Maf For Boosted Project

JD1964

there is enough sticking out to grab on to
15 Year Member
Jun 28, 2013
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My sig has my setup.

I'm gonna add a Vortech V3 Sci (5-6psi). Got the SVO 30lb injectors already.

My question is regarding MAF for this application.

Can I use my current MAF (70mm from 94 Marquis) if I get a chip and have it tuned by a pro with dyno to match the 30lb inj? So far, two pros I've talked to question whether the current Marquis MAF will have enough electronic curve to cover the increased air ingestion. But I swear somewhere on here someone said my current MAF will work if properly tuned with chip in ECU.

Just looking for confirmation.

I realize these tuners are used to doing what they normally do. I feel like I'm asking them to step slightly outside of their comfort zone. One says I need to buy and aftermarket MAF, the other says maybe I don't and is willing to try.

Which way do I go?
 
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That maf will be pegged... If you are going to go to a tuner buy a slot style maf and put it in a 3" tube. Like an hpx slot maf. If not, buy a matched maf for your injectors.. I don't know if the 30lb injectors will be enough either..
 
That maf will be pegged... If you are going to go to a tuner buy a slot style maf and put it in a 3" tube. Like an hpx slot maf. If not, buy a matched maf for your injectors.. I don't know if the 30lb injectors will be enough either..

I got a Kirban adjustable regulator already. I can crank it up if needed. Considering that, you think 30's are not enough?
 
I got a Kirban adjustable regulator already. I can crank it up if needed. Considering that, you think 30's are not enough?
Yes that should be enough if you adjust pressure or use a fmu. I personally would get big enough injectors and get rid of variables like messing with pressure, and just let the professionals take care of the adjustment in the tune. I know my 94-95 70 mm maf was just about pegged with a gt40 setup, so I would buy a new maf at least.
 
Nearly every centrifugal supercharger setup will run a draw-thru MAF, simply because it's easier to do so. A blow-thru MAF would require a custom or modified discharge pipe. On the opposite side of the coin, it's better for turbo guys to run blow-thru because of all the intercooler piping. A draw-thru meter would put the meter quite a distance from the engine and could cause a noticeable delay in what the meter reads and what the engine sees. The turbo could also create backwash through the meter on a draw-thru setup, and that's something that cannot be tuned around. You don't usually have those concerns with a blower setup.
 
Nearly every centrifugal supercharger setup will run a draw-thru MAF, simply because it's easier to do so. A blow-thru MAF would require a custom or modified discharge pipe. On the opposite side of the coin, it's better for turbo guys to run blow-thru because of all the intercooler piping. A draw-thru meter would put the meter quite a distance from the engine and could cause a noticeable delay in what the meter reads and what the engine sees. The turbo could also create backwash through the meter on a draw-thru setup, and that's something that cannot be tuned around. You don't usually have those concerns with a blower setup.
Ok, that explains it. Thanks for the clarification, made perfect sense.
 
I have an AFPR that has been sitting, brand new, in a cabinet in my garage for probably 6 or 7 years now.

With a proper tune and sufficient injectors, stock fuel pressure is just fine for most typical builds at sane power levels.

Google "fuel injector calculator" and plug and chug your expected power levels to determine if the 30s will be enough.
 
30's will support up to 400rwhp by itself (without) an FMU. "At least they did for me on my SSC". I ran a simple 73mm C&L meter calibrated to the 30's and it ran great!
Once I upgraded beyond 400rwhp I went to 42's and 80mm ProM meter.

You can glance at my combo in Sig below to get an idea of what I've got going on with my vert.

No matter what you do, IMO you will need to seek a dyno and get the new supercharged combo tuned.
 
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