Downforce i take vs cold air intake

[greenberet]

I ... was able to take out my Cantrell Concepts air intake scoop and fit the BPi velocity stack in its place.

Does the Cantrell air intake scoop you removed look like the Downforce scoop Hapa88 pictured in post #55? Is the "BPi velocity stack" you installed instead one of those bellmouths they call "flow stacks" on their website? Did the Cantrell scoop and does the BPi "stack" feed into the stock airbox in your car?

 

[L_RAO]

Does the Cantrell air intake scoop you removed look like the Downforce scoop Hapa88 pictured in post #55? Is the "BPi velocity stack" you installed instead one of those bellmouths they call "flow stacks" on their website? Did the Cantrell scoop and does the BPi "stack" feed into the stock airbox in your car?

The Cantrell intake scoop looks exactly like the Downforce one.

Yes, the BPi velocity stack is what they call a "flow stack".

Yes, both of them feed into the rubber "grommet" that lines the fender opening that goes from fenderwell into engine bay (airbox).

 

[charlee]

Deleted the intake plumbing from the fender and the throttle is way more responsive. Not sure why it was ever there. Having those tubes felt like the car was suffocating.

 

[Honcho]

Bringing this one back up. I'm going to try using a 3.5" velocity stack mounted to a 30-degree 3.5" silicone elbow to replace the factory snorkel. Based on all of the prior discussion from [MENTION=12723]greenberet[/MENTION] and others, I think this may help with the additional airflow needs of my Comptech cams, as well as smooth the airflow a bit. Probably won't happen until reassembly of the car this spring, but I will report back.

 

[B2FiNiTY]

Why not just get the downforce one?

 

[Honcho]

Why not just get the downforce one?

It draws a lot of water and debris into the airbox. Hopefully my design, where the air inlet is perpendicular to the side vent, will avoid that problem. Plus I can make it for like $40 lol.

 

[stallion777]

On my 1998 I have the Downforce stack system with the Downforce scoop, along side Pride high flow cats and a Pride V2 exhaust system. I've had this setup for many years and love my setup. Sounds awesome and passes emissions no problem.

 

[pvmike]

It draws a lot of water and debris into the airbox. Hopefully my design, where the air inlet is perpendicular to the side vent, will avoid that problem. Plus I can make it for like $40 lol.

This is true. I had a downforce intake on my previous NSX, and it did draw a lot of debris into the airbox and filter.

I seem to recall reading that the Gruppe M airbox (more a cone than a box) had the most gains based on dyno results per Jon Martin.

 

[Honcho]

It's important to remember that the DF/Cantrell scoop is modeled after the scoop that Honda used on its Le Mans NSX race cars in the mid-90's. Those cars were HIGHLY modified and racing at an average speed well over 100 mph. They used a wide-body rear fender that had huge side scoops feeding that intake, which led to a panel filter mated to a very sweet carbon fiber airbox. The GT2 3.0 was pushing 400 hp in that setup. Those Le Mans GT cars were designed very specifically for the unique running conditions of that particular race. I'm not surprised that the scoop does pretty much nothing for regular "street" NSXs, since the running conditions are so different.

 

[ROFL it's Waffle]

Is that a MAP sensor attached to the cover?

 

[Honcho]

Is that a MAP sensor attached to the cover?

Either MAP or IAT.

 

[Blipman]

I see a bit of talk about removing the stock snorkel or replacing it with a Downforce intake scoop here, I'm interested to know people's opinions on this:





That's slightly cheaper than the Downforce intake and I doubt the ram air affect really does anything, I'd mostly be chasing a bit more induction noise. Thoughts?


Mine is a right hand drive car so I'm not sure if some extra induction noise on the left side of the car will be that noticeable to the driver?

 

[ROFL it's Waffle]

I see a bit of talk about removing the stock snorkel or replacing it with a Downforce intake scoop here, I'm interested to know people's opinions on this. That's slightly cheaper than the Downforce intake and I doubt the ram air affect really does anything, I'd mostly be chasing a bit more induction noise. Thoughts? Mine is a right hand drive car so I'm not sure if some extra induction noise on the left side of the car will be that noticeable to the driver?

My initial thoughts, unless you're doing forced induction, your butt-dyno probably won't notice any difference. As far as extra induction sounds, the stock airbox doesn't look very restrictive (I could be wrong), but as was the case on my 2017 WRX, it had this "milk jug" attached to the stock intake which actually reduced induction noises (why would they do that to an enthusiast platform??).

But, instead of just giving you my opinion, there's a whole thread on this topic, and it seems like people love it ("Deleted the intake plumbing from the fender and the throttle is way more responsive. Not sure why it was ever there. Having those tubes felt like the car was suffocating.") http://www.nsxprime.com/forum/showthread.php/54964-Down-Force-intake-Scoop-Wow!

 

[Honcho]

I see a bit of talk about removing the stock snorkel or replacing it with a Downforce intake scoop here, I'm interested to know people's opinions on this:
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View attachment 163385
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That's slightly cheaper than the Downforce intake and I doubt the ram air affect really does anything, I'd mostly be chasing a bit more induction noise. Thoughts?


Mine is a right hand drive car so I'm not sure if some extra induction noise on the left side of the car will be that noticeable to the driver?

This is exactly what I'm considering, except without the carbon fiber bling. Basically this , plus this and mounted to the fender flange somehow.

My only hesitation is that the factory snorkel may be designed to help tune the intake pulses to aid in cylinder filling. Still trying to drill down on that, but it may be why cars dynoed without any intake actually show LESS power than with the OEM snorkel and airbox.

 

[Blipman]

You're reading my mind Honcho, that's exactly what I was planning on trying out (if my NSX was in the country!). A couple of bucks and a Saturday of messing around is easily worth it to learn something, even if ultimately unsuccessful. Let me know how you go...