Hey guys,

I'm going to be redoing my Fiero in a year or so. I have some other projects to finish up. But I'd like to try to improve the stock intake some. Right now, I have a 3.2 V6 hooked up to an automatic. My 5-Speed Fiero is really a parts car and I bought it to swap out the Getrag into my auto Fiero. So, I have a spare 87 Intake and I'd like to try to improve the air flow. I know that the trueleo intake is really the way to go, but I'm really anal about the way things look. If it's not stock looking, then I just don't like it.

On my 3.2 I currently have the Darrel Morse bored throttle body and matched to the intake. The intake runners and the lower intake manifold have also been matched (did it with an air tool).

I'd like to know where the biggest restriction in this intake is. Is it the size of the runners? Or is it in the plenum?

I'd really like to try to improve the overall air flow so that I can get power above 4,000 rpms. It wasn't as obvious to me when the motor was stock, but with the increased displcement of the 3.1 crank and rods and .040 overbore pistons, it really really makes it obvious now. I mean, above 4,000 rpms, it's like the motor pretty much falls flat on it's face.

Has anyone cut open the complete intake tract to see exactly where the biggest restrictions are? If I was to get real happy with a grinding tool, where would I need to grind to see the biggest improvement?

Thanks!!!

------------------
Todd,
2006 Pontiac Solstice
2004 Volkswagen Beetle Convertible (Wife's Car)
2002 Ford Crown Victoria LX
1997 Pontiac Grand Am GT
1987 Pontiac Fiero SE / V6 5-Speed
1987 Pontiac Fiero SE / V6 (3.2L) Auto
1984 Pontiac Fiero 2m4 SE
1981 Pontiac TransAm (Olds 455BB)
1973 Volkswagen Type-2 Transporter

There is tons of discussion on this thread - https://www.fiero.nl/forum/Forum2/HTML/051176.html

If you run a search on "intake" you will see alot of different approaches and some good tips.

Arn

You might want to look at the PPG pace cars. The intake looks stock, but if you look closely, the intake is highly modified. I have been told, that the car was revved to 6000 RPM's and the car was still pulling at 130 MPH and the one with the turbo ran at 165 MPH. Now, of coarse, there is other mods done to the engines in these cars. Here is a thread on the cars. https://www.fiero.nl/forum/Forum1/HTML/050854.html
You might ask, what else was done to these engines, to perform like they do.

------------------
WWW.CLEVELANDFIEROS.COM

https://www.fiero.nl/forum/Forum1/HTML/052322.html#lastpost
My rear defuser

After cutting one open,
this is the worst restriction (57mm TB gasket0:

I have a trueleo intake on my 3.2 and it pulls hard to 6000 rpm. Might just want to save up and get it.

------------------
Low 14 sec 99 Pontiac GTP, 3.2L V6 4 sp 86 Fiero GT

Man, this sucks.

I am REALLY anal about how my cars look. They HAVE to look 100% stock. I absolutely hate the aftermarket look of most products. Things have to be very OEM looking to me otherwise I don't like them.

Maybe there's some way that I can increase the size of the plenum? Perhaps if I cut one in half at the seam, and then I cut another one at the top and bottom, I could fit the middle piece in between the top two pieces, then weld them, and grind down the weld marks and it would look almost totally stock?

------------------
Todd,
2006 Pontiac Solstice
2004 Volkswagen Beetle Convertible (Wife's Car)
2002 Ford Crown Victoria LX
1997 Pontiac Grand Am GT
1987 Pontiac Fiero SE / V6 5-Speed
1987 Pontiac Fiero SE / V6 (3.2L) Auto
1984 Pontiac Fiero 2m4 SE
1981 Pontiac TransAm (Olds 455BB)
1973 Volkswagen Type-2 Transporter

