Correct, but there are kits out there that come with 2.5" tubes.

I used 2.75", which was sufficient for stock block power at the time of development. However, it seems like customers are starting to push more and more power, with higher boost levels. I have built a couple of sets of 3" pipes in the past for those that intend on building their engines...but for the most part the 2.75" tubes will do the job.

The V-2.0 will come with 3" pipes, and that should be more than enough to push the stock block to it's absolute limits. Upgraded MAF sensors are available with the kit too, for those that build these engines and want to run 15+psi of boost safely.

Why dont we just make 3.25" tubes? :stirthepot:

Good question, I would think increasing the piping to much just in one spot will change the flow profile of the tubes. Not to mention you slow the velocity of the air down as it hits the larger boost tube only to ram it as fast as you can back down to 2.75" and through the TBs. If you could find a way to get bigger throttle bodies (maybe off a titan? have no idea if nissan has larger TBs) then you might be onto something. lol.

I have never personally tried it, but I am under the impression that the loss of resolution at lower airflow can make it difficult to tune low-load areas of the map. Where that comes into play, I am not sure. But I think the 03 Cobra guys start with like a 3.5" MAF tube and upgrade to like 4-4.5" since they are pull-through.

I wonder if there could be an easy way to just sort of restrict how much air actually passes through the MAF sensor, rather than having to put it in a larger tube?

I dont think you would have that issue myself. At lower airflow the car is running in closed loop anyways so the MAF is not really watched at all anyways. All you would have to do if you were having issues at lower load is just pull the car out of closed loop later and let O2s deal with the resolution down low.

It was discussed a bit earlier in here that you can just move the maf closer to the wall of the tube and because you assume laminar flow through the pipe the velocity of the air moving near the wall will be less.

I think if you go to big you will cause turbulence in the piping since they are relatively short to begin with and you need that smooth flow to be able to accurately meter it.

Also on a side note your fuel kit is working awesome. It holds 65+ PSI all day under boost with no signs of slowing down. All this wouldn't be possible on the stock system.

these are the 3in charge pipes i made with the tall maf slots sorry there not powder coated yet and with testing last night and some today( on 24hr duty right now) there running 4.2 volts at 12 psi. i'm not running an exhaust right now.



http://i1291.photobucket.com/albums/...ps11izuwuz.jpg

http://i1291.photobucket.com/albums/...psdda46dwe.jpg

http://i1291.photobucket.com/albums/...psdds1iknw.jpg

Nice work! How tall are those standoffs?

So if the sidewall slows down the air.....what if you made that sidewall slow it down more. What about roughing it up?

when i get home i well check how tall the are...i know they put the opening of the maf at the very edge of the pipe

Very nice! That should give you more headroom than me.

well see i got to play with the tune some more...i and stop turning up the boost i started at 7 and started going up...but i hope this sloves the problem

here is a pic of the pull from my base tune on 10psi and you can see my MAF's don't get over 4.12 volts.....

http://i1291.photobucket.com/albums/...psrfftzggu.jpg

How tall are those standoffs again? And what were your volts at 10psi before the mod?

In tall and idk cuz this was my first configuration..I know one thing that helps is the shright part be4 the maf