leaning a/f ratio with maf bypass screw?
 

ive used this kinda ghetto mod on 3 supras to up the fuel cut by 3-5 psi and it leans it out from like 13.2 to 13.8, 14.0 full (guesting on the numbers non of the supras have any way to check what the a/f ratio is) it works very well and i popped the plastic cover off on my maf (damn s5 maf are all plastic easy to get to the screw tho dont have to drill a metal plug like the supras) if any 1 is wondering what im talking about when a maf sensor is made at the factory there not all the same and so even if the electronic portion measures the same band a diffrenet amount of air may be flowing for each 1 made so theres a factory bypass screw so they all read the same per volume of air going through the maf

so my question is can i lean a 89 gxl na out this way and would it be safe on a rx7

also if any 1 reading this is wondering you could also close the screw further and richen the mixture (not recomened on turbo because will also make your fuel cut kick in sooner if you still have it, no fuel cut go right ahead and richen the mixture like this)

has no 1 tried this or does no 1 have any idea what im talking about?

when i have a chance ill take a pic of the screw im talking about and see if i can find my friends wide band and let you know how it effects the rx7 and ill call by boy with the supra and let you know how it effects that also (for the turbo non turbo comparison)

I'm no expert but this doesn't sound like a very good idea. Sounds like a good way to pop your motor. You should consider doing it right, i.e. get an s-afc and get it tuned professionally. Just my 2 cents..

Most people just get a SAFC and lean it out that way. If you don't have a wide band to measure your A/F Ratio, I would not recommend doing somthing liket this. There are by chance other more accurate ways then guessing.

yes i supose you could do this, but it would be a very crude method of leaning it out and i would not recomend it, as it may change your a/f across the whole rpm board and cause strange issues when cruizing around or idling.
So if u really want to try it,be sure u have some type of wideband a/f gauge to verify how lean your going.

thanks for the responses guys means a lot to me yea i know its not really a good idea but for some 1 broke (like me) and only getting 11 mpg it can be helpful but i wont mess with it till i can find my friends wide band it laying around his shop some where when i get the max readings for screw all in all out and in stock location ill let you guys know what happened

you can blow a rotary pretty easily by running it too lean.