

 

skeedatl, when I first began reading this thread, I couldn't care less about this topic. That's all changed. I have to say that I have learned a great deal and mostly from your posts. Thanks!

 

Is it?

Or do you just THINK it is?

 

I have "no clue" about the fact that a DROP in velocity (e.g. at the base of a ram air scoop) will result in an INCREASE in pressure?

 

According to Engine Analyzer Pro (which is the only way to make a material only swap since there are no identical aluminum and iron heads), it is.

In practical experience, I see significant increases in power from aluminum heads because racers can run more boost and/or higher compression (before detonation) along with all the tweaks that go along with them.

It isn't all about weight savings.

 

Ahhh, a statement we can agree on.

You won't increase the pressure higher than the surrounding air. There is no ramming effect. Ram air scoops like the ones on the WS6 aren't designed to slow the air. If that were the case they were be divergent scoops...and they ain't.

 

They put ram air on the WS6 so dumbasses will think they're getting more power. Ram air is domestic RICE! Just as useless as a shopping cart wing and 20LBS of vinyl stickers.

ALL of the HP gains in the SS and WS6 come not from ram air, but by revised intakes manifolds and the like.

 

But there are OTHER variables in those comparisons besides the head materials (such as port size/shape in the heads themselves) along with other engine mods (different intake set-up with the new heads, "hotter" cam (which produced a lower dynamic compression ratio), etc, etc, etc.


Virtually NO-ONE installs heads and keeps everything else identical (including the internal geometries of the heads themselves).

And that's the genesis of what I'll call " the aluminum head myth."

BTW:

I have Desktop Dyno SE. It also showed a 5% gain in peak HP from going from 10:1 in 11:1 in a 350 Chevy (but with the SAME heads/head material).

 

Of course you will...

You TOLD me you would a few threads back.

The "end" of the scoop (inside) as an air brake...doesn't it?

 

An increase in pressure from what???? You have failed to mention what the baseline pressure is. Does it go back to atmospheric?? The pressure across the car at 100 mph is reduced according to bernouli.

 

All the complex fluid dynamics aside, the reason Ram Air doesn't work at auto speeds is that the mass airflow at which the air is pushed into the intake manifold by the ram effect must overtake the rate at which it is being pulled in by the engine before you can have any increase in manifold pressure. An increase in static pressure in the air plenum just ahead of the filter does not nessecarily equate into increased manifold pressure. The MAP sensor in a fuel injected engine must sense the increase before additonal fuel will be scheduled.

 

Here's what HE wrote. And that more or less agrees with figures I've seen (and posted):

quote:
--------------------------------------------------------------------------------
Originally posted by Skeedatl
HORSEPOWER...

If you aren't going to read the posts before replying, there is no point in continuing. I've already shown that any gains from ram air are non-existant. .3% at 62MPH, 1.8% at 125MPH.
--------------------------------------------------------------------------------

 

It depends how you define, "auto speeds."

At 55 MPH the effect if essentially zero.

At 200 MPH is isn't.

A very mild increase in manifold pressure becomes "quantifiable" ~ 100 MPH.

http://www.vararam.com/reality_of_ram_air01.html

 

I don't agree with and never claimed that identical setups, one aluminum one iron will make the same power. Iron holds in more heat thus makes more power.

However, swapping to aluminum isn't ever for just aluminum sake. It's even rarely for weight sake. It's for compression and/or boost sake. I know I'm going to aluminum heads when I can afford it cause a buddy of mine has nearly the same setup I do, but he runs 5 more PSI of boost than I can on the same race gas 'cause he's got aluminum heads. And his heads don't flow any more than my ported iron heads do. But if I get anywhere near his boost (22PSI) I detonate like a mother F-er.

For me, for cost sake, I'll buy new heads and valvetrain but the valves will be the same size as what I have, intake, cam will stay the same.

But I'll be able to CRANK UP THE BOOST. I'm hoping for low 10's after the head swap. I want to get my buddy's heads then send them over to Joe Sherman to get worked.

 

I thought we were talking KN vs. Ram air for hp increases. I for one am not going to be driving my TL at 200 mph. This is the TL forum, right. With all this BS, I forgot where I was at for a second.

 

This about the best layman's explanation for why ram air won't work. If harddrivin can't understand this, he is totally lost. If I can add to this...

The air that is sucked in by the engine is basically replaced at atmospheric pressure minus the losses of the intake. You would have to have some pretty substantial pressure, i.e., supercharger or turbocharger, to actually "ram" air into the manifold. Would a ram air system perhaps overcome so of the static losses in the intake system to actually deliver atmospheric pressure to the manifold??? Skeedatl??? I think it is doubtful at any automobile speeds.

 

The link I posted (above) shows a 0.176 psig increase @ the manifold @ 100 MPH.

http://www.vararam.com/reality_of_ram_air01.html



Sure that's small.

But it's a lot LARGER than the delta P between a K&N air filter and a paper media filter.

I therefore don't understand how someone can support K&N's claims while simultaneously dismissing Ram Air as "myth" (@ elevated speeds).