My thought was to sorta steal Goatnipples2002's idea. It looks like this:


My question is, Why couldn't I attach short runners to the bottoms of the plenums so that I don't have to hack up the lower intake? Or would that basically defeat the whole purpose?

Anyone else ever make anything like this? I'd ask the creator but he hasn't been around in 3 years .

 

pictures dont work

 

I can see them.


It looks like a good idea. I hope you would make it look nicer, maybe larger TBs and runners for those with turbo cars.

 

While talking with me dad last night we actually came up with a very interesting idea. I am going to try to come up with a pair of plenums like above but with smoother, straighter runner kinda like in this drawing. Excuse the poor artistry, I never did pick up the drawing ability. It's drawn in pen, but there is an attached picture.
Thoughts?

 

I will be eventually making one for a twin turbo 3.4/3100 hybrid I'm slowly building.
Project89 can you see the pictures linked below?

The more i think about it the more I am thinking that this set up should be on a hybrid motor. The iron heads will restrict success. Though I am thinking of building a very similar model to the one above for the 3.1 currently in my convertible, I am thinking I will build something similar to the one pictured below for my 3.4/3100 hybrid.
On that note, is a 97 3.1 a Gen II or Gen III? Is there a way to measure the
valves to find out which it is?

The picture below is a quick and dirty rendering(gotta love MS Paint). The left is a drivers-side view the right is as close of a straight on view as I could do. the idea is a nearly straight shot from the throttle body to the intake valve. Would that be too much air?(is there such a thing)

 

Id use square, tad more volume, easier to deal with mounting flanges n such.

 

piece of flat stock with 3 inch tubing sliced in half for the plenums , and they shoudl taper down as they reach the rear cyls

yeah i see them now it was the pictures i thought they would be

 

Ya that was my first thought too Gumby. gonna have to figure out a way to go round for the throttle plate to square though. Project89, that is the current hang-up. I am trying to find more instances of others doing similar things to try and figure out how much taper is ideal.
From everything I am finding online, the longer runners of this design would be great for low end torque but bad for the higher RPM's right?

 

You would be better off keeping a single plenum, but making it larger than stock.

I would look at modifying the runners, and lower intake along with the upper more than just doing the upper.

The intake modification in the above pictures shortens the runners slightly, which in theory will reduce the low end torque slightly, and move the RPM band up slightly, but some testing would need to verify. The size of the plenums looks like it would be marginally larger than the stock plenum. Basic rule of thumb is that you want the plenum volume to be 2 to 3 times the size of the displacement of the engine. Most plenums are not any where near this.


I'm toying with the idea of going with two separate plenums on my car as well, but more for ease of access to the fuel rail, than any performance gains.

 

[QUOTE=Six_Shooter;5864430]You would be better off keeping a single plenum, but making it larger than stock.

I would look at modifying the runners, and lower intake along with the upper more than just doing the upper.

The intake modification in the above pictures shortens the runners slightly, which in theory will reduce the low end torque slightly, and move the RPM band up slightly, but some testing would need to verify. The size of the plenums looks like it would be marginally larger than the stock plenum. Basic rule of thumb is that you want the plenum volume to be 2 to 3 times the size of the displacement of the engine. Most plenums are not any where near this.


I'm toying with the idea of going with two separate plenums on my car as well, but more for ease of access to the fuel rail, than any performance gains.[/QUOTE

Ya the dual plenums are more for a "wow that's cool" factor than speed factor.
So for plenum size it should be around 6272cc to 9408cc is our engine is a 3136cc like wikipedia indicates? Do you know how long the stock runners are?
The easiest way for my plan to work is to either machine a middle intake till just the base is left or find someone who can machine me a plate to mount the lower intake(the piece that connects to the heads).
My runners will cross from there at as close an angle to the intake ports in the heads as possible to near the valve covers on the opposite side of the block.

