Well, I HAD wastegate creep...
#1
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I just installed my DIY MBC! Big it up for Braineack's FAQ!
Sheesh, it changed things a bit! When I first put it in it was a little tight and I didn't drill a hole in the back, so it was spiking to 10 and settling at around 7 PSI. I took it out and drilled a little hole and went for another spin... My boost gauge got to 14 PSI for about a second before I removed some right foot. I tweaked it a little and now I have a fairly steady 8.5-9 PSI by 3000rpm and all the way to REDLINE.
And it comes on like a train, not trickling on like it used to. I'm still on the stock exhaust cat-back, so when that goes in the bin and my 2.5" system goes in I'll be a very happy camper.![yippee](https://www.miataturbo.net/images/smilies/yippee.gif)
Thanks again Braineack and to the forum!
Who else has a DIY MBC?
![bow down](https://www.miataturbo.net/images/smilies/bowdown.gif)
Sheesh, it changed things a bit! When I first put it in it was a little tight and I didn't drill a hole in the back, so it was spiking to 10 and settling at around 7 PSI. I took it out and drilled a little hole and went for another spin... My boost gauge got to 14 PSI for about a second before I removed some right foot. I tweaked it a little and now I have a fairly steady 8.5-9 PSI by 3000rpm and all the way to REDLINE.
![Biggthumpup](https://www.miataturbo.net/images/smilies/biggthumpup.gif)
![](https://www.miataturbo.net/images/smilies/cool.gif)
And it comes on like a train, not trickling on like it used to. I'm still on the stock exhaust cat-back, so when that goes in the bin and my 2.5" system goes in I'll be a very happy camper.
![yippee](https://www.miataturbo.net/images/smilies/yippee.gif)
Thanks again Braineack and to the forum!
Who else has a DIY MBC?
#5
Boost Czar
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yeah I need to add the "hole" to my instructions...good job. Glad you were at least able to put it to some use. I've been rocking to same one since I built one for my 626 Turbo a few years back.
#7
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I'm assuming this is a ball and spring type controller? You can add the bleeder hole in the line leading back to the wastegate instead of making a hole in the MBC body itself (if memory serves me correctly, I didn't drive that car today) by adding a plastic connecter joint with a small bleeder in it (I used a hot needle to make the hole in the plastic.) A leak check on my DSM revealed I was losing boost through the bleeder hole on the MBC all the time. I JB welded the bleeder hole and moved it down the line - problem solved.
#9
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I've got the VooDoo eBay special, and it's awesome. I still have about a 2psi drop in the higher gears... but that's OK. An extra 2psi in the midrange makes for great torque, and then a slight dropoff up high makes for less knock threshold. I don't mind it so much.
I drilled out the hole a little bigger than it came with... plus I expirimented with swapping the ***** to both sides. One of my ***** is bigger than the other. I wondered why? I would have thought that both the ***** inside would be the same. It seemed to make no different which was on what side of the spring.
Does anybody know?
I drilled out the hole a little bigger than it came with... plus I expirimented with swapping the ***** to both sides. One of my ***** is bigger than the other. I wondered why? I would have thought that both the ***** inside would be the same. It seemed to make no different which was on what side of the spring.
Does anybody know?
#10
Boost Czar
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I think the ball on the threaded side was just the help keep the spring planted. No chance it can catch on the threads of the adjuster or get crooked inside....something like that.
Put the larger one on the bottom to help seal it closed.
Put the larger one on the bottom to help seal it closed.
#11
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I was/am using a Joe P. boost controller. I'm assuming that it was probably drilled improperly. I'm just offering another location for the bleed hole for those who don't want to drill into the MBC body. Having driven the car with the bleed hole removed entirely, I can tell you that having the bleed hole on the ball/spring controller is a necessity and increases boost response between gears tremendously.
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