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Discussion Starter #1
If you were to put a Popcharger, a 3'' intake tube, a larger diameter TB, and a plenum on a Z is that too much incoming air? I just saw a thread about someone saying with a Popcharger and TB, he added a 3'' intake tube and lost power. Anyone know?
 

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From what I understand, there's not really a such thing as too much air...technically.

However, in forced induction systems (ie. turbo, supercharger), too much air can cause detonation, which is normally fixed with a higher capacity fuel pump.

In a stock (or near stock) car such as yours, the stock fuel pump and ECU should be able to make up for the extra air by pumping more fuel into the injectors.

If that individual is seeing horsepower loss, it's probably not because he's getting too much air. Again, that is unless he's running a turbo or SC without an aftermarket fuel pump. It's more likely that his Pop Charger, and plenum are are not jiving with each other, which is sometimes caused by brand mismatch. Not that the brand name has anything to do with it, just that each brand is designed to be most effective with that company's components. Therefor, if you use the JWT with, say, a Crawford plenum, it's not inconceivable that they may not work well together.

Of course it's always possible that he damaged the MAF sensor while installing the Pop Charger. The MAF right there on the end where you have to do a lot of the work during the JWT install.

If nothing else, I haven't heard of anyone having that issue, and there a lot of people here that have similar setups.

Someone correct me if wrong on this.
 

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Dyoned lower than stock with a Weapon prototype....A/F mix was lean, ergo, too much air. CAn happen. We changed the intake tube so that we could use the stock MAF sensor housing. This helped the lean & low #'s. Still waiting to dyno the new intake...

All that air has to have fuel mixed with it, & a quick way out...
 

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It's simple: If you force more air volume into the engine, you must have a way for it to exit efficiently. Therefore, you need to upgrade your exhaust system to accomodate that increase in air volume/intake.
 

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There is a little more to it than what has been said so far.

Good intake design is keeping airflow speeds up while not restricting flow. This is the only way to get better than 100% volumetric efficiency on a power plant. The goal is to get the column of air moving at a constant rate through the intake, this in turn ends up working like a siphon to continue pulling in air while most of the valves are closed. Then when the valve opens, the air is under pressure (yes this is normally aspirated) and begins to fill the cylinder immediately, this combined exhaust scavenging and the intake stroke sucking can actually fill the cylinder up with more than 100% of the volume.

Now take a poorly designed system, air is lazy and not really moving in any direction, suddenly a valve opens and the piston is nearly a third down the bore before it can create enough vacuum to get the stagnant air to head in its direction. In this case you won't even get 80% VE.

Chris
 

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Discussion Starter #6
So Hypersprite, what would you recommend as far as mods to affect the incoming air? I already have my exhaust side of things in mind, but should I just stick with the Popcharger and a plenum, or add the TB and larger intake tube as well?
 

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I've heard that getting the larger TB is not so good for the Z. A larger tube might help funnel the air, though. Like Hyper said, as long as you get a good airflow, you should be alright.
 

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The stock TB only opens 85% without a reflash, so if you are looking to spend 600 or so, you might look there. It will also raise your redline so you can get more out of the better breathing and remap your fuel.

Also, the lower plenum for the 05 35th is now available and looks like it addresses the shortcomings of the earlier lower plenum.

The unknown here is if the stock TB or intake tube is fully utilized. Without being able to measure the speed and volume of the air moving through the entire system, it is all just guessing and trial and error.

On the "larger tube" idea, you need to look at how it is attached as well, if it starts out big and gradually gets smaller to match the TB, it might actually help. If it steps down to attach to the TB, the step may cause more turbulence than the extra sizing might have helped, further depending on the step, you may actually get less overall flow.

Chris
 

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Actually, you don't need to spend $600 to get the reflash, just get the L-Spec. It lets the TB open 100% at WOT, removes the rev-limiter and speed-limiter.
 

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Discussion Starter #12
So basically, no need for an aftermarket TB. That definitely helps me decide on my mods. I think I'll just go with my Popcharger and a lower 2005 plenum.
 

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[/quote]
What are your HP goals? If it's 295-300rwhp, definitely get the TB. Every little bit counts.
 
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