SaabCentral Forums banner
1 - 16 of 16 Posts

·
Registered
Joined
·
74 Posts
Discussion Starter · #1 ·
ok just got an MBC from the wonderful ebay:D from wat i read on here i wanna connect the hose in between the Wastgate and Manifold? or between the apc and wastegate? little confused on where to connect it so anyhelp with that and then secondly the boost gauge i can just T off the vacuum line behind the dash for the old boost gauge correct? anyhelp with any of these 2 questions would be greatly appreciated:cheesy: thanks
 

·
Registered
Joined
·
38 Posts
Scaab89 said:
and then secondly the boost gauge i can just T off the vacuum line behind the dash for the old boost gauge correct?
Yes, you can.

Scaab89 said:
from wat i read on here i wanna connect the hose in between the Wastgate and Manifold? or between the apc and wastegate?
If u use MBC, your APC won't work. But if that is not the issue, put it between wastegate and place where you take the pressure signal. That is originally compressor outlet, but you can take it anywhere before throttle plate
 

·
Registered
Joined
·
74 Posts
Discussion Starter · #5 ·
i also got a air/fuel ratio gauge so i was wondering if anybody could give me a fairly detailed write up on how to and where to hook that up it wuld be greatly appreciated:D
 

·
Registered
Joined
·
2,059 Posts
Scaab89 said:
i also got a air/fuel ratio gauge so i was wondering if anybody could give me a fairly detailed write up on how to and where to hook that up it wuld be greatly appreciated:D

The gauge should come with directions.


If it does not, look at the manufactures website.
 

·
Registered
Joined
·
1,478 Posts
MBC with APC

okay i have tried doing this too, i bought a powerup MBC and fitted it inline with the pressure transdcer (sensor) and set a 4psi bleed off but the problem i had was very unstable boost after about 10psi due to the APC lagging behind the pressure increase or rise in boost, creating a boost "spike". then as combustion temperatures rise rapidly boost is cut from knocking and you're back to stock boost. if you want to get higher max boost pressures, mod your APC. if done properly you can get from 12 - 16psi max boost.
 

·
Registered
Joined
·
74 Posts
Discussion Starter · #8 ·
YAY!! my gauges and boost controller arrived today i'll fit them after christmas break seeing as how my car is sitting in the shop at school and my a pillar gauge mounts haven't arrived yet:cry: will get pictures after it's all mounted:cheesy:
 

·
Registered
Joined
·
5,779 Posts
You can hook it up inline with the W hose between the APC solenoid and the wastegate to raise base boost, and still have knock protection at boost levels above the new base boost.

That being said, if you don't know how to hook up a MBC, you probably should not be using one.

APC good, knock bad. :D
 

·
Registered
Joined
·
181 Posts
TheRedBaron said:
APC good, knock bad. :D
Never a truer word said - I had my 900 on a rolling road recently and we did a couple of runs in normal road trim and an experimental run with the APC disconnected and the wastegate line throttled (as if there was an MBC fitted). It made an extra 15 BHP but I could hear it knocking even through my ear defenders - it's not a nice noise at all.

I've got a theory that there are more 900s about today than any other turbo car of the same vintage solely because of APC..
 

·
Registered
Joined
·
3,691 Posts
nuclear_jimbo said:
Never a truer word said - I had my 900 on a rolling road recently and we did a couple of runs in normal road trim and an experimental run with the APC disconnected and the wastegate line throttled (as if there was an MBC fitted). It made an extra 15 BHP but I could hear it knocking even through my ear defenders - it's not a nice noise at all.

I've got a theory that there are more 900s about today than any other turbo car of the same vintage solely because of APC..
Possibly. My 81 turbo has no APC (way it was designed) and I can hear when it knocks so I just back off the throttle, but I'm trying out a few things to counter the knock such as adding an intercooler (most 8V turbo's didn't have intercoolers), improving the engine's cooling system so there's less heat-soak into all the metal parts around the engine bay, etc.

I might even try water-injection but I'll probably try out a fan on the intercooler itself if I go with a T16 one, or I'll opt for an FMIC instead now I've removed all the air-con gear.

Craig.
 

·
Registered
Joined
·
13 Posts
Scaab89 said:
YAY!! my gauges and boost controller arrived today i'll fit them after christmas break seeing as how my car is sitting in the shop at school and my a pillar gauge mounts haven't arrived yet:cry: will get pictures after it's all mounted:cheesy:
Got those piller gauge mounted yet, Im looking at getting one from genuian saab but would like to see a pic of one mounted first.
 

·
Registered
Joined
·
74 Posts
Discussion Starter · #13 ·
actually i couldn't use the pillar gauges i had to get a new dash mount caue the pillar on my 87 is too thin and to upright made for hard reading so i opted for a dash cluster pics coming sometime next week prolly:cheesy:
 

·
Registered
Joined
·
18 Posts
Good to see another Wisconsinite on the boards! I'm from Milwaukee, got an '87 too! But mine's an S model, and should be boosting sometime in the near future.

Good luck with the project. Be sure to post some pictures, too!
 

·
Registered
Joined
·
74 Posts
Discussion Starter · #16 ·
't that one mine was from the evilbay and yes nice to see another wisconsinite on board also:cheesy: where in milwaukee r u located?
 
1 - 16 of 16 Posts
Top