Intake/Exhaust New Dyno Results

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No one asked for them, but here they are I had 3 dynos done, completely stock, stock muffler but no air inlet duct, and no air inlet duct but with the Magnaflow muffler.

Stock vs No funnel/stock muffler:


As you can see, the factory intake produces more power at drivable RPMs, but once you hit the 4k range it evens out, and without the restriction of the inlet duct it completely overwhelms the factory by the time you reach fuel cut-off. About a 11 whp 10 tq over the stock at the top end, and you really don't sacrifice that much low end, and peak values are gain of about 4 whp loss of 5 wtq. Still convinced of the short ram being plagued by "hot engine air" (or the value of a short ram at all for that matter)?

No funnel/stock muffler vs No funnel/Magnaflow:


Are you guys seeing this? The graphs look about the same. The green line is the stock muffler, and the red/blue lines are 2 different Magnaflow runs. I'm seeing about the same power curve give or take only 1 to 2 whp/wtq throughout the entire power band. So is the a straight through muffler really worth it, and is the stock muffler really that restrictive after all? It's up to you to decide.

Well there you have it folks...my dyno results. I tried to get a printout of stock plotted against stock muffler against MagnaFlow muffler but alas, we ran out of paper Shoulda printed it first. This was done with the hood closed, back to back runs, air temperature of 78 degrees and humidity of 72%. Different people will interpret these results differently, you must interpret this for yourself. But it sheds a great deal of light on where the restrictions are don't it.

I also walked away with a free Boxster S exhaust They were going to throw it away but I said I'll give you 5 bucks for it, but they said that I could have it for free since it was going to be trashed anyway. Now if I can just find a way to fit that massive thing somewhere...maybe I'll put it in my trunk and drill holes out to the bottom of the bumper

[00GTZ00]

Man it still blows me away about the difference between the Fed and Cali spec cars! Man I need to start getting my engine mods and get them dynoed with you Peter so we can see how the Fed cars react to mods! Maybe after I get my CAI we can meet up, get my car dynoed to see exactly how much a CAI vs. Stock really gains, and go out trying to find some races afterward!


Ok so if I am reading this right. the diff in Hp from stock to No funnel/magnaflow was a gain of 4.1 hp and a loss of about 4 ftlbs of torque. uhmmm very interesting...


I am still going with trying to replace the cams first with at least a stage 1 from RPW. That way you will see more from the I/E...but eaither way that you do it I think that a cam upgrade needs to be within the first few mods tha tyou do to start seeing any real gains...

But that is JMO!

[cdaw2001ES]

The ecu needs time to learn after a mod is made, particularly on the intake side. How long (or how many miles) were between the stock air scoop/ no stock air scoop dynos?

[00GTZ00]

the ecu changes for the CAI as soon as you start the car. resteting the ECU has no effect except for a SOTP feel..

[cdaw2001ES]

on the I4. The fuel curve is constantly predicting stoich, it's prediction calculations are based on stored, and constantly updated memory tables and check by the odbII system. At 80% throttle or more it switches to a different memory table, and no longer attempts stoich, I'm sure ripp could explian it better
But by using a A/F guage you can watch over the course of an hour of driving - after reseting the ecu, The curve is constant refined until it settles in to a good stohic dance.
Wen I first went s/ram & header, I was not touching the rich indicator, within a day - it was back bouncing all the up. It actually likes to overcompensate a bit on the rich side.

This has been my expirence, it's totally different for the v6, I'm not sure what slowpoke gots, besides an evo , But now I'm assumin its a 6. so my statments can be ignored

[Auto-9]

The ecu needs time to learn after a mod is made, particularly on the intake side. How long (or how many miles) were between the stock air scoop/ no stock air scoop dynos?

00GTZ00 is right, our cars compensate immediately. However, you are also partially correct in that the computer will learn over time to see if its adjustments are correct, but it occurs much faster than most realize. To answer your question though, if you look at the date you'll see that completely stock without removing the inlet was dynoed in February of this year. Thus I estimate about 6-8 thousand miles between the dynos. More than enough time to learn, regardless of how fast or how slow our ECU supposedly is.

[onlyphases]

What does slowmaster mean by "no funnel" ??? I dont understand that terminology

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<div class='quotetop'>QUOTE(onlyphases)</div><div class='quotemain'>What does slowmaster mean by "no funnel" ??? I dont understand that terminology</div>

If you look at the factory intake, you'll see a funnel looking thing that sits on top of the radiator that routes air to the airbox. That's the funnel that I am referring to. On my car, I removed it to test the theory of it being the major restriction (and seeing the results I'm keeping it this way).