Todd, To begin with check out these threads on the Fiero intake. https://www.fiero.nl/forum/Forum2/HTML/067399.html and https://www.fiero.nl/forum/Archives/Archive-000001/HTML/200501...
Several people have tried to make the Fiero intake perform better. For the most part each attempt has focused on a certain area of the intake. The Truleo intake has pretty much eleminated the lower intake as being a part of the problem. That leaves us with the upper and middle sections. I have cut the bottom out of an early intake, and observed these restrictions. The opening behind the throttle body actually gets smaller right after the machined area. Next the EGR boss and hole disrupts air flow. Next the neck bends and flattens to about 2/3 the size of the throttle body flange. Then finally the area where the plenum bolts to the middle is a constricted sharp turn. Finally the middle intake where it mates to the lower is a terrible mismatch. Now that we have identified the restriction locations we need some critical information to decide how best to accomplish our goal. What should be the diameter and length of the intake runners. John Stricker calculated that the runners should be shortened 60mm. His expieriment flowed more air, and moved the power band to the right about 400rpm. Travis (1fst2m6) increased power on hid 2.8 by shaving .4" off the top and bottom of the middle intake, and .4" off the flange of the plenum.
It must be remembered that the intake is just one part of a system. It must be tuned to the rest of the engine. Displacement,compression, cam profile, valve diameter, head porting, and exhaust flow all play a part in ther final outcome.

Chuck

quote Originally posted by fierochild: Todd, To begin with check out these threads on the Fiero intake. https://www.fiero.nl/forum/Forum2/HTML/067399.html and https://www.fiero.nl/forum/Archives/Archive-000001/HTML/200501... Several people have tried to make the Fiero intake perform better. For the most part each attempt has focused on a certain area of the intake. The Truleo intake has pretty much eleminated the lower intake as being a part of the problem. That leaves us with the upper and middle sections. I have cut the bottom out of an early intake, and observed these restrictions. The opening behind the throttle body actually gets smaller right after the machined area. Next the EGR boss and hole disrupts air flow. Next the neck bends and flattens to about 2/3 the size of the throttle body flange. Then finally the area where the plenum bolts to the middle is a constricted sharp turn. Finally the middle intake where it mates to the lower is a terrible mismatch. Now that we have identified the restriction locations we need some critical information to decide how best to accomplish our goal. What should be the diameter and length of the intake runners. John Stricker calculated that the runners should be shortened 60mm. His expieriment flowed more air, and moved the power band to the right about 400rpm. Travis (1fst2m6) increased power on hid 2.8 by shaving .4" off the top and bottom of the middle intake, and .4" off the flange of the plenum. It must be remembered that the intake is just one part of a system. It must be tuned to the rest of the engine. Displacement,compression, cam profile, valve diameter, head porting, and exhaust flow all play a part in ther final outcome. Chuck

I would go this route, with what he said and what you find in those threads. You should be able to cut open your stock upper intake and modify the areas needed like triker and jstricker did with out making it too obvious. trikers, for example, will be hidden when installed. strickers is a bit more obvious, but it doesn't look much different than the later model 2.8s with the flat plenum. Once you have it opened up, you can get inside with a dremel and port out the runners a bit and polish them. The middle and lower intakes you can do to match much easier than the upper. The biggest problems are the TB neck, low upper plenum volume, too long runners, and runner size. All of that can be taken care of if you combine trikers and jstrickers work and port the middle and lower manifolds to match. It will look pretty close to stock in the end.

what about just having it extrude honed? i would like to see the improvements that would yield.

I just recieved information on the Truleo that could change many assumptions about the stock intake modification. The short Truleo is 14" long and 1 5/8" od. Assuming a 1/16 wall thickness that would yield a diameter id 1 1/2". The area of the intake runners would be 1.766" The stock Fiero intake has a length of 11" with an area of 1.59" The stock intake is shorter and smaller than the Truleo. This thing has just exceeded my pea brain. Can an 11" intake be made to perform like a 14" intake. Will enlarging the diameter of the runners allow sufficient cfm without killing velocity? I think it's time to find an automotive engineer for a little friendly advice.

