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02EnvoySLT

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TxDoc Senior Enthusiast

TxDoc

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I am not an expert, and do not play one on TV.  I was poing around the LS1 site and ran across this:

 

Question 3-6: How does porting a stock MAF make more power?

 

Answer: In addition to the fact that the ported MAF allows for greater airflow, it also tricks the computer into thinking there is less load on the engine, therefore giving a few more degrees of spark advance. It also initially leans out the fuel mixture a lot, but the computer will relearn and richen it up again, although some have said that is still stays slightly leaner than before. As with all the mods that advance the timing, this mod is only recommended if you can get high octane gas. When I say high octane, I mean 93 or preferably 94 octane. It's wise to add some octane boost while drag racing as well (Super 104+ will raise the pump octane number by 2.2 when mixed as directed). In hot climates, this mod can result in detonation, especially when using 93 or less octane fuel.

 

I am not sure what a "ported" stock MAF sensor is, though. Thought I would post it and learn something.

02EnvoySLT Enthusiast

02EnvoySLT

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The LS1 have the 75mm MAF's which are metal and can be taken apart and ported (hollow out the metal ends).   Depending on the tune of the car and it's A/F ratio, it sometimes helps gain power and sometimes hurts power.

 

Most of the late model trucks have the 85mm MAF which is the same MAF that comes on the Corvette ZO6's and I believe 2001+ vettes.    The 85mm units can not be taken apart since they are press fitted and locked.    They can be ported but it takes quite a bit of time and know how.

 

I can't speak for the Granatelli truck stuff, but the LS1 stuff was/is a crap shoot.   They are "flow bench" calibrated by a company and no two seem to be a like in calibration.

 

I guess, it may work for you, or it may not.   Let us know how the truck versions work out if you try it out.

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