Engine: 70 T5: Manual Boost Controller and Boost Gauge Help Needed

[FatLadZ]

I have a manual boost controller and i have a boost gauge spare.
IUve seen alot of posts mentioning these and ive been searching around but cant find the info i need to tweak up my boost pressure
My car is a volvo s70 T5 1998 with 140k miles
Can anyone explain what and where i need to alter and adjust things and to what pressures
I know i need to adjust the actuator but i just dont know if i need to do anything else

Don't mess with the actuator rod. The MBC goes in the line between the electronic solenoid (on the back of the airbox) and the wastegate actuator. It's a simple spring loaded valve that stops air getting through to open the wastegate until you have reached your set boost. The amount of boost you get depends on how tightly you load the spring by screwing the adjuster in.

Sort the gauge first, then fit your MBC. Make sure you use good hose clips - tiewraps won't do. The hose you need to fit it in will have yellow bands at the end. Start with the adjuster wound right out and experiment, winding it in a bit at a time, until you have reached your desired boost pressure.

The standard boost pressure as allowed by the electronic valve is, I think, about 14-15psi (0.9-1.0 bar), so if you exceed this, it's at your own risk!

[PNuT]

Originally Posted by stuartsharp

Don't mess with the actuator rod. The MBC goes in the line between the electronic solenoid (on the back of the airbox) and the wastegate actuator.

i have bypassed the Boost control solinoid completely

You can do that, but it won't make any difference unless you're wanting to limit the boost to below normal levels.

By leaving the ECU solenoid in place and adding a MBC, you can improve the turbo response slightly without exceeding the standard boost pressure. Set the MBC to the same pressure as standard, and it will ensure that the ECU cannot start opening the wastegate until you're at maximum boost.

Of course, you can still set it for increased boost if you want, and the ECU solenoid cannot possibly interfere.

[FatLadZ]

dont suppose there are any guides on doing this ?
thanks for your lovely replies

[FatLadZ]

thatll be a no then?

[irf]

first thing would be to find out wether or not you have the etm. thats the electronic throttle, if you have this then fitting the mbc is a waste of time as the car wont allow you to go above standard boost unless the car is remapped.
if you have a throttle cable then you need to fit the boost gauge. i used THIS GUIDE it's not brilliant but a few searches will help.

with the mbc have a look at the diagram below.



you can see the turbo and the boost control solenoid(bcs). all you do is, on the bcs side, disconnect the blue pipe and block it off. with the yellow and green pipes, take them off the bcs and connect them together with your mbc. voila!!
if adjusting the mbc has no effect on boost you may have the mbc connected the wrong way.

[aaronturbo]

To say if you have an electronic throttle body a mbc won't work is incorrect.

The mbc works just fine on my c70 2.0t.

In parallel you will not see an increase in boost just snapper delivery.

After the tcv, on the yellow line before the waste gate it works as you expect and will increase boost however I found that the boost spikes high.

On its own with the tcv plugged in bypassed to no throw a code it works best. I have my lpt at 11psi zero problems. Much more than that and I hit boost cut/fuel cut.

If anyone needs any help with this let me know.

I advise a simple afr gauge, dosent need to be wide band, as WOT is really what matters.

Just so you don't over do it, any signs of ping/detonation the motor pulling timeing dial it back abit. Use the best fuel you can get hold of,

Boost gauge is a must and this can't be attempted without one.

I use Vpower.

[aaronturbo]

i will also post a follow up with my findings surrounding me7 cars and boost control.

because most of what you will read regarding mbc and ebc is false and comes from people with deep pockets for a remap.

[Shinsplintz 101]

.....now that's what you a thread resurrection.....over 13 years in the darkness...then BOOM. Dusted off & dragged out into the cold light of day.

Shame it's a thread about MBCs vs ME7 ECUs.

My advice....for what its worth.....don't bother. In the last decade or so general swedish tuning wisdom dictates that gains are so marginal buggering about trying to trick the ME7 ECU that you might as well have left it stock.

Better off buying an pre-ME7 car and tuning that. The ME 4.3 or better 4.4 is much easier to cheat, getting considerable gains from mechanical intervention.

Anyway. Don't feel obliged to take my word for it. God loves a trier😆