Chuck

Well, the cross sectional area will determine flow capacity and velocity.
The runner length has the most affect on the torque curve and where the torque peak is.
That sounds like the Truleo would be better for lower rpm torque, even if it has the capacity to flow more at higher rpms.
If you can get the cross sectional area of the factory runners higher, then with their shorter runner length you should have a better high rpm intake than the Truleo. (all speculation, though)

I would love to see just how far the OEM intake can be taken, while still looking like the OEM intake.

Many have tried but none have come up with any significant improvements. All I can say is if your expermient requires more than $500-600 then might as well get the trueleo.

quote Originally posted by goatnipples2002: Many have tried but none have come up with any significant improvements. All I can say is if your expermient requires more than $500-600 then might as well get the trueleo.

Well, I'll be honest. My 81 TransAm with the Oldsmobile 455 Big Block will take me as quick to 60 as I could ever possibly want.

All that I'm trying to do is get the ABSOLUTE MOST power I can out of my original rebuilt engine block (3.2), and improve the entire car's performance, while keeping it 100% stock looking.

I went so far as to spray paint the Accel Ignition coil with black engine enamel because I want it all to look totally stock. Everything down to the spark plug wires, the red distributor cap, all the correct plug-wire loom brackets, etc. I want the car to look 100% stock. A Trueleo.. although an excellent piece, is completely about as far from stock as I would want. If I went with the trueleo, then I would probably just swap a 4.9 into there.

I have a couple of spare intakes... I think I may cut one out and measure. the thickness. I'm probably going to buy a cheap caliper and grind away as much as I can without affecting it's structure.

Thanks,

------------------
Todd,
2006 Pontiac Solstice
2004 Volkswagen Beetle Convertible (Wife's Car)
2002 Ford Crown Victoria LX
1997 Pontiac Grand Am GT
1987 Pontiac Fiero SE / V6 5-Speed
1987 Pontiac Fiero SE / V6 (3.2L) Auto
1984 Pontiac Fiero 2m4 SE
1981 Pontiac TransAm (Olds 455BB)
1973 Volkswagen Type-2 Transporter

quote Originally posted by 3.8 SC: You might want to look at the PPG pace cars. The intake looks stock, but if you look closely, the intake is highly modified. I have been told, that the car was revved to 6000 RPM's and the car was still pulling at 130 MPH and the one with the turbo ran at 165 MPH. Now, of coarse, there is other mods done to the engines in these cars. Here is a thread on the cars. https://www.fiero.nl/forum/Forum1/HTML/050854.html You might ask, what else was done to these engines, to perform like they do.

this is my pic i took of the yellow car at dells this past summer
and as you can see.. the intake is not milled out inbetween the runners but from what i remember i am reasonably sure that this is just a cosmetic thing, and not connected on the inside so nothing other than looks but i have been known to be wrong before, but i think i touched it and it was thin like just casting from the mold that was never removed
BUT when you look at the side angle it looks to be a little thicher than a stock one

[This message has been edited by $Rich$ (edited 01-01-2006).]

I can understand wanting the stock look and our intake is anything but that! Lot's of folks like the race car look and are more into function and HP than form which is why we sell them. A little advise about modifing the stock unit as we also tried to go that way at first; open the neck up as much as you can without weakening it and don't kill yourself with trying to enlarge the runners because they are not the only fault left in need of correction. That sharp turn the air must take betqween the upper and middle sections is a real velocity killer. BTW: spacers between the upper and center units won't help much unless you also weld-in lots and lots filler and then grind it all into a smooth curve. Even then, you still end up with to tight a turn. So open up the neck or save yourself the work and get a bored DM intake and one of his TBs.

quote Originally posted by Francis T: I can understand wanting the stock look and our intake is anything but that! Lot's of folks like the race car look and are more into function and HP than form which is why we sell them. A little advise about modifing the stock unit as we also tried to go that way at first; open the neck up as much as you can without weakening it and don't kill yourself with trying to enlarge the runners because they are not the only fault left in need of correction. That sharp turn the air must take betqween the upper and middle sections is a real velocity killer. BTW: spacers between the upper and center units won't help much unless you also weld-in lots and lots filler and then grind it all into a smooth curve. Even then, you still end up with to tight a turn. So open up the neck or save yourself the work and get a bored DM intake and one of his TBs.

