Call this an exercise in teaching an old dog (read: the 3800, not me) new tricks.
We've been using the "LQ4" "85mm MAF" that was originally introduced on 1999 GM vehicles with our Northstar upgrade kits (and LS1 upgrade kits before that, that's how old it is) and in particular those who are going to buy them used at junk yards are often buying 10 year old sensors.
Since then, the LS7 card MAF (now used on LS3 and other) has become a popular upgrade on other applications and I decided to try it on the 3800.
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Benefits:
-Very new and accurate sensor, fast updating
-You can buy aftermarket MAF housings in full 4" (100mm) size for great flow
-Not that expensive to set up with all new parts
For the test, the parts involved were a polished aluminum 4" MAF housing, a low restriction honeycomb screen, an OE manufacturer brand MAF that was confirmed "strong" (google "strong ls3 maf" for more info), and a wiring harness adapter for this specific sensor swap.
Here's an installed photo from a very nice 2004 Monte Carlo SS. Owner had installed one of those JMB intakes which is a full 4" piping, along with a Northstar throttle body upgrade. Rather than necking down with the 85mm truck maf that normally comes with the Northstar kit, the setup retains 4" straight through.
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Once I'd developed the MAF calibration curve, my observations were:
-a nice crisp throttle response, which isn't always achieved with a large MAF housing
-MAF frequency at WOT reduced by roughly 2000 hertz, meaning that although it's easy to max out the frequency even on the 85mm truck MAF, this MAF will provide lots of headroom and support any supercharged setup
Only issue so far is the IAT sensor built into the MAF is calibrated different, and I'm still trying to source the coding inside the PCM to recalibrate it. The fix for now is simply reuse the factory IAT sensor as we did here.
Turbo guys: Instead of using the even older metal "LT1" MAF, which is now 20 years old (!!), this could be the ideal MAF setup. This card MAF should provide lots of headroom in frequency, and combined with a housing with a low restriction honeycomb screen it should flow better than the LT1 MAF. While the housing I used on the supercharged setup was a thin aluminum housing, I've sourced a much sturdier housing for turbo use.
I may make up kits if there's interest, for those who want to ensure they get the right mix of parts to set it up. For now, I'll simply say yes the LS7 MAF works well on a 3800, its nice to use such a new and up to date sensor, this is something I recommend and yes this does mean I can now tune for it *thumbs up*