I know this is an old post but I thought I'd post a comment to add to the discussion. About 30,000 miles ago I removed the butterfly shaft, butterflies and vacuum actuator and plugged the fore and aft holes with JB Weld.

The truck runs fine although I may have noticed a torque decrease just off idle. Not really sure though.

I would like to replace the system by purchasing a new plenum, but that will have to wait till I have the money, which may be never.

I would also like to experiement with it by temporarily sealing the butterfly valves closed with small aluminum plates and some tig spot welds to see what the performance and economy is like.

Right now I get about 15-18 around town with 33x12.5x15 BFG all terrains.

The only issue I ever had was trying to get smogged in CA. The tech gave me a fail-fix-and-return for having a golf tee in the vacuum line to the missing butterfly actuator. I told him it wasn't required, but he still failed me. I removed the tee and fed the line back into the small vacuum canister on the passenger side resevoir so it essentially looped back into itself. He passed me. What a load of crap.

Anyway, that's my story and I'm sticking to it!



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