I heard that the wastegate spring is set at 15psi, is there any way I can change teh spring because I want to lower the boost so that it only runs 12-13psi. Anyone know how to go about this?

Is 15psi too high on 91 octane gas? I don't want to blow my motor, i'm just looking to build a safe/ reliable car.

 

i need to know this too. in a previous post chuck said to cut the spring in the wastegate, since no other one is available. chuck, maxcooper plz chime in.

 

The wastegate spring is indeed a 1 bar spring. 14.7 psi. I trimmed the spring down... a little at a time until I could get some control of the boost.

Although I am concerned that I might have cut too much and am having a constant wastegate dump.

 

Is this true with a separate waste gate controller like the HKS EVC? I thought the vacuum lines from the electronic valve controller will open the waste gate earlier if desired by pulling vacuum on the wg, making the wg open at a setpoint lower then the spring by itself.

 

the car we put that turbo on only ran 12-13 psi with the stock waste gate spring. it did vary with the muffler we used though (the n1 was too loud)

mike

 

I can set mine at 12psi, and thats with a straight exhaust.

 

I called apex'i today and they said the wastegate spring is only for 10psi. I don't know why everyone else I've talked to says it's 1 bar, but if other people can boost less, than I guess I should be fine with only 12-13 psi...

 

I called A'PEXi also and they told me it was adjustable from 1 to 14LBS. prox. by the bottom bolt. "SO WHO KNOWS" they sure don't

 

OH BTW I replaced mine with a TIAL.

 

Which tial wastegate? Does it bolt right onto the exhaust manifold? And also is there any particular reason you would do so?

 

Well,

I went through this flail for about a month... including contacting APEXi in Japan. Of course this was 18 months ago so they might have developed a new spring for 10 psi.

I kept seeing 1 bar + but I run a completely open exhaust.

 

RX6 - The wastegate sucks in my opinion. A friend blew his engine when it stuck open. I put a Tial 46mm on mine. To do this use a 1-1/2" to 1-1/4" 304ss SCH10 or 40 pipe reducer and a 1-1/4" 45 degree elbow cut to about 30 degrees. For the connection to the down pipe use 1-1/2" 304ss tubing. Purchase 2 with 90 degree bends and cut 1 of the 90s in half = (2) 45 degree bends then Y it into the down pipe as far down as possible before the mid pipe. Lastly, weld a support to the tube to help support the weight and vibrations of the wastegate. Very basic. When you look at it you will understand. If you do all the cutting and pre-fab first, it will save you a lot of money. I started on mine at midnight on a Saturday and finished by around 3:30. I am a little warped because I should have been out getting FCKED. After you are done, take it to a competent TIG welder. Make sure that he purges all the oxygen out of the air surrounding the welds inside and out. If this is done you will have minimum melt through (the inside) and a very sound and beautiful weld. Welding will cost you around $60 to $120 depending on the person.

If you keep the A'PEXI wastegate (I hope not) just buy 2" 304ss tubing and plumb it as previously stated. Should cost between $40 and $80.

Another option that I did not check out is an HKS which is suppose to be an almost direct bolt on. I saw this posted don't know where do a search. Hope this helps.

I copied this from a previos post I made. I also did a search and it was Max Cooper that stated the HKS is almost a direct bolt up. Very KEWL because that would have made my life alitle easier. FYO the 45 degree elbow is cut to around 20 degrees rough numbers.

Oh and I was wrong about what A'PEXi told me they said between 1 and 17LBS.

 

I guess I should have read my original post before I posted it and I should have read it before I posted it again.

It should say when the wastegate stuck closed.