Any advantages to making the turbine housing WG puck hole larger?

[Bubba]

That's my question. I'm going to have my top end off my motor soon and have continuosly had problems with 3-4 psi of boost spike. Will making the puck hole bigger help in any way?

[nBALLS]

It helps with the elimination of boost creep, and makes for more accurate control of boost. If you have a 3" TU SV, go as big as you can, as their outlet has a HUGE flapper, that's what I did.

If you do that, and still have a spike, make your boost controller vac lines as short as possible. I did a setup for a buddy, that was basically a vac elbow off the back of the intake (90-up Booster fittings have a 1/4 inch barb off of them for the BOV, and 3.3L have two on the intake), the G-Valve, and a less than 2" section of vac line to the WG actuator, and he had ROCK SOLID boost control.

[Bubba]

Don't have a TU swingvalve. I can shorten my boost controller lines though as mine is mounted on the other side of the brake booster (TurboXS unit). I seem to only start noticing spike problems once I adjust up to and above 15psi of boost. I also hae an external spring attached to my wastegate arm for extra tension.

[Chris W]

We don't recommend going as big as possible. That would expose too much exhaust energy against the puck causing it to possibly lift from it's seat. If the WG cannot support the extra pressure you will lose power. Open in small increments only until boost creep control is acheived.

Chris-TU

[nBALLS]

We don't recommend going as big as possible. That would expose too much exhaust energy against the puck causing it to possibly lift from it's seat. If the WG cannot support the extra pressure you will lose power. Open in small increments only until boost creep control is acheived.

Chris-TU

[Dave]

A solution: Ditch the integral wastegate.

Not to argue with nBalls, but I have 8', yes 8 feet, of vacuum line to my boost controller. The trick? A tight spring. Do I lose accuracy, hell yes, but I have sweet control from the comfort of my seat.

Christian perhaps try a different reference source. Try the intake manifold. Response time to the WG can is slower than compressor outlet source. This may help because it will open the flapper slower in comparision to the latter source and engine RPM. Another thing to note, WG's begin to open at 5psi before set pressure.

I truthfully think that the larger turbine housings are not suitable on our applications in aid with an integral wastegate. Here's my theory on it, correct me if I'm wrong... Say if you were to do a paired comparison of a stock T3 and a Turbonetic's T04E 50 trim. You have a .48 A/R housing on the T3 and a .63 A/R housing on the 50.

The pressure at both collectors in each manifold will be the same. Open both pucks at the same given pressure and the gas in the T3 will escape faster because of the restriction in the housing. Gas is still expanding at this point and wants to find the nearest exit, fast. In our 50 trim it will not be as effective to dump the gas through the puck as the turbine housing is less restrictive. The gas will not escape through the WG puck as quickly as opposed to the T3.

It also does not help that our manifold runners have a much further distance to the collector after each stroke (I believe our order is 1,3,4,2?) promoting unequal pulses seen at the collector. I believe this creates the surging seen in so many T04E's.

I may be wrong in some aspects with my theory, but I honestly am very disapointed in this turbo. We should not spend $800 on a turbo and have to install an external spring to make it function properly.

[Bubba]

I must say that I never experienced any problems like this back when I ran a T3 turbo. Going with an external WG is an option for me since I plan to have one of TU's new headers, but then I'll have to have a new down pipe made.

[Bubba]

We don't recommend going as big as possible. That would expose too much exhaust energy against the puck causing it to possibly lift from it's seat. If the WG cannot support the extra pressure you will lose power. Open in small increments only until boost creep control is acheived.

Chris-TU

Thanks for the help on this Chris, maybe I just need to strengthen my external WG spring to achieve what I'm trying to do?