msbc with 3 soliniods

[tom j]

I have a used unit that I received withe the car uninstalled, but it came with 3 soliniods two of which are plumbed in parallel. Would the parallel ones be the increase side or the decrease side?

 

[Louie L.]

Unless this is a new modification of some sort, it should have only one increase and one decrease.

 

[tom j]

I thought I read some place that this done when boost fluctuating is an issue, but still not sure on what goes where.

 

[tom j]

ttt

 

[DR BOOST]

is boost fluctuating an issue Tom?

 

[tom j]

I'm just installing it now, but thats how it came being hard plumbed already. Just wondering why the 3 soleniods vs 2. All i can think of is that those 2 would need half the duty cycle and work less.

 

[murphster]

It would probably be an extra decrease solenoid. When hooked up in manifold mode, a lot of people get an overshoot of boost before it bleeds down to the desired boost. I've heard that an extra decrease solenoid can help. Its recommended to hook up the controller in wastegate mode to try and correct the boost spike. However, you may have slightly different boost levels compared to the manifold when using wastegate mode.

I'll post up my experiences soon as I hooked up an MSBC controller last year in manifold mode, then went to Co2 control, and will be changing it over to wastegate mode this week. I get an overshoot on boost when staging with the Co2 right now. It does come down, but takes too long when staging to cut a good light.

 

[tom j]

It would probably be an extra decrease solenoid. When hooked up in manifold mode, a lot of people get an overshoot of boost before it bleeds down to the desired boost. I've heard that an extra decrease solenoid can help. Its recommended to hook up the controller in wastegate mode to try and correct the boost spike. However, you may have slightly different boost levels compared to the manifold when using wastegate mode.

I'll post up my experiences soon as I hooked up an MSBC controller last year in manifold mode, then went to Co2 control, and will be changing it over to wastegate mode this week. I get an overshoot on boost when staging with the Co2 right now. It does come down, but takes too long when staging to cut a good light.

That's kinda what I figure, but I couldn't find the post I thought I read it in awhile back. Since you use the msbc how does it work when using the 2step operation (normal street driving) does it just use one stage. Also I plan on using the time boost stages. What triggers that? I understand that ounce you come out of launch mode it starts a stage1. How does it know your using time instead of shift input. The write up is kinda so so.

 

[murphster]

During normal street driving, the controller just stays in stage 1. After triggering the launch mode, the controller will automatically go into the timed stages after you release the launch trigger. It defaults to timed stages if you don't have the shift triggers hooked up.

I like the directions here a little better than the ones that came with my unit:
http://www.exileturbo.com/images/pdf/msbcmanual_Exile_revA.pdf

If you look at the diagrams, in manifold mode the boost sensor hooks up to manifold pressure (just like a boost gauge). In wastegate mode the boost sensor ties into the wastegate. In wastegate mode you directly adjust the pressure to the wastegate rather than relying on what the measured boost is at the manifold. As it explains in the instruction manual I linked to, in wastegate mode you'll have to figure out what pressure to apply at the wastegate to get the desired boost at the manifold. This will depend on what spring you are using, what IC, etc.

 

[tom j]

Thanks!

 

[Louie L.]

I was able to get rid of the spike on mine by going to wastegate mode.