Thanks Frances, I assume you are one of the guys who created the Trueleo intake?

I'd LOVE to have that intake, but it just doesn't fit my ultimate goal for this car.

I do actually already have the Darrel Morse bored out throttle body, with the matched intake plenum. That is the intake I would ultimately be modifying. I figured I would try to improve, even more so, the volume of the inside of that plenum.

I'm going to use a caliper and measure the area all over as I grind. I hope to at least improve it somewhat, and create a mirror finish inside.

Thanks!

------------------
Todd,
2006 Pontiac Solstice
2004 Volkswagen Beetle Convertible (Wife's Car)
2002 Ford Crown Victoria LX
1997 Pontiac Grand Am GT
1987 Pontiac Fiero SE / V6 5-Speed
1987 Pontiac Fiero SE / V6 (3.2L) Auto
1984 Pontiac Fiero 2m4 SE
1981 Pontiac TransAm (Olds 455BB)
1973 Volkswagen Type-2 Transporter

Can anyone post or resize a picture for me. I have a photo of my "in process" plenum modifications I would like to post. It is a 425k file and the software that came with the camera doesn't allow resizing.
I have opened up the bottom of the plenum, and neck. I have shortened the runners, and opened the runner access into the area that attaches to the middle intake. I will be welding a piece of 1/8" thick sheet aluminum to the runner flanges, bottom of the plenum, and close in the space between the fingers. I will then fit and weld a piece of approiately sized pipe to the underside of the neck, and blend it into the floor of the plenum. Similer to what Triker did. Only I will delete the egr flange.

Chuck

quote Originally posted by fierochild: Can anyone post or resize a picture for me. I have a photo of my "in process" plenum modifications I would like to post. It is a 425k file and the software that came with the camera doesn't allow resizing. I have opened up the bottom of the plenum, and neck. I have shortened the runners, and opened the runner access into the area that attaches to the middle intake. I will be welding a piece of 1/8" thick sheet aluminum to the runner flanges, bottom of the plenum, and close in the space between the fingers. I will then fit and weld a piece of approiately sized pipe to the underside of the neck, and blend it into the floor of the plenum. Similer to what Triker did. Only I will delete the egr flange. Chuck

Hi, I can resize for you, and also host it.

send it to me in an e-mail..

toddjasp@bellsouth.net

------------------
Todd,
2006 Pontiac Solstice
2004 Volkswagen Beetle Convertible (Wife's Car)
2002 Ford Crown Victoria LX
1987 Pontiac Fiero SE / V6 5-Speed
1987 Pontiac Fiero SE / V6 (3.2L) Auto
1984 Pontiac Fiero 2m4 SE
1981 Pontiac TransAm (Olds 455BB)
1973 Volkswagen Type-2 Transporter

Heres one from westcoastfiero.com : http://www.westcoastfiero.com/intake/intake_manifold_60.html

quote Originally posted by Francis T: So open up the neck or save yourself the work and get a bored DM intake and one of his TBs.

Hi Francis,

Do you think the 57mm TB and matched upper plenum (by D.M) will be enough or is it a must to open up the neck like triker
has done.

O.K and now to business

What is the estimated improvement (bang for $$) with these options:

1. 57mm T.B & matched Upper Plenum
2. Open Neck + 57mm T.B & matched Upper Plenum
3. Best Trueleo intake

Thanks.

[This message has been edited by Mister (edited 01-02-2006).]

