Bespoke Intake Manifold B202

[KPAero]

Cool to check and see the site back up, and a bunch of progress on this! Welding looks good.

[squaab99t]

Thanks Pascal,
It is progressing nicely. Nice to not be in a hurry. Systematically tooling and building one step at a time. Practice and dry runs to help feed the end product.
Will start designing and working the manufacturing process for the plenum. Might try some novel build techniques?

[squaab99t]

Some progress with a few more steps complete. Welded the back plate to the trumpets and faired the inner surfaces.
Moving on to the plenum. Need to decide on what material to build it from. Aluminum tubing and sheet metal or carbon fiber?

[Geoff]

Carbon fiber would be cool but maybe more of a PITA to make yourself than it's worth?
I wonder if there are any off-the-shelf plenums (aluminum or carbon fiber) that you could stick on to your runners?

Just grind off the logos you don't want?

[squaab99t]

I've definitely thought of the option to use something existing. Part of me likes that route, part of me says this project is for learning and advancing my skills.
Thanks for the images and ideas.

[squaab99t]

Update, primarily working on the fuel rail fitted and provisioned with a fuel pulse damper and pressure transducer port for the ECU to monitor. Stainless steel 9000 fuel rail, Injector Dynamic (Bosch Motorsport) injectors and my manifold design to live in harmony. Got the rail to fit fairly well with some minor adjustments and some spacers to find the injector and rail sweet spot.
Moving on the the rail ports. Went with a -08 AN O-ring Boss (ORB) and a -04 AN bung, all stainless too. After cutting the holes, took a try at silver solder brazing. I could have TIG the bosses, but I was worried I would overheat and debond the existing injector ports. The silver solder also gave me a chance to put another skill in the tool box. Came at decent for the first time in +35 years since I brazed. Some hand cleaning flux removal and finishing I was ready for a leak test. In a water bath, I took it to 15psi and no bubbles. Success, so I spun the dial to 11 and jacked it to 60 psi. The silicone plug for the ORB bung let loose and headed for the heavens in spectacular fashion.

[squaab99t]

Slo mo launch.
Have not found the plug yet.

[squaab99t]

Installed the fancy pants Radium fuel damper. Uses MAP ref on the back side of the diaphragm, so under boost it acts as a spring keeping the packaging tidy. The theory of the damper is to reduce the hammer shock effect of the injectors slamming shut creating pressure wave(s) which may inject more or less fuel than was expected. Some OEMs have fuel rail dampers stock.

[KPAero]

That all looks really good. The manifold look very nice linished back like that.

The 9000 rails are a really nice OE piece. For reference, maybe more for other people, I had no issues after welding an AN fitting in place of the return hose barb. The brazing is a nice touch though, very much keeps the factory look.

[squaab99t]

Well with all this excitement of the new injectors and low profile form factor, I hosed myself and created interferences with the cylinder head. Decided to flip the rail around and add new attachment tabs. Even with that the fuel return spud and hose will still hit the head. Next step was to cut off the spud and replace with a 14mm bung for a banjo bolt and fitting. End of the day I think I got it. Need to do another leak down/pressure test with all the rework that was completed.

[squaab99t]

Update on the plenum. A lot of cutting and sanding for fitment. Couple different CLR 4" tubing in .063 wall. Upper and Lower flat plates fitted and will add reinforcement features to reduce ballooning effect on the flat plates.
Practicing welding the type, material thicknesses and geometry.

[squaab99t]

The plenum had its first birthday back in November. Time to get jamming and make some progress.
Started by working on a design and spending a bunch of money on clamps, flanges, raw pipe and a DBW throttle body. 74mm Bosch DBW unit that will work pretty well with 3" tubing and Wiggins' clamp/coupling fittings.
Gotta love this warning signage. No management/engineers, only for mechanics.

Need to make an adaptor fitting/ferrule to interface between the TB and the Wiggins sleeve and clamshell.

[squaab99t]

Happy Easter everyone. Hope you have the chance to spend time with your love ones.
Time for an update. Rebuilt the plenum from scratch as I was not happy with the first version's direction.
Spent a lot of time on the fitup to make welding easier. Thin material and butt joints can keyhole out in a blink of an eye. Worst if there is a gap.
Welded out okay. Certainly not the Best on the Net, Raul. Time to check if the welds were water tight and if it could handle the internal pressure. Proof test target set for 40 psig, about double the working pressure.
I was originally going to do a bubble test. Pressurize the vessel and look for leaks in a tub of water. Ran that by some friends and they said Bad Idea. Too much energy stored up in compressed air and a rupture could lead to frags and other nasty events. Flip it around, top off with water and use a small volume of air to pressurize. aka Hydro-test.
Needed to build some fixture to contain and introduce the pressure. Pretty straight forward except for the cylinder head backing plate. Chased leaks 3-4 times until I came up with a water tight solution. Stiff plate and RTV.
First try I did find a single pin hole leak at a meager 10 psig. Ground that out and rewelded. Back to the test...

[squaab99t]

Fixtures: T/B cap with fill port and gauge

Back Plate with the rectangular tube. I tried the 1/8" sheet first, but it flexed too much even with three clamps.

Old injector and rail to plug the ports

Topped off with water and ready to cap. Actually let the water stand for about 15 minutes to see if the level dropped? Good to go.

[squaab99t]

Simple bike pump since I did not need much air volume and a nice controlled accent in air pressure.

A friend with a dial indicator and magnetic base helped measure the deflection of the flat plate area where we assumed would be the most ballooning. About .045 inched each side. A total of 3/32" or 2.4 mm. You could physically see and feel the contraction when the pressure was released.
Next time we will use a dial indicator with more throw.
Happy to say no leaks or ruptures a two times the working pressure.