[shiguera]

I am so sorry if this has been been discused. But i have been searching all night long and have not found a definative answer. Which device is better. I know better is a bad question. But what are the pros and cons of each, and what do people around here prefer?

 

[JSkillz314]

Ive heard that dawes is better from a few people. Thats what i use in my car. No problems yet and works great

 

[stromer]

I feel that the MP is more popular. Are they the same price? Being so similar this could be the deciding factor.

 

[SPATL]

The Dawes and MP MBC are made from the same materials. They are both the Gus Mahon insprired Pressure relief valve. The only difference is, the MP unit has a larger outlet elbow. This modification was made to better fit the stock saab hoses to the MBC. The Dawes Device has a .017" outlet and doesn't fit well to the WGA vacuum line without a very tightly wrapped zip tie. The MP MBC uses a 1/4" outlet but does not affect the inside hole of the outlet. So pressure before and after the ball is the same interanally between the two units. Other than that, same device, different price.

Here is the comparison I did on the two units. The smaller outlet is the Dawes, the larger one MP.

 

[stromer]

what is the price difference real quick?

 

[SPATL]

MP=$26

Dawes=$43

 

[shiguera]

So to really compare whats the difference and again which one is better compairing the mp mbc+a and the dawes two stage mbc?

 

[SPATL]

MBC for MBC, they both work the same. One fits better if you are only using the MBC.

You cannot compare a 2 stage MBC to a MBC+A. they are completely different. The 2 stage MBC will give you comtrol of 2 settings. This might be nice so that you can reduce your first gear MBC setting so not to completely lose traction and have a high setting for the higher gears. This design will not deal with the overshoot problems, but has advantages for duel settings over the MBC+A.

The MBC+A effectively deals with overshoots inherant in all ball and spring MBC's and the 2 stage MBC from Dawes will also have this problem. The other pro for the MBC+A is that it allows you to effectively move your boost tap downstream of the IC for longer sustained boost without droop.

So ultimately, a 2 stage MBC+A would be the best of both worlds. But...to do the 2 stage right, would involve more than just throwing on the dawes 2 stage. The ultimate solution would be to locate a magnetic pickup under the shift boot for buttonless switching of the stages. Without the +A, the two stage will still overshoots and you'll have to compensate for that.

 

[shiguera]

From reading post here and over at saablink's forum it seems like the consensus is split 50/50 that the mbc has the potential to be harmfull to the engine. is this true is anyway? The idea of not letting the ecu have control over the boost is kinda scary to me. But the mbc+a seems like a great thing to have installed while in the transition to getting a reflashed ecu.

 

[stromer]

I don't think the risk is all that bad if you're smart. You will most definatly want some sort of upgraded intake. And an exhaust wouldn't hurt either. Make sure you run some higher octane (93 or the highest you can) to get the best performance. bkrell has had his on for I think like 30,000 miles set to just below fuel cut without any problems. This is the same for me. The t25 can certainly handle the 15 psi just fine.

 

[WyldSaabMan]

the stock ECU has fuel maps up to 17psi, since there is a fuel cut at about 15.5 psi you will never reach the stock ecu's fueling limitations. Just be smart about it and use 93 octane gas so there is less chance of detonation.

Also the ECU still has 2 ways to prevent knock, in the case that you put in lower octane gas or some other condition makes the engine run in a way it should not. These 2 other ways are as follows. The ECU can still retard timing as well as add more fuel to prevent knock. The intake mod is not required but will defently open things up a bit and provide some better brething for the engine. Then from there a dp and a exhuast.

but you can safely run the mbc on a completely stock car

 

[Stalker]

As with any performance increase theres always more 'wear and tear' on the engine, but as said before using an mbc is safe (in the sense of running lean) since the stock fuel system maps up to 17psi. It is definitely a smart move to do an intake mod (open cone or the airbox mod) as well as the already mentioned premium fuel as well as a synthetic oil with a quality oil filter. (pretty much just take good care of her and she'll take good care of you ) I ran my mbca with just a cone intake for about a year (15k mi here in atl) and another 6 months with exhaust. My car feels better than the day i bought it (i attribute that to the non-jiffy lube cheapo oil)

Did that caliper ever find its way back to you sp?

 

[SPATL]

Did that caliper ever find its way back to you sp?

Hopefully tonight Hec will bring it with him along with my 6 pt 13mm socket.

BTW: I didn't get your message about the resistor "thingy" until this morning so I won't have it for tonight.

See you at 6:30.

BTW: I have run a MBC(and +A) for over 65K miles on my car. I too believe my car is in better shape than when I first got it. With all the talk about oil sludge, I pulled the valve cover off this past weekend(while I was sulking about being in Atl instead of Carlisle) and was pleasantly surprised at the cleanliness of what I saw. I think there was some old hard depositis from the pervious owner who put the first 48K miles on it. Since I have had my car, synthetic oil has been used and the area looked like it was being cleaned slowly by the use of a full synth. I have pictures of what I mean.