It all depends on what kind of power you are lookiong for. Hp equals cfm air flow. Air flow is effected by the entire air tract of the engine. A stock 2.8 or 3.4 engine normally asperated would have a VE (volumetric efficiency) of approximately 83% The same engine with a good intake, ported & polished heads, SS valves with good valve grind, high lift cam, roller rockers and custom high flow tuned eshaust system would be in the low 90s VE. You MUST think of the engine as a system. The intake is just the first part.
Go to: hhtp://www.csgnetwork.com/cfmcalc.html
Plug in the numbers and see what it takes to make power. Examples: a stock 2.8 would have a VE of approximately 83%. At 6200 rpm it would need to flow 255cfm of air. A completely built 2.8 would need 276 to 295 cfm at 6200 rpm. (depending on the extent of the build) A 3.4 would need 334 to 354 cfm of air. The stock intake is rated at 318cfm at 100% A figure witch is impossible in the real world. At 90% efficiency the intake will only yield 286 cfm. So you can see that the stock intake would have difficulty suppling enough air for a fully built 2.8. A Darrell Morse intake and throttle body will get you approximately 50 additional cfm of air. Enough for a built 2.8, but far short for a built 3.4.
The Truleo is by far the simplest answer for making power with a 3.4 engine. I like others however, want to keep my engine looking stock to the casual observer. For this reason we are expierimenting with the stock intake attempting to get it to flow sufficient air on a 3.4.

Chuck

[This message has been edited by fierochild (edited 01-02-2006).]

Thanks for the detailed reply fierochild, We are all in the same boat (anchor) ...

To put it simply; if you have a 57mm TB, you need at least a 57mm neck. Since the neck is not round inside, you'll have to do the math. Measure the area where it is the smallest, if it's smaller than 57mm, the extra TB area is wasted. A side note, one thing that some folks seem overlook, our intake is a bolt-on! You can take it off if you want to sell the car to someone that wants the stock look. Anyone that has driven a Fiero with our intake, upon driving their car again instantly hates the stock intake no matter what it looks like.

the only problem... i hear in calif they are going to do road side visual inspections
for emissions (damn govermnet smog wackos)
pop the deck and see yours busted !!!!!! (and from info i got , if its modified and
not on their list of approved goodies you have to have it towed,cant be legaly driven
because its not smog/emission approved .(damn smog nazi )
a mod stock where they cant reely see it might squek through
just a thought

dont you got to love calif

------------------------------------------------------------
I havent lost my mind....
i just misplaced it !!!!!

[This message has been edited by metoady (edited 01-02-2006).]

quote Originally posted by metoady: the only problem... i hear in calif they are going to do road side visual inspections for emissions (damn govermnet smog wackos) pop the deck and see yours busted !!!!!! (and from info i got , if its modified and not on their list of approved goodies you have to have it towed,cant be legaly driven because its not smog/emission approved .(damn smog nazi ) a mod stock where they cant reely see it might squek through just a thought dont you got to love calif

Where did you hear that? I sure haven't. I don't think they have the time or money to do that, not with the budget with the way it is. Plus, hows some roadside inspector going to know what a stock Fiero engine is supposed to look like? Now when you go in for smog in 2 years, then you might have a problem.

they have a couple of sticks inthe fire
the reason they are going to do this is to raise money
they also are talking about removing all exemptions
and killing off the 25 yr law
they are also talking about going yearly
that sucks........
i know people at bar
they have been using remote sensing equiptment for 6 month
it takes reading via inferred and makes a note ot licence plates

i think big brother is going is having way to much fun

They're always talking about a lot of stuff, but we'll see what actually goes through. Sucks this state is under the thumb of the Sierra Club and Green Peace. I'm all for saving the environment, but those people just hate cars period and want to screw the rest of us over to get what they want.

quote Originally posted by Fastback 86: They're always talking about a lot of stuff, but we'll see what actually goes through. Sucks this state is under the thumb of the Sierra Club and Green Peace. I'm all for saving the environment, but those people just hate cars period and want to screw the rest of us over to get what they want.

California is under the impression that old cars are hurting the air quality. They are convinced that by eliminating all older cars, they can drastically improve the air. What they don't consider is that the number of old cars in California make up less than 5% of the total vehicles used. In addition to this, those older cars are often weekend vehicles and are not daily drivers for the vast majority of their owners. That means that they make up less than 1%.

They don't really consider this... the state of California has almost become a home owners association.

