When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
This is the vac gauge I use. It plumbs right into the nipple of intake. It has a vac reading on side and a re set button. You can see if any/how much vac is pulled. I go WOT on the street so its real world, then check gauge. I do this at all rpm points until I see it pulling vac or not at that rpm to see where restriction point is. As mentioned previous filters I tried started pulling vac at 7k rpm. Bellow is the filter I tested/now use to insure no restriction- vac. Notice the measurements. It just barely fits in the stock gutted factory box. It probably has 1/3 or better the surface area over the stock cone filter, and that's no small filter. The stock size KN drop in filter pulled no vac either, but that was without use of a velocity stack.
I put a restriction gauge on my car back in '12 to help me know when to change my air filter and I was surprised I got 8" with a stock filter. Took the air box lid off and had no restriction(but got hot air) so I cut a 3 1/2" hole in the end of the air box and ran some 3 1/2 hose down to the fender well, no more restriction. Air filter was changed at 90k miles due to age not miles, even at 90k miles it showed no restriction.
Here is my post on the air filter https://www.s2ki.com/forums/s2000-un...ilter-1163927/
Here is where I mounted my guage on my '06
^^^ You gave me the idea to run one of these vac gauges. Didn't even know they existed until I saw your post. I used it to tune my own intake and perform a multitude of filter size testing, also doubled as a plug since I dont run a breather or air injection on my intake. I didn't see a vac with stock gutted box and kn drop in. Not surprised to hear there was with a completely stock intake and paper filter. This engine pulls a lot of cfm in vtec.
I completed my intake today. I did a double step like I mentioned earlier in this thread!
I didn't get any in progress pictures, but my buddy who has a small youtube channel filmed the whole install, and I'll be sharing it here when he posts it up. But for now here's what it looks like in the engine bay, and mocked up on my couch (prior to being trimmed to fit of course!)
I have an 07, so the stock TB is 69mm, or about 2.75" I then went to 3" straight off the TB, 90* turn to 3.5" tubing, another 90* turn to a 4" pipe that runs horizontally out into the fender well, another 90* into a small 4" pipe directed towards the front bumper, into a 6" velocity stack and 6" AEM dry flow filter.
Compared to my OEM intake arm (without the airbox) that I was using for a few hundred miles before this, I can say the heat soak is definitely gone
I plan on using my dyno software, and doing some real world, back to back street dyno pulls to try to get some before and afters. I may pick up an airbox too so we can have a true stock vs custom intake comparison. Butt dyno just says the powerband feels flatter and more consistent, but the SOUND is crazy. Instead of that typical Vtec K&N short ram growl that we all know and love, this gives that same growl, but with this background deep ROAR that sounds terrifying and amazing. I'm in love with the sound of this huge tubular intake, very intimidating. I'm enjoying it as of now, I'm glad the install went mostly smoothly, and hopefully in the near future I'll have some dyno results to show what gains were had!
Last edited by liquid_helix136; 07-30-2017 at 08:25 PM.
I have a PasswordJDM intake that I picked up for a very reasonable price. I am curious if any of you guys have switched between the two or have any insight? I am doing an NA build for my AP1 TT car and every bit of HP I can find I will need it.
So I wanted to update this thread regarding the long tube intake I put together.
I took my intake out the other day to my super secret tuning spot to make some street dyno runs using Flashpro datalogging and Virtual Dyno. I ran the long tube intake against the stock intake arm WITHOUT the airbox. I know this isn't ideal, but it's all I could do currently. The filter sat in front of the engine, and is similar in design to the K&N intake, but with less heat shielding. I was able to make some consistent runs and picked out the average between each intake.
It was 89*F outside and intake temps would skyrocket up to 150-160 with the stock intake arm, while with the CAI, intake temps maxed out around 136, but with movement, quickly dropped to 110 or so.
Anyways, these runs were done within about 20-30 minutes of each other, there was zero tuning changes done. Also, add about 1 point to the AFRs to get an accurate result, the software reads about 1 point rich.
You can see there was a significant increase in airflow with the long tube intake, with a consistent 8-10whp gain across the board, and about 20whp gains around 6k rpms!
Take the absolute numbers with a grain of salt, these aren't calibrated with any actual dynos in the area, but the main takeaway is the change in power and jump in AFRs due to increased airflow.
One variable I want to mention is the AIT were about 30*F warmer with the stock arm intake, which could definitely attribute to the large gains with the CAI, but I decided to not try to correct for this, because one of the added benefits of a CAI in the real world is consistent and lower AITs, which result in more consistent, higher numbers.
So I wanted to update this thread regarding the long tube intake I put together.
I took my intake out the other day to my super secret tuning spot to make some street dyno runs using Flashpro datalogging and Virtual Dyno. I ran the long tube intake against the stock intake arm WITHOUT the airbox. I know this isn't ideal, but it's all I could do currently. The filter sat in front of the engine, and is similar in design to the K&N intake, but with less heat shielding. I was able to make some consistent runs and picked out the average between each intake.
It was 89*F outside and intake temps would skyrocket up to 150-160 with the stock intake arm, while with the CAI, intake temps maxed out around 136, but with movement, quickly dropped to 110 or so.
Anyways, these runs were done within about 20-30 minutes of each other, there was zero tuning changes done. Also, add about 1 point to the AFRs to get an accurate result, the software reads about 1 point rich.
You can see there was a significant increase in airflow with the long tube intake, with a consistent 8-10whp gain across the board, and about 20whp gains around 6k rpms!
Take the absolute numbers with a grain of salt, these aren't calibrated with any actual dynos in the area, but the main takeaway is the change in power and jump in AFRs due to increased airflow.
One variable I want to mention is the AIT were about 30*F warmer with the stock arm intake, which could definitely attribute to the large gains with the CAI, but I decided to not try to correct for this, because one of the added benefits of a CAI in the real world is consistent and lower AITs, which result in more consistent, higher numbers.
The only thing this tells us for sure is that hotter intake temps make less power and cooler intake temps make more, but we knew that already. Tells us nothing about possible increase in flow by the design with these two intakes. It is a shame you could not incorporate the stock intake box with the stock arm, that would have told us something.
There are compounding effects with IAT changes on fuel tuning as well which reduces power even further. So its not just consuming less air, but the engine is also running richer. Again this test shows us nothing about intake design for better flow. It does tell us that removing the stock intake box is a very bad idea.
Last edited by s2000Junky; 08-04-2017 at 11:12 AM.
I tried to get it to fit post new intake install with removal of just the 3" pipe, but it didn't fit. I want to get solid results regarding the design against stock though, so I may pull everything but the horizontal pipe and make pulls with minimal variance in AITs to yield optimal comparisons.
One thing that can definitely be drawn from this test though, is that CAI does wonders in stabilizing and keeping AITs down.
07-01-2017, 05:55 PM
