legacycentral bbs

Due to lack of time on my part, other crap, and not sure about a final engine management solution I was thinking about just using a MBC to see how the car reacts to more boost, and wanted to get some thoughts.

Should I even bother?

Yeah...that's all I use...and if I remember correctly you have a TD05 and an AWIC?!?

So, go to home depot and get some parts to make a bleeder valve, and then crank her up to 12 psi or so and you should have tons o' fun

Josh, i've been running the turboxs dual stage mbc for about a year now, first at 8/11 psi and now at 10/15 psi.

haven't had any problems, and flipping the little toggle in the car is fun

in all seriousness, being able to turn the boost down if you think you're having a problem, on the fly, without having to stop, pop the hood and adjust is really great for piece of mind.

and gas economy, if you're so inclined...
lol, i sometimes wonder if the "on" light will burnout

you should be able to find a used one for about $100-150cdn (don't know what your budget is like) however i do know they cost more then double that new.

Thanks for the comments guys.

I've got a single stage TurboXs that came in the car. Works great. Only downside is what bane said about having to stop, pop, and adjust.

Do you find yourself adjusting it frequently?

I know the question was directed at psychoreo, but i thought i'd chime in...

The only time i ever adjusted mine was when i set it up. set it to what i thought was right... hit 7psi, found it no different then stock, so i upped it to 9. it was like that until the bigger turbo and intercooler went on.

once you get it set... not much point in changing it unless something goes wrong.

you know the limits of your engine setup... either you set it for power or you set it for economy. it's a small hex key, easy to add to a keychain that splits in two, full turn for 2 psi.

10 is nice, gets good mileage, still accelerates good
15 is fantastic, mileage is not quite as good, but accelerates like a bat out of hell, but you should only do it if your running an intercooler.

once the injectors and tune are done, i plan on setting to 10 and 20 psi (i plan on a tune for each boost setting, and keying it to the toggle switch)

i expect the 20 will so dramatic, that i may not neccessarily want to use it all the time.


if i was stuck with a single setting i'd probably just leave it on high, and learn to moderate the gas consumption with some weaker pedal action.

Same hers, only really had to adjust it when i first got it. It was set at 5 (boring) so i turned it up. Accidently set it to 15 (no instructions and a little trigger happy + no FCD) so needless to say i turned it back down. It's running around 9.5~10 now and is fine.

Cool, I'll do some looking around at the different MBC's.

I'm glad you brought this up, josh. see, I been browsing my catalogs at work, but I haven't quite been able to figure out which parts are the ones I need? what is an mbc constrcted of? I know its really just basic pneumatic parts. . . right?

It's a ball and spring basically....but something you buy will probably function better then something you put together with fittings from home depot.

woah... sorry forgot that little tidbit.... you'll definitely need an fcd of some sort if you're pushing 12psi... if you spike, it'll cutout

i'm running a pneumatic bleeder, cost me about $20

pneumatic bleeder, exactly what I was talking about.

what's our npt size? james, any related stuff?

... lol, much to my embarrassment, i have no idea what npt size means...sorry...

Nuwan made them a while back and still had a couple kicking around when i picked it up from him...

literally a little vent that opens at 12 psi... with barbed ends on either side. put this in line between the manifold and the pressure exchange solenoid...

pretty much where the letter "B" is, in Vikash's vacuum hose drawing.

http://www.graphics.cornell.edu/~v/vacu ... vacuum.png

There should be a hose that runs by the top of the air filter box, that get's twist tied in place next to the maf... i cut this and inserted the bleeder there.

Installed this at the same time as the mbc, and have never had it cut out.

hope that helps.

I'll try and find out if he still has the part #'s and the instructions to make them

npt refers to the size of the 'barbed ends' and what hose goes with them.

I think if I can manage it, I'll try and make myself an MBC and maybe look into a set of ss brake lines as well. . . I figure most of these are semi-generic hydraulic/pneumatic parts with names and slight spec changes.

NPT= National Pipe Thread...and refers to the thread pitch on the fitting...not the hose size Tristan

Thanks Nick. You wanna work at teh Grainger, too?

Continuing conversation (MBC comparison) here

http://bbs.legacycentral.org/viewtopic.php?t=29324