I took my car to get dyno'ed the other day, I have a utec with a vf34 and other mods. well the problem is when he went to tune it he noticed that my car's boost wouldn't go up like it should. It goes up to about 7 levels off wile the wastegate is open and then goes up to maybe 10. The boost setting on the ecu are set at 18 but my car never gets to 18 what can the problem be? If you need more info let me know. thanks.

 

your problem is either you are running the UTEC w/o the ABC valve OR your turbo hoses are missing the restrictor 'pill'. Either will cause maximum boost to be low. Any good tuner would have known this.

 

So if i buy a boost controller will that fix the abc valve problem? thanks

 

if you get a seperate boost controller, you can ignore the valve. take it out. i dont think youll have to worry about the restrictor pill either.

 

That is correct. BUT there is no need to buy an expensive EBC or MBC. You can pickup a GM (Syclone) Boost control solenoid for ~$15 new. I've been running one for almost 2yrs & love it. I've tuned several others with them as well. ALL respond much better than stock & hold boost much much better.

 

wow. GM Cyclone? i havent heard of those in years. beefed up blazer. whered you get yours? online?

 

Yup online, there's a link on NASIOC with all the part numbers. I don't have them in front of me, I'm at work.

The BCS cost ~$12 & the harness another $15.

NOTE: IT WILL REQUIRE YOUR BOOST, WASTEGATE, & TURBO DYNAMICS TABLES TO BE RETUNED. DO NOT USE IT IF YOU CANNOT GET A CUSTOM TUNE.

 

^^^good info. ive got a piggyback, so ill be ok.

 

i had the same problem... mike at gst fixed my problem... mine was the "pill" in the vacuum line handt been reinstalled

 

True, these solenoids give better control once re-tuned. But, the MBC is consistent all the time and always delivers better boost response once tuned for an MBC.

 

Agreed, I've ran both the GM BCS & an MBC at different times. The best part of running an BCS is the temperature compensation that the ECU takes care of, as well as elevation changes.

Actually you can run both an MBC & a GM BCS at the same time. You set the 100% throttle postion column in the ECU or UTEC to 100% WGD. The GM BCS will work at all part throttle situations & the MBC takes car of MAX boost situations. This only works in Internal wastegates.

 

i wouldnt say the MBC is consistant all the time. ive noticed 2-5 psi difference when its really cold outside vs a mild day.