'05 max boost question

[Topless in Cali]

I recently installed a boost guage in my 05 convert (stock PCM) and put in a TCC wga. I'm using the larger outlet on the bottom of the turbo to activate it. No boost controller, just the line straight to the wga. It holds boost at 13psi, but the PCM is faltering (pulling timing) at about 12psi?? I know many out there are boosting 13-15psi with the stock 04 PCM. Anyone know if DC lowered the max stock boost for '05? All my silinoids are seeing pressure, but the ends of wga and bov/sv lines are capped and I'm using the TB line to pull the bov.

[santacruzer]

You should check out the SRT forums for more information. Also, with a stock PCM, you probably need to disconnect and cap off the TIP sensor, the vacuum hose that goes into the upper charge pipe from the intercooler to the turbo.

[Topless in Cali]

I've been doing research but some of things I found like the TIP sensor mod, don't work on my car. Capping that TIP makes the car pull timing at like 8 psi! The stock PCM has to see pressure from all the silinoids to work properly, I think S1 doesn't, but for 05, I'm not really sure. I did however reconnect the return line from the surge valve silinoid and that helped. It won't start to falter now unless I hold 13psi past around 4800-5000rpm's. If I can keep it at 12psi with throttle input, It really screams. It's just that the wga won't open till 13psi so trying to pull it to redline with WOT still makes the PCM scream. Once S1 is out, I'll install my boost controller and run it at 18psi, then we're talkin....

[Alini]

I'm running an 05 GT 4 door, I have 10 PSI in first gear and 13 PSI in all others. Everything I have read says thats the right stock numbers. I have heard though that you cant play with boost unless you have Stage 1 installed otherwise the computer will keep adjusting to stock numbers.
Did you adjust the WGA at all?? if you just bolted in a replacement WGA without any adjustment to spring tension inside then you didnt improve anything.

[Topless in Cali]

The wastegate actuator is from turbochargers.com, company out of Tx that does work on srt-4's and other cars. It has a much stronger spring in it and can hold boost up to 20psi steady. It can be activated by as little as 13psi though. The problem is that using the standard pressure line from the back of the turbo makes it pull at about 13.5-14psi. A little to high which makes the computer start to drag timing, you can feel it in the car as a slight bump in the acceleration under WOT. And if you use the line from the underside of the turbo it makes the stock BOV open and boost goes shooting out. you can also run a straight line from the throttle body line to the BOV to equalize pressure under boost and keep it closed, but the problem with that is under vaccum the BOV opens as it is pulled by vaccum. To correct this blow off under vaccum, I had to order a Forge motorsports BOV with the interchangeable springs, which I will need anyway if I want to run 18-20psi under S1. So I bought a Mopar unit that I really didn't need, but live and learn. Now I read up before I buy stuff to make sure I don't have to rebuy the same thing just better. Now I am in the process of researching boost controllers which will be needed to run the higher boost. Probably a Greddy profec b, 2 stage so I can run 15 most of time and 18-20 WOT. Of course, this all depends on wether or not they will ever release stage 1 for the 05. I'm getting a bad feeling about it....[:0]