This a bit of a continuation from both the head mods and flow work so the first few pics will be re-post from those sections to give you the starting point
[h1]Making the Intake Manifold[/h1]
My first thought as to use Suzuki Hyabusa TB mounted to a cross-flow intake and it looked good in theory. This would mean curving and flattening the intake runner to make the crossover work but it seems doable….until the flow bench said I really needed bigger TBs
I played around with a test runner from clay and then a chunk of aluminum and the TBs will fit but the ports need to move up in the head to make it work right…..off to the head re-work thread
With the ports moved and a mounting flange installed I can get back to work on the intake manifold.
I want the TBs to be sitting square so I can make an airbox that drops on so the intake runners will need about 20 degrees of sweep. Also the port is pretty oval and the TB only a touch oval so the runner needs to both sweep and have a variable section shape….not an easy task but most anything is possible in fabrication land.
My plan is to make each runner from 3 pieces of tubing that are crushed to varying amounts of oval to creat the section change then mitered and welded to create the sweep. I’m going to build the runners from ¼” wall tubing to give me plenty of material to work with....because there is going to be a LOT of grinding to be done.
Lower mounting flanges. These are just a question of milling big holes in the ½ x 2 aluminum and drilling the mounting holes. I decide to leave the port holes a bit undersize and only drill the center mounting hole then do the finish work after I weld on the runners thinking that the welding will most likely shrink the flanges a bit.
Flanges done and it’s time to fit the runners.
I made them plenty long, now they need to be measured and cut to close to finish length…the actual finish cut will be done I the mill after welding but the bandsaw will get rid of most of the excess fast and easy.
Once the runners were all welded on I thought the assembly in the mill and cut the runners to finish height.
Next comes the top flange. I weld prepped the inside to the runners and drop on a ½ x 4 plate and welded the outside. The inside will get welded after I machine some holes so I can get in there.
With the bulk of the welding done it’s time to machine. I did the top flange first an started by flycutting the surface so the TBs will sit level. It took me 2 tries to get right….it turns out I’d made a slight error putting the flanges on the head, but not a big deal and it all came out fine in the end.
With the flanges now right I Drilled the TB bolt holes, bored to accept the (shortened) TB snout and rough open the hole into the runner.
Now come the fun part. I want the flanges profiled to match the TB bases but I don’t have a CNC…..so I had to do it the hard way. I blued the flange, bolted the TB on, scribed around the TB base, then milled to the lines. It needs a quick sand to smooth it a bit, but I think it came out pretty good.
I did the second one the same. I also flycut the bottom flange, blued it and profiled it to match the flange on the head.
Everything fits and the TBs look GREAT!
[h1]Mounting the TBs[/h1]
With the Manifold done it's time mount the TBs. On the flow bench I settled on 54mm Ducati 749/999 TBs. While building the intake I decided I wanted the TBs rigid mounted vs. the rubber mount Ducati uses with a bonus that this allows me to shorted the mounting snout on the on the TBs and save some space.
The TBs have a couple issues for inline use. First is the width…..they bang into each other long before they fit the Ferrari 94mm bore centers. After that there is the question about linkage and making that fit.
The first step is to get them disassembled. The throttle shafts need to come out any way because the flow bench says the stock round shaft is bad so all 12 will need to be milled flat.
Getting the TBs apart proved to be a bit of a challenge. The screws the hold the throttle plate are peened but a quick grind and they came right out, the issue was the TSP (Throttle Position Sensor) that was on ½ the TBs. The TPS is pressed in and the only way it comes out is broken….unless you grind the entire TPS mounting boss away, which I did on 4 TB figuring I need to cut4 or 5 of the bosses off any way to solve the spacing problem and I’m too cheap to buy a new TPS when I have good ones that just need to be removed.
Disassemble TBs, check.
[h1]Making the Airbox[/h1]
As cool as the engine looks with 12 huge TBs on top, it needs and air cleaner so I’ll need to cover it with an air box. One of the goals of this project is to keep everything looking as stock as possible so my thought on the airbox is to start with a chuck of an OEM QV plenum I have kicking around and re-work it into the V12 airbox.
The first step is to drop the engine in the car and measure exactly how much room there is to play with….and admire the 12 HUGE open TBs
It looks like just a touch over 3” to play with and with some hood trimming I could easily get 3.5 or maybe even 4”.
Here’s the OEM plenum chuck sitting on top…looks a little sad but I think it will work with some re-working.
The plenum needs to get bigger…and I think the best way to make that happen is to start by sawing it up a little bit and adding a piece to the middle.
Now it needs to get wider and it needs sides.
Next I need to decide what to do with the center part.
My first thought was to mill a shield and put a horse in the middle to fill up all the space and give it that “I came out of the racing department” look.
This caused a lot of reaction for other ferrarist suggesting I simply continue the ribs across.
I settled on ribs for the airbox…..because it was easier to do and the airbox top pretty much finished. I rewelded the sides (I ground through the weld in a couple places), welded the diagonals, milled the ribs and cleaned it up a bit. I don’t have anything to sand with that gets in between the ribs very well….I’ll have to search around and see what I can find.
The air inlets are next up and were this morning's work....which was really mostly just looking at parts and thinking a bit. There is going to be a 4" or 5" hose feeding each end of the air box. I want the top to keep its shape and definition so the blends to the hose connections will be biased to the bottom as much as possible.
The top of the airbox will be removable because I will be using show injectors mounted inside the airbox. I was thinking I wanted the air hoses attached to the bottom plate to make the top removal easy….as I could pop it off to show off my 12 massive throttle bodies , but that will make sealing the top a bit of a challenge I think…..I need to give this some more thought.....I may move on to something else while I ponder the plan......
The air hoses will go the a pair of air filter boxes mounted behind the engine with hoses running up to the body air inlets. I’m trying to make the install appear stock so I’m thinking I’m going to try to use a pair of OEM CIS air filter boxes or at least the covers from them…..we’ll see.
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