I'm glad that Florida is on the "right" side of the country. : )

------------------
Todd,
2006 Pontiac Solstice
2004 Volkswagen Beetle Convertible (Wife's Car)
2002 Ford Crown Victoria LX
1987 Pontiac Fiero SE / V6 5-Speed
1987 Pontiac Fiero SE / V6 (3.2L) Auto
1984 Pontiac Fiero 2m4 SE
1981 Pontiac TransAm (Olds 455BB)
1973 Volkswagen Type-2 Transporter

quote Originally posted by 82-T/A [At Work]: California is under the impression that old cars are hurting the air quality. They are convinced that by eliminating all older cars, they can drastically improve the air. What they don't consider is that the number of old cars in California make up less than 5% of the total vehicles used. In addition to this, those older cars are often weekend vehicles and are not daily drivers for the vast majority of their owners. That means that they make up less than 1%. They don't really consider this... the state of California has almost become a home owners association. I'm glad that Florida is on the "right" side of the country. : )

Yeah, they're under a lot of idiotic impressions. They barely let us swap or mod our cars, even though every swap out there gets better gas milage and emissions than a 20 year old V6. It doesn't make any sense. Theres no reason for any laws beyond what comes out of the tail pipe, but you should see how many we have, its ridiculous.

California sucks big time for car fans. What a waste of such a beautiful place to live...

quote Originally posted by Fastback 86: Yeah, they're under a lot of idiotic impressions. They barely let us swap or mod our cars, even though every swap out there gets better gas milage and emissions than a 20 year old V6. It doesn't make any sense. Theres no reason for any laws beyond what comes out of the tail pipe, but you should see how many we have, its ridiculous.

Not to hijack my own thread here... but whenever I watch "This Old House Classics" and they're restoring a house in California, they're always having to deal with local rules and regulations. Like one off the top of my head. You are not allowed to buy oil based paint in anything larger than a single quart. There was a small church that had been converted to a home, and they wanted to stain the floor of the great room. They basically had to buy like 40 some odd single quart cans of oil based wood stain.

Among other silly laws they had. Like another one that said.. if you wanted to buy stained glass for your home's exterior (doors, etc..) you had to buy it from their local art district. (The entire area was subsidized since they were craft artisans).

It IS the healthiest and cleanest state in the United States, so they are doing something right, but I think maybe they've run out of things to do... so they're just making up ridiculous things to make laws for.

------------------
Todd,
2006 Pontiac Solstice
2004 Volkswagen Beetle Convertible (Wife's Car)
2002 Ford Crown Victoria LX
1987 Pontiac Fiero SE / V6 5-Speed
1987 Pontiac Fiero SE / V6 (3.2L) Auto
1984 Pontiac Fiero 2m4 SE
1981 Pontiac TransAm (Olds 455BB)
1973 Volkswagen Type-2 Transporter

quote Originally posted by 82-T/A [At Work]: It IS the healthiest and cleanest state in the United States,

huh? based on what?

They actually did a test of the number of obese people in the United States, and California had the lowest percentage per capita than any other country. The state is very health concious. There were some other things, but that state was stated to be the healthiest and cleanest state in the US.

Actually... you know what, I take that back... it was by city, and they mentioned San Fransisco as being the cleanest / healthiest.

I think NY, NY came in second or third (probably because everyone has to walk everywhere).

------------------
Todd,
2006 Pontiac Solstice
2004 Volkswagen Beetle Convertible (Wife's Car)
2002 Ford Crown Victoria LX
1987 Pontiac Fiero SE / V6 5-Speed
1987 Pontiac Fiero SE / V6 (3.2L) Auto
1984 Pontiac Fiero 2m4 SE
1981 Pontiac TransAm (Olds 455BB)
1973 Volkswagen Type-2 Transporter

A Little back on topic. The plenum went to the welder today. I expect it back in a couple weeks.

Chuck

Todd did you get the picture I e-mailed to you? Can you post it here?

Chuck

O.K guys fierochild sent me some serious progress pictures...Here it is.

I'm still waiting for pics of the work done underneath the plenum.

**All rights and credit reserved to fierochild**

[This message has been edited by Mister (edited 01-29-2006).]