Overboost switch and how do I adjust it?

[Asleeper]

Ever since I installed my NPR intercooler and adjusted my boost controller (XBC) to 14-15psi I hit my my fuel cut. I've turned it back a bit now so It doesn't hit the fuel cut anymore. The boost initially spikes to about 16psi and and sometimes hits the fuel cut. Sometimes on a hard run I encounter the same problem. My question is how can I adjust the overboost switch to come on at a higher psi? I thought I remember something about turning a screw in the switch one way makes it engage at a higher psi. If thats so how many turns would be needed to get an extra 2-3lbs. I tried doing a search but that didn't help any.


Andy

84 242ti

[SquareD]

I assume it's the same setup as my car, but I don't know where it's located on a 240. Anyway, the end of it is plugged up, lightly heat the end up with a torch or something, that makes whatever they put in there chalky enough to scrape it out until you get the top of screw completely exposed. Get a nice wide flathead screwdriver and break it loose. IIRC screwing it out ups the threshold.
*Edit* Now that I think about it, it probably needs to be screwed in to up the cutoff, based on how I think it works. Also, although MVP's site says to hacksaw it, I'd try heating it up. I took the first one to a belt sander to expose the screw the first time and there's not much thread inside there. If you heat it up and scrape it out, you don't cut off threads and it'll hold without permanently epoxying the end shut. I heated mine up adjusted it and put a dab of temp. threadlocker on there. That way you can still adjust it later if you want. Also, that site says that the max setting on the OB switch is 16 psi. Does anyone know if you could put a bit stiffer spring in there to up the max setting?

[boostdemon]

MVPvolvo.com covers it quite well in a document on their site.

http://www.mvpvolvo.com/frm_index.cfm?CFID=282577&CFTOKEN=7775234&gear=3P1&tooth=16

"how to advice" | "Adjusting a Factory Volvo Overboost Pressure Switch"

[volvofreak740]

yea dose any body have pics of it so the noobs and i can c were its at

[Asleeper]

Holy thread resurrection batman on my 6 year old thread.

[ikyikthe1st]

my fault i linked to it lol

[mulkeyr]

I think what your actually referring to is the enrichment valve. All that does is add fuel at a set pressure (and yes it's adjustable) the problem your having is the fuel cut off switch. There is a way to disable it though.

[crandandall]

The boost cut switch is under the steering column on 240 turbo's. it looks just like the enrichment switch on the firewall, but it's set at a different pressure. The switch is located in the same general area on 740's as well. I just cut the wires and connected them together, bypassing the pressure switch.