Stock Maf Limits
 

I figured I would post this up in a new thread instead of burying it in my build thread as it will probably be useful to a bunch of you. Running the 2.5" boost tubes the stock MAF will max out right around 10.5 PSI. Anything higher than this is quickly starting to exceed the capabilities of the stock MAF. Which at about that boost the car puts down ~530hp. I am currently trying to take the stock block further just to see what it can hold.

Hope this helps someone going boosted and trying to figure out their air needs.

Very informative was debating between 2.5" or 3" on the intake tubes...

The Fast Intentions Intake tubes are indeed 2.5".

They have run them past 650, and within safe limits. From what I have heard, they can take up to 750hp(theoretically) on their particular kit, no doubt 700 is within sight. I daily drive north of 610 on 12.6psi. On a 2.5" intake tube.

Your mileage may vary, maybe it is based on the kit setup, but they have found the stock maf easily capable of 650 without a reason for concern!

That's aggressive as hell, even on E85. I like your style! :excited:

You sure they dont flare up to 3" at the MAF? Not sure how you could anymore air though this 2.5" it just wont happen. I would be curious to hear any feedback directly form specialty Z.

For me right at 10.5PSI my MAF voltage is around 4.60Volts getting very close to the 5 threshold and IMO at the limits of the sensor.

Maybe altitude is playing a role here. All I know is I am most defiantly maxing out my maf running over 11PSI.

Mitch...the tubes in which the MAF's are housed are 2.75" with the BP turbo kit.

I think F.I had 2.5" tubes to begin with, and found that they max out too early. They had switched over to 2.75" tubes a while back.

My mistake Sasha. Im curious as to how the FI kit can run over 10.5PSI and not max out their MAF.

Thanks for the clarification I thought they were 2.5s.

What is your MAF voltage at 10.5psi?

~4.6-4.7 at 10.5PSI

Unless your kit is just moving that much air on the top when compared to the 2 smaller turbos?

Usually tuners push the sensor voltages deep in to the 4.9V's, and can get the additional couple of psi.

It'll be interesting to see where the voltage will be once I make those 3" charge pipes for you.

My MAF curve is your typical exponential one and when I log what uprev is reading for its conversion to flow rate it pegs at a constant number after 10.5ish telling me that the sensor stops differentiating between an increased airflow. Ill play with it more this week.

Thanks Sasha.

This could very well be the case. Either way, what I have in there suits me well until about 700hp.

I personally don't really care whats in it. If its functional, reliable and powerful, it can be 1" or 6" haha! That's why I pay Tony and Seb to do it for me! :tup: Either way, it's cool to hear some fun plans in the works for both BP and F.I. kit owners. My 2.5-2.75" tubes won't be around much longer...unless someone finds a way for them to support much much more than 700hp.:tup:

Stay boostin' my friends!

I daily drive north of 610 on 12.6psi. On a 2.5" intake tube. NWO THATS A SICK statement ( In a good way) LOL GODANM!!

Well I hope the BP tubes can handle 14-15 lbs cuz thats what Ill be running in the next couple of weeks.

Dare I mention that we are also using puny gt28rs turbos, 2.5" exhaust, and a stock block?

BUT yes, daily driving a 600+hp/550+ftlb 370z is an absolute BLAST:happydance:

Back on track, my tubes are DEFINITELY NOT 3" at the maf, measured them today, outside diameter is quite a bit short of 3"...if that helps any! I dare not pull anything apart, I have no leaks, no concerns, again I will leave that to Tony/Seb unless it's a dire need type of stuation.