General Supercharger Thread

Looking at the MAF from TurboKits (this thread: https://www.tundras.com/threads/turbo-charging-a-tundra.115951/page-27#post-3537022) they appear to have made a MAF that drops the voltage by ~30%:

https://www.turbokits.com/2007-2021-tundra-5-7l-high-flow-mass-air-sensor-maf.html

That's based off the values HP Tuners gives for a stock tune, and the little sheet that TurboKits has a picture of (for whatever reason they wouldn't just tell me that 30% value outright).



Punching some numbers it sounds like a lot but is not as much as I would've thought. Since the MAF voltage is based on intake area which is a square function of radius, you actually get a 30% increase in flow roughly each size the intake is bumped. So the Magnuson 4" is a 30% increase over the stock 3.5". A 4.5" is a ~30% increase over the 4". 5" is a ~30% increase. Essentially a 0.5" larger intake is around 30% more area for the ranges we typically see.

To some extent the TurboKits MAF makes sense at $175, but you're also not getting a larger physical intake. The Magnuson 4" might be a better buy if you have a stock intake, it's more expensive but not a lot more. A 4.5" or 5" intake is guaranteed to be significantly more expensive though and custom made, so at that point their MAF probably makes sense if you don't care to physically make the intake larger or if you still want to keep the stock style airbox. Food for thought, and very cool to have this as an option. Either way it'll need a tune update the same as an intake would.

 

So a 5" intake and their maf would be even better. But also note this is on their blow through wonder how much that will effect us? Should I get one lol

 

Youre only hitting 5psi over in flag?
In wot ill get 9 over here in pinetop

 

Better is a relative term but I don't see it hurting anything. And it should be as easy as rescaling the MAF.

 

Agree with @NatesNightMare that sounds low. I thought @Wynnded was also in the ~8psi range.

 

So thinking of this boost referencing reg thing. How much psi can that handle? Since this wasn't originally designed to handle positive pressure. In terms of the stock regulator

 

Something like that. Definitely not hitting >8psia. I'll have to go do a test run to be sure

 

Thanks for looking into it! I'm good for now. Gotta stop myself for always looking for something else.

 

I had the bung installed Saturday for the PSB1 in the BMW, AFR reads 7.4 at idle & 22.4 at wot. Forums say it's a bad ground so I ripped the dash apart (no fun on this car) and ran the ground to the freaking body (a bolt holding the gas pedal down) and no change. Anyone seen this?

 

Reading comprehension...was going to reply then saw "stock". Maybe @Jowett knows?

 

I doubt Toyota shares such info.

 

And dont you have a bunch of stuff done to yours?
Hell im on all box kit just boost referenced and snivs 76mm.
I mean I could be more around yours considering my boost gauge is weird.
I guess I could always get another one to test differences and return it when done lol

 

Although on stock pulley the gauge read I was hitting 6psi

 

Oh I forgot @helidave has the 76mm, so many truck configurations to keep track of. Might be time to make a spreadsheet so I look less dumb. In that case 5psi sounds right, and @NatesNightMare making 8+ sounds wrong. I would expect 8psi with the 70mm @ 7000ft.

 

You could buy a cheap mechanical boost guage (I used a $10 Amazon special) and have it set by the wiper blade. I did this once to verify my digital gauge was setup properly.

 

I'm on the 70mm though.

 

Yeah mines digital also and did their so called calibration for it but even at idle its not what everyome says it should be at as its at -6 lol

 

venmo me the cost of shipping and I'll send you my RTD and you can datalog all you want to send logs to sniv...

 

Wait, are you running the 1900 or the 2650? Maggy or harrop?

 

I've got an RTD already. Just need to get an Mpvi and better laptop

 

Ah ok - you can still log with the rtd though and send to sniv if inclined. A crap laptop with a battery lasting 20 min is all you need! (and the rtd of course)

 

I picked up a used laptop on Craigslist for $60, older Dell inspiron. I did a few upgrades and not worried if it gets dropped.

 

magnuson 2650 w/ 76mm pulley. Just went and did a few pulls and maxed out at 5.8psi boost.

 

I'll raise you one. I have an old surface pro 3 that you can have for free (well, the cost of shipping)

 

Haha. I was a bit skeptical as the ad went like this: selling my grandma's computer that she doesn't use anymore.

 

Yeah I think ill grab a cheap mechanical one off Amazon and test mine again

 

Shit, if thats the case I prob NEVER get into boost lol

 

Every once in awhile my ltft's would get out of wack. I thought it was from changing PE so much to get my water/methanol setup for 7psi -12psi activation.
Low and behold has history proves an air leak post MAF!
Yes @snivilous another air leak! This time right at my intake from the ccv system. A small crack that was just enough to mess my fueling up!

 

If your gauge shows -6"hg at idle, something is going on. For your elevation it should be around that with the engine off.

 

I've concluded a LOT of funky behavior is due to air leaks. If the narrowbands are doing any weird shit it's almost always that I think.

And there's a LOT of shit to check. The intake seems obvious, but don't forget the injectors are post MAF and that's 8 seals right there. There's multiple ports coming off the blower too. There was someone on here the other day where they found holes next to the wideband bung from the shop that welded the bung in, which seemed to be sucking air in and affecting the narrowbands.

Between that and all the issues we've seen with getting good fueling, there's a lot of stuff to go wrong. And of course all of that usually happens the same time the tune gets changed, further complicating troubleshooting where the issue exactly is.