S'vette

I have some questions about various performance parts and how they work and help our car.

1. What is the difference between the stock air box and the after markets? They look pretty much the same design. I've heard something about DOD with the stock one.
1a. So the rsonator prevents harmonic waves, which causes air pressure, which is bad for flow? If so how do aftermarket ones get around this?

2. Ported throttle bodies, do they require a tune afterwards?

3. Tunes, will our car still have the capability to learn from minor mods like CAIs, TBs, etc. put on after an aftermarket tune?

4. Does VVT give our car performance gains? Would going cam be better off with a non VVT cam? If so why?

Thanks all.

dovervold

1. Aftermarket CAI's are just going to flow a little more air. I have had an AFE on for 10,000 miles and like it. As a stand alone mod it doesn't add much for HP, but I do like sound of the intake rush. Most people seem to think a CAI on the LT1 is worth the money.

2. Negative, no tune required. You need to be careful when selecting a ported TB. Some of reported problems related to idle speeds. I have had a Weapon X ported TB for the same 10,000 miles and it has performed well. Again, not much here as a stand alone but adds a little if you start a build.

3. I don't think so. Once you go the custom route I think that is where you are going to stay. I have had 3 different tunes: 1. Diablo 93 octane AFE tune. Car ran good and performed better than stock for sure. 2. DiabLew did a custom tune with my Diablo Intune. Marginal gains but again, the car ran very well and pulled pretty good. 3. I ended up finally going with LG Super Pro's and a ported intake from Weapon X, installed, tuned, and dyno's by Doug Rippie. Definately the way to go if you want a nice bolt on car that sounds bad axx and pulls strong. Very happy with the performance and sound.

4. VVT allows the valve timing to adjust with speed, so you get excellent performance all the way along curve. The reason to delete VVT is so you can go with a bigger lift cam and chase the gains in the higher RPM range. But you give up some low end Torque.

One of the best things you can do is try to lower your IAT's so you don't give your HP power back with heat soak. So many people spend big money on mods and don't realize that ECM is going to pull timing when the motor gets hot. Send me a PM and I will give you a solution for IAT's...

Good luck man, let us know what direction you end up going

S'vette

Thanks for the response to my questions. So did the TB give you better throttle response? Not really looking for HP out of it, just wondering if it would help in 0 to 60 and 0 to 100 times? Im looking to improve my low to mid range power mostly, thats why I went with Mid length headers as they are suppose to help in that area. So how do aftermarket CAIs get around the harmonics that a stock resonator use? Thanks again, PM is coming too.

dovervold

Yes, ported TB and CAI should work well with your mids. Another thing to look at for throttle response is something like the Vitesse throttle controller. Remember, you are at the mercy of ECM to open the throttle blade. So even if you mash the throttle to the floor, the ECM only gives so much throttle body. The Vitesse will fix this and I have heard good things. And apparently you get like 4 different settings. The other cure is going with a Diablo Intune. The cool thing is you can do some data logging with the Intune, and for $185 Lew will write a custom tune for your exact car. That is the route I went before I decided to go with Long Tubes and a custom tune and dyno.

For the harmonic question, you need someone smarter than me to answer that question.

Good luck

S'vette

I got a dyno tune done when I did the Mids just to see what the difference was with and without a tune. So I should be able to adjust the throttle response within the tune too right? Just thought a TB and getting the tune adjusted might be a better all round option. I am curious about the CAi because I dont want to spend that kind of money on a CAI when I could just do a drop in, but from some reading I saw the harmonics thing and I thought I saw something about the stock intake box and DOD?

S'vette

The primary purpose of the air intake resonator is to inhibit pressure wave harmonics, which causes air pressure in the engine and restricts the amount of airflow through the RPM spectrum. In effect, the air intake resonator, via its expansion chamber, slows down the air emerging from the engine. This reduces the engine intake noise and increases the amount of horsepower available.

So how do aftermarket CAIs get past this if anyone can help?

BJ67

I have a hard time understanding the resonator built into the OE intake track would increase HP. All the AM intake's do not have a noise cancelling intake quieting feature.

S'vette

that's why Im wondering how the harmonic stuff doesn't effect the AM ones if it does the stock ones.

BJ67

Anything that quiets noise should also interfere with flow. The AM units only care about flow increase, hence no sound control features or anything that hurts the flow of air IMO.
I truly believe any tweaks no matter how small to help or unobstruct air flow helps.

S'vette

I understand the better, smoother, and more air flow, but the articles Ive read said the harmonics interrupt the air flow and this causes not so smooth air flow which takes away HP. So the resonator helps break up the harmonics which is suppose to help air flow, if all this is true. So not sure how th AM get around this if they do. Just curious as the AM can be expensive.