building an intake manifold, input needed

[sharkey]

http://www.trueleo.com/intake1.htm thats the trueleo intake, its a direct bolt on for rwd and fieros. it would bolt onto my motor, however i lack the hood clearance by 2-3". it has been proven on a flowbench to be a good improvment over stock. the downside is its $600, and apears to be made of steel.

im working as fast as i can to get it finnished. i will deffinitly let you guys know seat of the poants feel, however im unsure weather i will get it on the car before the last street legal race, wich is october 5th. im aiming for that, but i need it on for a week before hand so i can get the tuneing sorted out.

[2.8RS]

Finish it, i'd be interested to see if you got any more power. I basically have the same intake as you and would love to see anything out there that could improve flow.

[sharkey]

i had a guy in my car club attempt to make the lower flange. he managed to get the ports roughly cut out before he decided it was too much work. i finnished it off with a hack saw and file. i guess i could sit down on the drillpress and and drill a bunch of holes to cut the peice out, then finnish it with a file. time consuming, but could work.

[ForcedFirebird]

Let me know if you need the flanges made (I was planning on making them anyway for custom plenums), but I don't see why you couldn't make them the same way you did the MIM to LIM flange?

[sharkey]

well, after a night of work, i made a couple discoveries
1. im not able to make my own flanges for between the middle and upper intake. i realy need acess to a milling machine, and i dont have it. im real unsure on what im gonna do here
2. i screwed up, pretty bad. im using my holley fuel regulator with the knob missing off the top as a tester, however i discovered that the stock regulator, wich im running, is quite a bit taller. basicly, the fuel regulator is in the plenum. im not realy sure what im gonna do about this, with some complex work with the plenum i may be able to work around this problem, but it comes back down to being unable to cut the flanges out.

i have to do some more research now, but im back to considering dual plenum/throttle body setup. this way the fuel rail is wide open and im able to make this manifold one peice. this would solve a lot of issues im having.

[IsaacHayes]

Nice! Looks like you solved your intake problem! The 3400/etc LIM has rectangle/trapezoid ports too on the end. The 3500 style setup is known for power and you'll essentially have that with keeping your iron heads. You should feel a big boost since people that have felt increases from just going small port 3100 to large port, and then again others from large port to 3500 plenum. So from your small un-equal multiple bend stock intake this will rock! Can't wait to see the finished product!

Since it's custom you could even make it to work with whatever stock TB. So you could run bigger than 60mm if you wanted...

[ForcedFirebird]

speaking of 3500 plenums, does anyone have any dimensions for the 3500 plenum. im interested in calculating the plenum volume to use just as a refference. it

I tried quickly to get a rough volume on the 3500 plenum, and I kwept getting leaks at well over 3000cc's. Rough measurements are 10"x12"x2", but it has recesses on the bottom to fit a fuel rail. If I have more time before I start bolting everything up, then I'll try to get a more accurate measurement on the volume.

[sharkey]

its actualy a rectangular port in the head, but the flow is straight to the intake valve. thats part of the reason i built it like this, to maximize flow with no restrictions. the plenum will basicly be a big box, much like a 3500 plenum. depending on how tall i go, the plenum may end up around 190 CI, wich is a bit large for my liking. i can build it lower, however im concerned about port flow if i go any shorter.

speaking of 3500 plenums, does anyone have any dimensions for the 3500 plenum. im interested in calculating the plenum volume to use just as a refference. it

[IsaacHayes]

Cool. How does the lower look? Does it keep the flow straight from the middle part you just made into the heads? If so you'll end up with pretty much a 3x00 style lower with a 3500 style plenum..

[montess408]

lookin' good man !!!!

[Superdave]

nice work!

[2.8RS]

Looks pretty good. The plenum is a box type?

[sharkey]

as prommised




its still a bit rough. the runners end up being 15" total length, wich was what i was shooting for. if i wanted to go longer to try and hit the 2nd harmonic, i would have had to have some very tight bends to clear the hood, sacfrificing a lot of flow. i aimed for the 3rd and 4th harmonic, wich puts me right were i wanna be. now i know im gonna get comments on the shape of the top of the runners. basicly, i just pulledo ut the hammer and dolley and got them into a shape i throught would work with the top flanges. this shape also ended up with the runners being a bit of a velocity stack.

next thing is to get some aluminum and build flanges for the plenum. once i getthat done ill have the aluminum cut for the plenum (after i figure out the design), have brad weld it all up and itll be good to go.

[1988GTU]

Ok, like I said I was not sure. Now we know only Alloy design 2.8MPFI and 3.1MPFI LIM AND UIM can interchange (with slight mod) .

[sharkey]

you cant swap intakes cross generation, they are all different. if i had a viable intake option that would bolt on and fit the engine bay, i would (that leaves out the trueleo).