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I'm more looking at just the space available for the stack... And bending stack would require completely reworking the intake tube later.

The entire GM tuning industry is built around MAFs, so I'm not going to buck that trend!

Problem is just the same-old... making everything fit. Like Gordon Murray said, the automotive problem is one of packaging.

I'm hearing a lot of what won't work, at some point sooner rather than later, you need to accept perfection doesn't exist and put a throttle on that thing.

I'm going to get a " MAFs suck" shirt made and sent it to you. That is an emissions part and has no place on a performance engine.....and I thought the GM ECUs could be setup and tuned with MAP?...might be wrong but I thought it was baked in as a failsafe and could be used? Either way, get on with it already man and put a throttle on it!

Hey, pistons suck, apex seals blow! MAFs are just in the middle

MAF based load calc actually makes the engine really easy to tune, as you're just dealing with a 2d MAF table (mass flow vs output frequency) vice a 3d table (VE vs. MAP vs. RPM) and civilizes big cam engines pretty well. Many tuners disable MAP and go MAF only. Tuning both so they back each other up is actually a more expensive luxury.

So....not so much. You are right that many tuners use only MAF because they can tune it quickly and make more money, but that is not a reason to follow that path.

Big cams are a problem for MAF and a big reason people switch to MAP. Overlap causes reversion, and reversion means the air is counted more than once by the MAF and the mixture is bugged. The OEM spend a lot of time on cam, intake, and inlet tube design to get the MAF to work correctly. At the extreme end is CIS systems.....they tolerate 0 reversion but the moire points you add to tables the more reversion can be mapped and accounted for but it would never work right on an engine like mine and my cams aren't that radical overlap wise but do create a lot of noise in the intake at certain RPMs.

Another reason they are removed from performance engines is that another name for them is flow restrictor. If the MAF is small enough to give good readings at idle then its going to restrict flow on top. Not a big deal on boosted engines but a problem for NA setups, 5%+ hp loss is typical.

But, like the matrix, no one can be told about MAF issues, you need to experience it for yourself. Issue 1 is getting enough space to install the damn thing

I haven't heard of LS tunes having to deal much with reversion. Maybe it's the manifold spreading reversion from the cylinder at IVC to the next cylinder in the firing order, combined with plenum volume smoothing the reversion signal before it gets back to the MAF, maybe double-checking via MAP differentiates it or the factory ECMs are smart enough to figure it out.

Anyway, it's very common and I haven't heard of problems. I'll let you know how it works out. I'll be taking it to a reputable tuner in VA.

Very honestly, I've never seen anyone with big cams and an MAF as the 2 are best for different applications (hp vs easy tuning)....how much cam do you have?

.....and its not going to any tuner without a throttle

....just like mine's not going anywhere with leaking head gaskets

For now I have the stock high performance 266I/244E cams.
I have an upgrade path planned to install extra 266 intake cams in the exhaust locations.
I also have a set of 288 regrinds and a pair of redrilled intake sprockets to advance intake cams 10 degrees on the shelf to play with after the 266E upgrade.

Those are durations at 0.1mm lift, IIRC. Yeah, I remember yours are in the range of 235 degrees at 0.050" lift.

With factory cams MAF is no issue, they sorted it for you so carry on.

Yes, I have more duration, @.006" at the valve I have 274/285....0,1mm is like ,004 so maybe 279/290 at the valve? and maybe another 5-10 degrees at the lobe as lash is about .010". For comparison my .050 numbers are 242/247 lobe, 240/245 valve....which are still relatively mild numbers. The ramps are steep to get the lowest seat to seat I could with decent .050 numbers to try to keep a decent low-end and port flows are high so more .050 duration doesn't add much until the engine is over 10k.....seat to seat number are mostly telling about idle and and low end, .050 is a good way to compare how different grinds impact top end.

Why are you talking about bigger exhaust cams? I was unable to get my exhaust flow as high as I wanted it and had to compensate with a bigger cam. If the factory used a much smaller exhaust cam that usually indicated the opposite problem but I know little of northstar engines....I did read the aroura indy engines needed 20 degress less exhaust than intake to work right but no idea if that in anyway applies.

I haven't seen any real dyno evaluations of different cams in NorthStars... Keeping in mind that it's a Cadillac, the reduced exhaust duration may have been to keep the exhaust quieter? OEMs have requirements other than just power and torque, as weird as that may seem to us.

Do you have flow numbers or can you hunt them up? if so we could get it into Dynomation and see what you're cam option might do father than guessing. Just looking at flow numbers alone can also be very helpful, the %exhaust it to the intake flow kind of tells to the relative durations to use on each....but DM give much better answers.