How to build your own Manual boost Controller.

Seeing as I could find no recent guides for building my own manual boost controller, I submit to you my simple instructions. This guide does require a basic knowledge and access to tools and should only be attempted at the users own risk.

The Parts List:
1) ¼” Female Pipe Tee
2) 2x 3/16th x ¼” Hose Barb Adapter
3) 5/16th Hex Nut
4) 5/16th 1” Cap socket Screw
5) ¼” male to male coupler
6) 1 3lbs spring
7) ¼” Ball bearing

The Tools List:
1) 9/16th end wrench
2) 5 1/6th Tap
3) Teflon Tape
4) Hack saw

Assembly Instructions:
Open all the packages and lay out the parts. The idea behind this boost controller is the ¼” Tee is the body, the 2 hose barb adapters are for the vacuum lines, and the ¼” coupler, hex nut, spring, and bolt are the controller. It is assembled as followed. The adjustment of the bolt allows the spring to press more or less on the ball bearing allowing the change in when your wastegate opens.

The build photos:

The parts on the left, the tools on the right.


Close up of all the parts we are using.


Here is the layout of the MBC. Hose barb- ball bearing- Tee- Coupler- Spring- Nut-Bolt-


Now the first step is to cut the ¼” male coupler as shown. Your basically removing the threads from one side.


The second step is to tap the remaining ¼” coupler with the 5/16th tap. Use plenty of wd40 or cutting oil so it goes smoothly, and be sure to go all the way through.


With the coupler cut, here is how it fits onto the assembly.



Now take the Teflon tape and wrap the male threads on the hose barbs and coupler.


Assembly is very simple, just loosely tighten the hose barbs into the tee, insert the ball bearing, next the spring, then the coupler and finally the bolt with stopper nut. Use your 9 1/6th end wrench and vice to tighten it all snug.


All finished. Now I used a 1 ½ bolt, I would suggest getting the 1” instead. I have not tested this, but will be later in the month.


Total cost:
$10.78

All parts were available locally through Home Depot, except the ¼ ball bearing. I found this at a local farm supply store. I hope this has been found use full to some who have been requesting a guide.

 

hey....where would u go about getting the spring and the ball....i dont think home depot or lowes stock those on their shelves

 

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Thanks dub . I wouldnt use this thing past 15psi as many guides online warn.

I may end up replacing the spring with a different one, I dont like how flimsy this one is. Back to Wilco..... (Farm supply store mentioned)

 

I've seen people build them before. Good write up on it.

 

Thanx for giving people an excuse to blow their cars up now...


-Ted

 

I made one of these and I had a problem with the barb I used. anything over 5 psi made the ball bearing just spin and bounce off the walls, then sit in the barb opening.
this would effectively prevent any air from getting through, thus making the controller useless.

After looking at it for a while I noticed the hose barb had a deep angle to the seat where the ball bearing sat and this caused the ball to do what I mentioned above. I tried fixing this with a rubber o-ring and then a flat rubber washer, but I couldn't find a flat one that fit right.

Bottom line, be carefull when buying your seat barb and make sure the inner surface is flat, not angled.

Another good place to get ball bearings is a bike shop, they gave me mine for free. Also, home depot has little packets of springs, the one I got was a variety pack that contained 2 each of three different stiffnesses.

 

I'd really suggest not using this setup. The spring is too skinny for the housing, so the spring will deform and flex into the cavity and then it'll just leak.

 

Jerry's has a whole wall of springs to choose from, I found one that fit perfect after I gave up on my setup. oh well.

 

Haha, I could never find a spring that would fit the ball, and was still wide enough to not bind/flex in the cavity, this was why i just bought one on ebay for $10

 

Are you that poor? If so, you probably shouldnt be using a MBC in the first place. You can buy a pretty good MBC for next to nothing.. Ted's kind of right, all of the 16 and 17yr old TII owners on this forum are going to blow up their stock cars this week due to you.. j/k..

 

thanks for taking the time to post a good write up

 

I went back to the supply store I got the ball bearing from and found a proper spring- your angle problem was also probably because of this weak origonal spring. Make sure if you do this, you find a proper spring. This was the only avalible brass T at home depot, if you can find another suitable one with a smaller inner diamiter, the spring listed should work.

Like I said, this should only be attempted at the users own risk.

 

Yeah, I eventually found a T with a skinny inner section that I drilled to the diamater of the spring so it wouldn't flex inside, was the only issue I ran into, the thing has been working great ever since.

 

you can all so make them out of fish tank pumps lol

 

Eh? This is the same way alot of manual boost controllers that you would pay $100 for are made. I don't see how anyone who does it right and has a boost gauge will blow up thier car.

-Joe

 

idiots shouldnt be owning rx7s anyway...let them blow up their motors and not wreck them. this way we have rx7s lasting longer in the future....good post

 

You ever tried to adjust one of these things?
Aren't they mounted in the engine bay?
Adjust...go out for a drive...stop and pop the hood, adjust...go drive...


-Ted