2-Piece Intake Flanges / Plenum

["Top Fuel" Bender]

To satisfy my stalker :p I've been asked about making a thick upper plenum flange for the 2-piece intake

I figured a 3/4" thick plate 4" wide 14" long
a FULL 1/2" radius (going to be an over lap in the center 2 holes)
3/8" deep blind holes (to keep from breaking thru the radius and prevent leaks) from the bottom
o-ring grooves around the ports to eliminate gaskets and prevent leaks
as always full deburred , top and bottom surfaced

ready for you to weld
Looking like $75 with a 10 person buy in
(radius cutter isn't going to be cheap, but the 3rd tool path will eat up alot of time)

If there's enough interest we could talk about a group buy on the plenum material, cut to length, pinned for alignment , opened on the bottom w/ a flange for welding or bolting to the flange
I could supply the end caps also (alot cheap then ross machine)

Basically a fully machined ready to weld kit
(To many variables and preferences on a finished plenum, plus everybody knows a welder around here)

[Ondonti]

Is there anyone offering lower flanges? Upper flange is a waste of time when you look at the runner diameters. Reverse taper is not a good thing. especially after people finish what they think = porting.

[Mopar318]

I would be interested in the ready to weld plenum kit with flanges. I do my own tig welding so that would be the way to go for me.:thumb:

["Top Fuel" Bender]

Is there anyone offering lower flanges? Upper flange is a waste of time when you look at the runner diameters. Reverse taper is not a good thing. especially after people finish what they think = porting.

Not that I've seen
We could could do it on the 4-axis or multiple setups
Probably in the $125-150 range though to make it like the factory with the injector bungs and a fuel rail mount

[johnl]

A phenolic heat isolator/spacer with O-ring grooves on both sides is another product idea

. . . . . . but I understand the silicon/glass dust is hard on both machines and lungs.


FWIW, you might double check hood clearance - 1/2" plate plus what ever increase in plenum diameter . . . . at least on an Omni, there's not much room to raise the top of the intake plenum; I crushed a ball of aluminum foil between the top of the 2 piece and the hood and I think I remember that I got about 3/4" clearance. When the engine torques, the plenum pulls down though.

[1984rampage]

Not that I've seen
We could could do it on the 4-axis or multiple setups
Probably in the $125-150 range though to make it like the factory with the injector bungs and a fuel rail mount

If I understand what you are talking about that would be pretty awesome for a custom intake! Your talking about making the flange and part of the runner where it attached to the head and including the injector bungs and fuel rail mounts correct?

[zin]

subscribed...:thumb:

Mike

["Top Fuel" Bender]

A phenolic heat isolator/spacer with O-ring grooves on both sides is another product idea

. . . . . . but I understand the silicon/glass dust is hard on both machines and lungs.


FWIW, you might double check hood clearance - 1/2" plate plus what ever increase in plenum diameter . . . . at least on an Omni, there's not much room to raise the top of the intake plenum; I crushed a ball of aluminum foil between the top of the 2 piece and the hood and I think I remember that I got about 3/4" clearance. When the engine torques, the plenum pulls down though.

it'll be close but it's going to be for everyone, I've seen a few cars with pig plenum intakes, shouldn't be an issue
A phenolic heat isolator/spacer plus even a 3/8" flange would take up more room

went with 3/4"
trying to get a nice gental radius into the ports
need the room for the radius without breaking into the bolt holes or getting too thin on the center 2 ports
thick piece that would give plenty of room for touching up should it warp


If I understand what you are talking about that would be pretty awesome for a custom intake! Your talking about making the flange and part of the runner where it attached to the head and including the injector bungs and fuel rail mounts correct?

That's the way I'd want it done
Just a real quick guess on the price
I could supply injector bungs separately and just the flange
but it'd be a pain to try and get all the runners uniform to get the injectors and rail to sit nicely

[Reaper1]

Just watching where this goes...

[GLHNSLHT2]

Is there anyone offering lower flanges? Upper flange is a waste of time when you look at the runner diameters. Reverse taper is not a good thing. especially after people finish what they think = porting.

Uhh when you add a plenum to the 2 piece and port it to the gasket you don't get a reverse taper. They go from big at the mating of the 2 pieces to smaller at the head.


A phenolic heat isolator/spacer with O-ring grooves on both sides is another product idea

. . . . . . but I understand the silicon/glass dust is hard on both machines and lungs.


FWIW, you might double check hood clearance - 1/2" plate plus what ever increase in plenum diameter . . . . at least on an Omni, there's not much room to raise the top of the intake plenum; I crushed a ball of aluminum foil between the top of the 2 piece and the hood and I think I remember that I got about 3/4" clearance. When the engine torques, the plenum pulls down though.


it'll be close but it's going to be for everyone, I've seen a few cars with pig plenum intakes, shouldn't be an issue
A phenolic heat isolator/spacer plus even a 3/8" flange would take up more room

went with 3/4"
trying to get a nice gental radius into the ports
need the room for the radius without breaking into the bolt holes or getting too thin on the center 2 ports
thick piece that would give plenty of room for touching up should it warp



I have a 1/2 thick or so phenolic spacer and a 4" tall plenum on my 2 piece. It sits lower than the stock plenum by far and it's even below the Valve cover level. How much farther you could go up I'm not sure.

[Juggy]

ive been thinkin about a plenum like i got from jay

but with a 52mm TB on each end of it :D

[Juggy]

Is there anyone offering lower flanges? Upper flange is a waste of time when you look at the runner diameters. Reverse taper is not a good thing. especially after people finish what they think = porting.

the diameter of the hole for the air entry of the lower 2 piece manny is much larger then the rest of the ports, especially after it makes the short turn into the straight away

the pic from the head side does not do the port any justice. but i can assure you everything tapers down towards the size of the head hole, even tho it looks kind of backwards (looks can be decieving...your eyes, dont trust them!)

[shelbyvnt2]

Bump! Anyone ever do any work on these flanges? I bought one from Lengel and it looked very good.