 

I wouldn't criss cross

 

Why is that? I was just replicating the stock design there but with longer, smoother paths for the air.


Would it be bad if the path is too smooth/straight from the throttle body to the injector?

 

something like this would be simple to build and helps a ton over stock






put a v diver in the middle to taper the volume down to the rear runners

u could build a few out of steel for testing really cheap

 

Ya that is true too. The main reason (besides what is supposed to be a nice increase of performance) for the twins is that I have never seen anything like it in a Third Gen before. Even those pics i posted above are out of a Fiero.

 

id X them if they cross, same as an X pipe. each cylinder can draw from both.

 

And this is exactly why i posted this here for debate!! Thank you Gumby, for it wasn't until I started to argue why I thought the criss-cross was a good idea and uploaded those pictures of the lower intakes did I realize a serious flaw in my design!! The runners cross in the lower intake so crossing them again adds a turn. The only way the criss-cross design works is if I attach it directly to the heads. Which isn't going to happen. In reality it neds to be like below!

Project89, how much does one of the "Pizza-box" intakes help?

 

mine had very large plenum volume so i lost some throttle repsonce but it helped alot specially on the top end . its hard to say just what it will do on an n/a engine as i built it for a turbocharged engine , but off boost power was deffinatly improved

 

Interesting. I may have to play with a few different designs. Though I am going more for low-end torque. This will be going into a DD turbo car. I have a Camaro that will be getting the V8 race-car treatment.

 

Hey will this set up work with a 252 cam and 1997 roller rockers work in stock 3.1 heads?

 

260+ cam with the pizza box would be best

 

Thank you Project89. i will probably build a Pizza box for this year, but I really want to see if I can figure out a way to get this set-up to work. Many have tried over in the Fiero world, but there are only 7 working examples that I know of. There was a company called Street Solutions who, for a while sold these as kits, but they have since disappeared as far as I can tell.
Their kit is almost exactly what I am planning on doing though.
[IMG][/IMG]

 

And really I was over thinking several issues with my design. I am going to copy theirs withe the TPS. They simply hooked the TPS cable to the left throttle body then connected the output shaft of that throttle plate(where the TPS sensor should be) to the throttle plate on the right plenum with an adjustable rod and ran the TPS sensor off the right throttle body.

My question is this: could I mount a fitting on one IAC cover and run a line to the other IAC cover to also only use one IAC? that is the only thing not covered in the walk around of the kit mentioned above.

 

Just use two IACs.

 

Can I add a 5V constant and an input pin to the ECM? Or would t-ing the input and 5V constant to each be OK?

 

Wild guess on taper, first section needs to be 3in right for TB to mount? then have it taper down to half, 1 1/2inches. But put the last port on the 2in line. See he has allot of over hang, move some back.

 

What? Why are you worried about adding any 5V constant to anything?

Just split the 4 IAC wires and run both IACs...

 

Doesn't the IAC get a 5v constant from the ECM like the TPS does? OK that simplifies things

 

No, it's a bipolar stepper motor, the signals will reverse polarity, depending on which direction the IAC needs to move.

 

Oh OK. Cool.

 

OK cool! Thank you

 

Does anyone know how these custom intakes effect fuel milage and drivability on the street?

 

depends on how the intake is designed , and how the rest of the engine is setup

when building an intake u pick ur parts for the engine first and build ur intake last

 

that intake is simple to build really, but there really is no need for dual plenums and tb's

if u want an easy start to a dual plenum intake get the upper intake off a 3.4 and cut it up

 

The plan(as long as the block isn't junk) is to have a 3.4L punched .0196 over with dished FWD pistons and stock lower internals. 3100 hybrid top end out of a 2001 Malibu Stock 1.6? roller rocker arms and a 260 grind cam. I will be custom building a set of headers at some point too. Backed up to the stock auto trans with a B&M Hammer shifter in the car. Ideal peak power would be 5,000-5,500 RPM.

