Modifying the Wastegate actuator rod...

[MadeInJapan]

Will work on any turbo...just won't get as much boost w/ the low pressure turbo.

[IVIUSTANG]

First off, pardon my obscure referencing to turbo parts, I don't know most of their specific names.

I had a problem doing this to my 1998 S70 T5, the piece that I was supposed to turn was very seized and as a result I couldn't budge it. Instead the whole shaft turned(I tried holding it) Is it harmful if the whole shaft turns instead of just the piece on the end? I also noticed at the end I was supposed to turn that the "valve" was fully engaged and couldn't go any further, I assume shortening the rod makes adjustments on the other end(thereby making that valve take longer to open etc) am I correct? I also noted that there was no cotter pin over the adjustable piece, it seems to me it should have one but I couldn't find a hole?

Thanks,

- Jesse

[rbodor3]

turning the entire thing isn't really that big of an issue. yes it should have a cotter pin thru the WG valve and the end of the WG actuator arm.

A common mistake is the misconception that boost = power which is not always true.

Even if you raise boost pressure your power can stay the same. By raising boost with a stock car (specifically, the exhaust) you're really going to just be creating more backpressure, heat, backfire, even reverse the direction of the turbocharger compressor with too much backpressure (which will of course destroy it), early detonation, and high peak boost with low drop off. Even if you do this correctly and build boost earlier, the ECU will recognize this and retard timing if stock. So basically by building boost earlier you don't do much of anything unless you're trying to build it up to come on sooner.

By changing the WG actuator you're not increasing your boost, you're just deciding when you want it to come on. By tightening it you have it come on earlier - which with the completely stock exhaust system can and has lead to bent rods and detonation.

If you aren't sure what the names of the turbo parts are, you shouldn't do this without a boost gauge. In fact, don't do this without a boost gauge ever unless you know what you're doing.

[xb corp]

[quote="rbodor3"]A common mistake is the misconception that boost = power which is not always true.[quote]

i agree with rbodor3 very much on this.
friend of mine, tweeked his stock TD04-15G (many turns on the actuator) and installed an MBC, hoping to achieve 1.1bar.

yes he got 1.1bar, but mine, even at only 0.9bar, it gave me 286hp.
his only 208hp....

the main difference is the turbo & set up. i am running on Nissan Skyline ballbearing....

[IVIUSTANG]

Yes, I have an aftermarket boost gauge set up. like I said, I am mechanical but not experienced with turbos hence not knowing the names of all the parts. I attribute my 15 PSI max to my methanol injection system, it really seems to do a nice job overall. I have decided against this mod as I am happy with my car the way it is. But good luck to all!

- Jesse

[Reys]

I've read posts regarding boost and the waste-gate arm shortening technique which we understand as a means to increase the timing when boost starts to build, so this procedure did not help with the current low boost levels in my 97 t5, my understanding after much diagnosing of each individual part is that the spring inside the actuator must have weakened and in turn opens the waste-gate prematurely, causing low boost pressure (about 1/4 of the white bar at wot). I've purchased a 7.25 psi spring and am going to attempt in replacing the current one. Has anybody else done this, is its straightforward or are there some hidden steps involved. I assume it's take apart open up and swap. Also has anybody else done this swap on their stock system, and what kind of yields occurred?

,Rey

[rbodor3]

It's very difficult to replace the stock spring on the WG actuator. Additionally, they last very long. I imagine though that your car has seen it's fair share of miles (being a '97) and probably does have a slightly weakened WG actuator spring.

Trying to replace the WG actuator spring is very difficult, because the WG is sealed thru a bent flange. You will more likely then not damage it trying to open it, and if you were able to open it, would be very difficult to seal up properly without any leaks.

A better idea would be to purchase a Garrett, or another after market WG actuator. I bought my Garrett (which has an 8psi spring) for $120. Expensive, but well worth it if you can handle.

[Reys]

rbodor3, haha I agree with you. I did take apart the actuator and could not get the thing sealed back together for the life of me. I did end up purchasing an actuator online with a spring pressure that should crack at 7 and fully open at 10psi. hopefully it should do the trick

[rbodor3]

You'll be really happy with the 7psi actuator, especially if you're running a bigger turbo.

For all the others considering this, you can get a custom-made Forge WG actuator spec'd with whatever spring strength you want for about $150. The best part is it is sealed with I believe a gasket and some hex's, which means you can change out the spring if it goes bad, or if you want to go stronger/weaker

[Steve Wiener]

the spring in the stock wast gate is too soft to get any kind of substantial boost plus there is a boost control solinoid before the actuator.u mught turn it up and see a slight increase.i turned mine up all the way,and also installed a manuel control valve bi passing the solenoid and still only had 14psi.i modified a stock one to adj my boost to 15 psi and found very little movement in acuator.right now im running with my wast gate completly closed and i get 17 pounds of boost.my 98 v70 t-5 5 speed pulls nice and is quite the tire burner.