scratch built "box" plenum
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From: Mid Michigan
Car: 89 iroc convertible
Engine: 305 tpi
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scratch built "box" plenum
Okay guys tell me what ya think. I am building a 383 with vortec's. I was thinking of perhaps trying to fab my own plenum. My profession grants me lots of equipment to build things. I figured I could construct the "box" from delrin ( high grade nylon type stuff ) or aluminum. I could mod the runners by milling almost in half and welding on flanges. Has anyone on here ever tried it? What do ya think of this? I am thinking it would run just fine as long as I keep the runner length the same on all eight. Just think a delrin plenum!
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I had considered something similiar to what you're proposing, except that I was going to mill down some SLP runners and fab my own SuperRam style plenum. I ended up not doing it since I don't have access to a TIG welder, and while I've MIG welded alumimum it's probably not the way to go here.
If you could fab a SuperRam-kind of plenum, and avoid the headaches that exist with that SuperRam, you might be on to something. I don't know how Delrin looks, but the look of polished aluminum is hard to beat.
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Re: scratch built "box" plenum
Originally posted by mavis_1
Okay guys tell me what ya think. I am building a 383 with vortec's. I was thinking of perhaps trying to fab my own plenum. My profession grants me lots of equipment to build things. I figured I could construct the "box" from delrin ( high grade nylon type stuff ) or aluminum. I could mod the runners by milling almost in half and welding on flanges. Has anyone on here ever tried it? What do ya think of this? I am thinking it would run just fine as long as I keep the runner length the same on all eight. Just think a delrin plenum!
Okay guys tell me what ya think. I am building a 383 with vortec's. I was thinking of perhaps trying to fab my own plenum. My profession grants me lots of equipment to build things. I figured I could construct the "box" from delrin ( high grade nylon type stuff ) or aluminum. I could mod the runners by milling almost in half and welding on flanges. Has anyone on here ever tried it? What do ya think of this? I am thinking it would run just fine as long as I keep the runner length the same on all eight. Just think a delrin plenum!
yup.
athough if i had access to the equipment, i wouldnt be keeping the stock base
id probly machine a single plane carbed intake to hold the stock injectors/fuel rail, and then make a box plenum to go on top... and mount the throttle body to it in roughly the same place as stock..
athough there is a guy on here from sweden that beat me to it.
I thought about modding my plenum, and the runners too. I even bought a whole TPI setup as a back up, so I could experiment. I was planning to widen the stock plenum and shorten the runners accordingly. I even thought about totally siamesing the runners with sheet alum. I do have a tig by the way. Then I realized why do all this work, when I can start with a known good intake ( I have a Victor Jr) and just adapt it to EFI. Believe me, I was on you track but then I saw the light. The only benefit to modding the stocker is to be able to say its still a TPI. The single plain way is much simpler.
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