As a bit of a recap, up until recently I've been holding 1.1 bar (indicated) on my GT700 car. Backed with Markski's confidence building enthusiasm and direction, I have bought a nice low profile jack and have been under the car to give the waste gate controllers 1 full turn tighter, (making the “tails” longer). This resulted in the indicated boost hold level increasing from 1.1 bar to 1.2 bar. The 1.2 bar is currently attained in the higher RPM range and will hold.

Sharkey suggested getting a MightyVac to test & calibrate the waste gate diaphragms. Todd @ EVO suggested the best way to ensure proper boost levels are being attained is through the use of an after market boost gauge. I plan on getting an additional boost gauge installed in the near term, but want to ensure both turbos are producing the same amount of boost. The external boost gauge will measure the aggregate boost from both turbos.

So I picked up this MightyVac unit today and plan to get under the car to calibrate the turbos tomorrow. I assumed it would be calibrated in LBS of boost. It’s not; as vacuum is measured in kilopascals or inches of mercury and the gauge on the MightyVac shows both.

If I wanted to adjust the actuator bolts to hold 1.3 bar boost before opening, what level of vacuum should the diaphragm hold? Any pointer would be greatly appreciated.

Mike

 

Mike, I was recently told by my EVO dealer that they are coming out with an entire waste gate with the upgraded springs. This is to be as a bolt on so people wont have to mess with the old waste gate and spring. If there is such an animal, I was considering that so I wont have the chance to screw up my waste gates....what do you think?

 

Sounds good, but I'm already in for the $$$. I believe the calibration process is simple.... I just don't know how to do it.

 

Your wastegates may still need to be adjusted when installed on your car... It does not matter whether they were moded or are just new actuators that you install... Moding the wastegates to add new springs is not difficult... Todd at Protomotive already has different wastegates you can install now... He has had them for a while...

Depending on what your trying to achieve I would go with a straight stage IV and not mod anything else... Air box etc.... Just exhaust, DV's ECU and you have K24's I believe.... My car was plenty quick enough like that and I had zero issues... No Blown MAF's, no throttle body shutdowns, etc... just 20K of reliable driving.... Since you track I would not think you need any more power that a stage IV anyway... Your call of course, but my advice would be just read all the threads and see who posts problems and who does not.. Just MHO of course.... Based on my experience....

 

Thanks Gary - but I already have the GT700 with the GT28 turbos & modified waste gates, big TB etc.

When I first got the 640 kit, i believe my wastegates were set set up conservatively. I've upgraded to the 700 kit, which includes fuel pump, rails, injectors etc. The turbos remain the same. HENCE - I need to further pump up the boost, and preferably in a balanced fasion, so both turbos will hold 1.3 bar. I am installing an external boost gauge, but this will only measure aggregate boost. ie. If 1 turbo is boosting 1.2 bar and the other is boosting 1.4 bar, I'm assuming the net reading in the boost gauge will be 1.3 bar. I would prefer to callibrate each turbo so the both hold exactly 1.3 bar.