I've never touched my mbc since it was installed and set at 19-20psi. I just drove to the store and spiked at over 25psi!! So, I stopped immediately and started adjusting my Forge MBC. I now have it set at a safe 18psi. I had to turn it alot! My two questions are:

1. I know weather can mess with my mbc, but should it be by that much?? I mean, its 50degrees here in GA.

2. What kind of damage could have been done boosting that high temporarily on my basically stock evo?

 

I found this thread with the same problem:
https://www.evolutionm.net/forums/sh...d.php?t=177154

The thread starter changed to the softer spring to solve the problem. I dont have the softer spring though. Strange that when he turned down his stiffer spring all the way he still spiked 25psi. I wasnt able to do much testing, but after turning many clicks down, it seems to be holding 18psi in 2nd and 3rd. The turbo had been replaced under warranty by the previous owner, so I want to be extra safe.

 

I posted a follow-up on the other thread.

 

If it only happened once, i'm sure your car is fine.

 

Thanks for the follow-up. I'll try mine for a week also. What gear is best to be in to monitor/adjust your boost?

 

This stiif spring is driving me crazy, yesterday I installed it back again and after many runs I set it at 17 clicks (~21.5 PSI). This morning while driving to work I experienced the high spikes again (~25 PSI when giving a quick 50% of gas), so I had to stop and go many times on my way to the office trying to find a good setting, I got it down to 10 clicks holding boost at 20 PSI. After work I'll make a few runs to see if I can get it settle at just below 22 PSI. For some reason the stiff spring is giving me a hard time.

 

I do it in 3rd and 4th gear.

 

That's crazy it's so erratic. Mine has been working ok so far today. It held 20psi in 4th good. Tapers a good bit in lower gears. Still need help holding boost. Can you actually hear the clicks when you turn your mbc? I couldn't. I could barely feel the clicks, if any.

 

The ratchet system is great, but of course is not exactly like the ratchet tools. You can feel the clicks, however you can't hear them. Besides I don't think hearing the clicks is needed, I usually adjust the MBC with my engine running, so I wouldn't be able to hear anything but the engine.

 

Well, I thought this problem was related to the stiff spring only, but I just found out I have the soft spring installed. I was turning up my boost and ended up turning it all the way up. It now peaks at about 19.5 PSI. I now need to contact Forge and hope they will send me the stiff spring because I plan on just a little more boost.

 

I have experienced the high spiking and cannot make good with either spring, even the low boost spring will cause me to spike way too high, when I first installed it, there were no probs, low boost could get me to 19ish, but the high boost spring worked and got me to where I needed to be at 21psi. Seemed to be okay. Very shortly after the weather changed to cooler/colder and even dropping to the low boost spring could not keep the spikes below 25-26psi and fuel cut.

I have since removed my forge and I am using the stock sensor, seems that this will not be a good choice for me in a colder climate with alot of variying climate changes......

Jeller

 

Take it our and get an electronic one. I have never had a problem with mine. besides the occasional error code.

 

I don't think this problem is weather-related. I live in Miami and temp. is now around 80F, but still get crazy spikes above 25 PSI. This does not happen all the time, only when I'm at partial throttle and then punch it, that's when I get the spikes. If I launch my car or punch it after shifting (no partial throttle) boost is OK, just below 22 PSI. This leads me to believe that the stiff spring is getting stuck when partially pressed.

During the last weeks I've seen more people experiencing this symptom with the Forge MBC, maybe replacing the stiff spring with a different spring (not as soft as the other one provided) we could solve the problem, other thing could be using grease with the stiff spring. I want to stick with this MBC, I believe it's great, that's why I'm trying to find a solution instead of using a different boost controller.

 

Funny, my turbo was also replaced under warranty (2 months ago while my car was still stock). I wonder if this might be a common problem with the others? I'm going to check my WG next.

By the way, my UNOS is also giving me problems. I've been posting in that other thread

EDIT: Hey STEEVO, I also don't have a lighter spring and made this a point in my PM to Mike@Forge. He graciously said he would send me one free of charge even though i bought mine used off this site. Maybe he'll do the same for you? Couldn't hurt to try.

 

Trust me, it's not climate related. I don't see how it could be anyway? It's about 30 degrees right now, but back when this was working PERFECTLY, it was around 0 degrees. If it worked fine then, I don't believe cold is the problem. I think it may just be something getting stuck???