What is the difference in the block between Active Fuel Management and non?
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What is the difference in the block between Active Fuel Management and non? ***NOTE: I'm reposting this because I think my previous title (which was supposed to be what you see on this post) has kept people away from my previous post. The previous title ended up being "What is". VERY sorry for the spam. I'll also post the replies to the old post.***
Just like the title says. I know that AFM has a different lifter valley cover with hydraulic actuators and passages, and I know it uses collapsible lifters to shut off those cylinders, but what are the differences in the block? Also, do non AFM gen IV blocks have the provisions for AFM?
A little backstory: I have a brilliant beyond expensive idea
I've had a '89 Firebird (V-6... weak sauce..), my Grandpa (may he rest in peace) bought an '87 T/A new, and my whole family has been Pontiac people for decades. I want a third-gen T/A. But I don't want no run-of-the-mill 305 or 350 powering it. That's not very 'me'. No, I want a 5.3 (or BETTER! though I'm kinda partial to the 325.1 C.I., because then I can get 326 badges for it!). But even just a garden-variety 5.3 is not quite awesome enough... No, I wanna see what one of these highly aerodynamic cars can do for MPG when it's only got 4 cylinders running it on the highway!
Just like the title says. I know that AFM has a different lifter valley cover with hydraulic actuators and passages, and I know it uses collapsible lifters to shut off those cylinders, but what are the differences in the block? Also, do non AFM gen IV blocks have the provisions for AFM?
A little backstory: I have a brilliant beyond expensive idea
I've had a '89 Firebird (V-6... weak sauce..), my Grandpa (may he rest in peace) bought an '87 T/A new, and my whole family has been Pontiac people for decades. I want a third-gen T/A. But I don't want no run-of-the-mill 305 or 350 powering it. That's not very 'me'. No, I want a 5.3 (or BETTER! though I'm kinda partial to the 325.1 C.I., because then I can get 326 badges for it!). But even just a garden-variety 5.3 is not quite awesome enough... No, I wanna see what one of these highly aerodynamic cars can do for MPG when it's only got 4 cylinders running it on the highway!
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Originally posted by S10xGN:
"AFAIK, the only difference in the block is the (DOD) towers. AFM blocks are drilled and non-AFM blocks are not. You'll see either oil holes or solid towers after removing the valley cover..."
"AFAIK, the only difference in the block is the (DOD) towers. AFM blocks are drilled and non-AFM blocks are not. You'll see either oil holes or solid towers after removing the valley cover..."
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So then, could a talented machinist drill the needed passages into them? How difficult would that be? Obviously I'm not doing it in my garage with a gun, but my dad is a machinist, possibly with access to a precision machine that could do the work.
Andrew