Do you think there is a chance of comparable-to-stock fuel milage yet a bit better performance with this set up?

 

Does 13.69 :1 sound right? According to my calculations, the dish have on these pistons: h847cp 50mm (.275 in deep by 3.18 in diameter) is 2.18 cc. With that and the .0196 over bringing the bore up to a 3.6396 over the 3.62 stock and a stroke of 3.31 in. That makes it 206.55 CID on the summit racing calculator. With the FWD pistons are .02 proud of the block at TDC and a .06 thick gasket. The cylinder head has a volume of 28.6 cc on a 2001 Malibu, right?

This is according to the calculator on summitracing. com. Did I screw up somewhere?

EDIT: after converting the piston dish area from cubic inches to cubic centimeters it comes out to 8.23. Does that sound better?

 

Using the (stock) gen3 pistons, heads and head gasket you should have an SCR around 9.5:1.

 

So that should be about right then with the slight increased bore size. Are the FWD stock pistons dished or just shorter?

 

That increase in bore should not drop the SCR that much.

The FWD/aluminum headed pistons have a dish, due to the smaller combustion chamber compared to the RWD/iron head version.

I'm not sure there is much of a piston height difference between the different versions. There's a difference in pin height between different variations (displacements) of the 660 though.

 

Ok. Thank you.

 

After doing some math, I discovered that the intake runners on a 2001 Malibu 3100 are way bigger than the needs of that engine as far as ideal size goes. From what I can find Max rated RPM is around 6000, yet the crosscut intake runner area is big enough that you would have to run a motor bored .02 over like mine up to 6500ish RPM in order to the the true "tuned intake" effect!

 

Hey quick question. Can I use this datalogger:
to log the data on this intake set-up? or will it not work for a V6? Is there one that would be better recomended?

 

Yea that will work. You planning to use tunerpro Rt?

 

Ok, thank you. I was actually planning on getting this setup from another member of the boards here:
Batronix BX32 USB EPROM programmer, works great, software is free off of www.batronix.com. Great for the DIY EFI guys on here and best part its USB!
Will a data logger let me see anything that my professional scan too won't? The scan tool can see the readout from all the sensors, but can't really save it.

 

I don't know what you'd be paying for that used Batronix programmer, but there are less expensive options comparing new prices that will do as much.

A datalogging (and tuning) software like Tuner Pro RT offers a lot more functionality than a stand alone scanner, because you can save and later review logs, along with a feature that I use often called "tracing" where in real time (or even when reviewing a log) a bubble floats around maps to show exactly what cells are being hit at that point to make tuning easier, along with showing real time data next to scalers helps immensely.

 

OK thank you. He wants $105 shipped.

 

Yeah, I would buy a Willems GQ series (GQ-3X, which has no case, or GQ-4X which does have a case), if I felt I needed to be able to program more than SST 27SF512 EEPROMS and a couple other EPROMs that the BURN2 will program. BURN2 is $85 + shipping, and interfaces directly with Tuner Pro to automatically set the proper offsets for each bin file and EPROM size used.

 

OK thank you

 

Hey Six_Shooter, that Willems GQ 3-X is only for burning EPROMS, right? Or can it do the "real-time" in car tuning? What would I need to do that and is it even necessary to tune that way?

 

A programmer is not an emulator.

An emulator serves a different purpose.

I use a couple products from moates.net, the Ostrich 2.0 or AutoProm. The Ostrich is an EPROM emulator only, where as the AutoProm has emulation, datalogging and programming functions all in one device.

 

Do you think I will notice a difference if I were to put a Comp Cams 252 cam, 1.6 roller tip rockers, and Fiero valve covers in my 3.1 V6?
Can a set of roller tip rockers out a a 350 be used in a 3.1?
Will the stock valve springs work or should I be looking at replacement?
I will have a Custom Chips Inc. "stage 2" chip made by a guy from Facebook named John Wayne.