The needy noob is back.
 

Hello interwebs! I lack boost still pushing 5psi. I needed a new clutch, better tune, and allumium rad first. Finished all that this week. I'm running a td04hl-15g with a nice taco taco mani. I have reason to believe that my MBC is not working. I keep turning it and TS still says 5psi same with my boost gauge.

I'm going to post my finished pics up of the build. Also, can someone double check my MBC set up. MBC to wg and to compressor housing. Might be hard to see the compressor pic. It's the lower line with brass barb. https://cimg4.ibsrv.net/gimg/www.mia...1a0e2bd681.jpg

https://cimg8.ibsrv.net/gimg/www.mia...1cad99bcee.jpg

https://cimg5.ibsrv.net/gimg/www.mia...b2b1c7d01a.jpg

https://cimg6.ibsrv.net/gimg/www.mia...cdb13dc67b.jpg

Could be your boost controller, could be your diaphragm, could be boost leak, could be a miscalculation.
When I first put my turbo I thought it was making around 20+psi of boost until someone told me you have to subtract 100 kpa for atmosphere so I thought I was making like 4, but at my elevation its only 86 kpa, so it was right where it was supposed to be (8 psi no boost controller, just spring pressure)

It's was 5psi without controller. Installed controller and it's still 5psi. I checked all the ic pipes for leaks. Don't even know what a diaphram is of where it is lol.

lol

That's a regulator, it lets all air pressure up to a certain point pass through and only then will it act as a restriction.

How are you going to use that to increase boost past the wastegate setting? It always leaks pressure, there's no way for it to clamp down 100% and only pass pressure greater than 5psi.

The simple answer is it physically can't. You did it wrong.

I figured it was wrong... Although I followed the directions that came with the controller. How do I hook it up so it works?

It's not going to, I don't think. Is it an actual boost control or a regulator from lowes? It looks like a air compressor regulator, which won't work.

It's a turbonetics boost controller from aa auto.
https://m.summitracing.com/parts/tnt-10402-25?seid=srese1&cm_mmc=pla-google-_-shopping-_-srese1-_-turbonetics&gclid=CjwKEAjwiru9BRDwyKmR08L3iS0SJABN 8T4vKI4GZURkFf3yBGo4ZIW80emk7hfh8PrjYoKbNhGHYRoCeH nw_wcB

Always the last place you look lol... Since I couldn't find a leak I tried to readjust the recirulaating valve hose. Noticed a hairline crack. Popped it off with a little pressure for the pic. That's right before the throttle body. The upper rad hose got in my way when I was looking for leaks. https://cimg2.ibsrv.net/gimg/www.mia...ebabec1642.jpg

Nice prop rod!

They don't say much about it, but I swear that's a dam compressed air regulator. It even has the "pull to adjust" cast into the cap. So that's about $20 in parts you just paid $107 for? It must suck to suck.

And although that pipe is a boost leak now, the hairline crack that it was, probably wasn't large enough to be a significant boost leak. That's not your issue.

Also-

"Change your boost level from the cockpit of your car with the Turbonetics VBC kit. The VBC kit can adjust boost pressure on any external wastegate or factory dual port actuator. Adjustable from stock to the indicated pressure above stock. Dual port actuator only."

https://turboneticsinc.com/store/ind...product_id=406

I looked up the install directions and couldn't make sense of it. Using certain sized brass t's for different boost ranges?

Only way I see something like that working is if it's a bleed type boost regulator, which means it might be a very low pressure regulator and those are usually more expensive.

But I guess if it's only for dual port gates it makes a little more sense...

It must be. Would explain why they are making you use different fitting as orifices. Could have done so much better for $107.

Suggest something for me. I wanted a MBC and didn't want to wait for Amazon prime. I didn't care about the 100$ that much. I knew my impatience was costing me to pay a hefty premium. I could probably still return it.

I suggest you try this

Attachment 183510

Close the valve 100%, then slowly start opening it, should bring the boost up.

Or you can make an adjustable check valve, like this here

The"D.I.Y."Manual Boost Control

Ok. I'll give it a shot. Btw, here are the actual instructions with the unit I bought.
https://cimg6.ibsrv.net/gimg/www.mia...fd6682dbf4.jpg

Yeah, you bought a piece of junk worth about 20 for 100. return it if you can.
run a ball/spring mbc like everyone else.

you want a really good one without having to build it? hallman pro rx. use it on the cars that need a mbc. works perfect, every time

So, they sell the homemade one on Amazon for 22$. For a 12psi set up what would be the advantage of running the hallman version for 90$? I'm probably going to make it today tbh.

All done. Returned that pos and I looked at the receipt noticed the price was 200$. They price matched for me when I was there. When it was working the boost levels were inconsistent anyways. I made the ball and spring and for the first time the build feels complete. Now let's see how I do at the next autocross @ Pocono. Thanks guys.

the hallman would be more precise and stable, just overall higher quality and more precise operation.

but the DIY setup is fine, I've used it before and it works. glad you were able to return the junk one