Why can't I hold boost??

[jeffmsp]

is the line inside those plastic covers?

 

[TurfBurn]

No, I think I have the line removed in that picture as I have the engine and pretty much all the vacuum line out of the bay at this point. There is a large nipple in the region I indicated in that picture that has a line coming off of it normally and that is the line we are talking about.

 

[Glowmunkey]

I'd hate to be the bearer of bad news for ya, but its not the boost controller that is the problem. I have an electronic boost controller (Blitz Dual SBC Single Solenoid), and the boost still falls off to about what you are seeing as well. I hit around 10 psi, then by the time I get near redline, it has fallen down to the 7 psi area.

I got a new corksport exhaust (starts where the apex downpipe starts and goes all the way back), and that helped with bringing boost on a bit earlier, but it still drops off. Granted, it used to drop off to 6 psi and now it drops only to 7 psi, but that is still a drop-off.

So, basically, its a common problem because of the size of our turbo, I believe.

My MBC from Turfburn does exactly the same thing. My Joe P does not do it anywhere as bad, but it does spike (spools faster too). My car may just be a freak, I also fixed most of my 4000 rpm hesitation by removing my FCD. Exact cause of these issues? I dunno at this point. I'll get it eventually, but I haven't had much time lately.

Thinking it might be time for a wideband and stuff so I can really learn what the deal is. This would actually be a lot of fun if parts were free...

 

[TurfBurn]

My MBC from Turfburn does exactly the same thing. My Joe P does not do it anywhere as bad, but it does spike (spools faster too). My car may just be a freak, I also fixed most of my 4000 rpm hesitation by removing my FCD. Exact cause of these issues? I dunno at this point. I'll get it eventually, but I haven't had much time lately.

Thinking it might be time for a wideband and stuff so I can really learn what the deal is. This would actually be a lot of fun if parts were free...

Yep, the JoeP will spool faster than ours (why we have a wastegate controller so you can adjust spool up and limit any spiking induced by spooling the turbo too fast), but we sacrificed that for better boost consistency. Why yours and Gboro's fades off I don't know... that is the big issue that needs to get figured out and I'll be testing to see if what I can find! I do appreciate your guys' understanding and hope that at the least you've been happy with our service if nothing else!

I will update any time I get any news or we figure out the source of the oddities.

Thanks much!

Steve
sales@nsnmotorsports.com

 

[Aaron]

mine still works great Steve.

only drops about .5 psi from my setting in the upper RPM range.

Thanks for a great product.

 

[Glowmunkey]

Yep, the JoeP will spool faster than ours (why we have a wastegate controller so you can adjust spool up and limit any spiking induced by spooling the turbo too fast), but we sacrificed that for better boost consistency.
Steve
sales@nsnmotorsports.com

Yeah, I know, can't really have both... ah well.

 

[gboromsp]

Very pleased with your service. And i'm not convinced that it is your product. It may be something that i'm overlooking. When fall break comes around in a couple weeks I plan on trying to get the issue solved.

Yep, the JoeP will spool faster than ours (why we have a wastegate controller so you can adjust spool up and limit any spiking induced by spooling the turbo too fast), but we sacrificed that for better boost consistency. Why yours and Gboro's fades off I don't know... that is the big issue that needs to get figured out and I'll be testing to see if what I can find! I do appreciate your guys' understanding and hope that at the least you've been happy with our service if nothing else!

I will update any time I get any news or we figure out the source of the oddities.

Thanks much!

Steve
sales@nsnmotorsports.com

 

[SirJaime]

JoeP MBC

I had to tske my MBC off cause my car "is/was" riding @ 15+ after I put my 3" cat-less exhaust on from Apex. Then I tryed it again and hit just past 10 and the damn fuel cut shut me down then it did it again so I pulled over to reset my JoeP MBC and went down the road again, no spike just a steady 15+ till I chickend out, "don't want to blow my motor".

So. I stopped again to turn it all the way down but with no luck so I dorve home with it like that and took the damn thing off, So... now I'm just killing time till I go for a ride again. Took me most of night and som of the morning to put the pipes on with a small floor jack.

I know Apex tech's need to put that extra bend in that third joint to go over instead of under, but like it is there are only two bends in it other than the S-pipe and the J-pipe.

Anyway I have no ideal why other than its a FREE FLOW now.

p.s. Sounds Damn good to.

 

[TurfBurn]

Hmm.. there is no reason the JoeP should have done that. It is holding a standard 7 psi of boost now without a problem? I don't know what would cause that unless it is spiking that bad from the better exhaust flow. I think Joe would have an answer for you... you may just need a lighter spring or something, but it doesn't really make sense.

Hope you get it figured out though!

Later

Steve

 

[SirJaime]

Hmm.. there is no reason the JoeP should have done that. It is holding a standard 7 psi of boost now without a problem? I don't know what would cause that unless it is spiking that bad from the better exhaust flow. I think Joe would have an answer for you... you may just need a lighter spring or something, but it doesn't really make sense.

Hope you get it figured out though!

Later

Steve

I found the prob. It had to do with the better air flow, and... that I had not reduced the JoeP. And when I did "dumb ass me" I turned it clockwise and turnning the boost up instead of counter clock to turn it down. Yeh I'm glad I keep that manual that they send with the MBC.

I finale took it back out for a ride with out the MBC and nothing but spooling up faster. So.. I said "the hell with this" and but it back in after rereading the manual Now it SPIKES back @ 10 and drops as normal.

(rockon) Live and LEARN

 

[Brian MP5T]

i had a defective mbc once, that was the problem. it would boost to 8psi and then creep down to 4psi (the size of the wastegate spring)

Same problem, however mine worked great for a year and then did this...
I changed to a 12.5 Psi spring and then set the higher setting on the MBC to 15. Under WOT, the pressure holds, If I let off a bit, you can see it fall slowly. I'm geting an E-Controller in the new year, **** this cheap MBC s***!

(rockon)​

 

[Brian MP5T]

 

[SirJaime]

holding Boost

Dude have you tried third fourth & fith to see it it will hold. I found that 1,2 & 3 wind out way to fast to really see th boost hold. Good luck ! Good looking set up there !

 

[casper]

Now THAT's a SRI.

 

[THEGOLDPRO]

i had a cheapo boost controller in my car at first, and it did the same thing, i switched to a turbo xs, and it holds 12psi all day.