Adjustable waste gate rod, minimum 20 PSI?

[neat]

Last night I made the waste gate rod on the TR in my signature adjustable. Prior to the modification the engine was seeing about 15-16 PSI. I have the rod so long that it slips over the flapper arm with no resistance. In fact, the rod is so long that the boost is taking longer to come on than it used to. I figure the flapper isn't being held 100% closed so some exhaust is sneaking by it and slowing the spool time just a hair.

Even with the rod that long, I am still seeing 20 PSI instead of the 15 I was seeing before I modded the rod. Is it possible that I somehow damaged the actuator when I modified it? I was pressing the rod into the actuator pretty hard when I ran the die over it, could that have done something to the actuator? What about the rod turning inside the actuator?

Seeing that 20 PSI seems to be the minimum boost I can run at the moment, am I risking the engine/head gasket at that boost level with no tune, and no knock gauge? Right now the car is 100% stock other than the actuator rod mod. I have a tank full of home made race gas that should be about 98 octane if the formula on .org is correct.

The car pulls all the way to the shift point super smooth at this boost level, and does not audibly knock, miss, sputter, or anything. However, I still fear the knock. I am working on getting an audible knock gauge, but it'll be a week or so before that happens. I'd love to take the car to the track and embarrass a buddy of mine with a 2004 Lightning this weekend though. If you guys don't think it's safe though, I will hold off.

Thoughts/advice?

 

[VadersV6]

You probably tore the diaphragm while doing that, and now its leaking off air and not opening the puck. You probably twisted the hell out of the rubber till it ripped. You need to unscrew the rod and stick it in a vice before machining it.

 

[neat]

From what I could see the rod does not unscrew out of the actuator. Am I interpreting you correctly that the rod simply screws out of the actuator, so you could remove the rod without removing the actuator?

Thanks!

EDIT: If that is what I have done, is there a way to disassemble the actuator and repair/replace the diaphram?

What about the 20 PSI on the stock set-up with good gas?

 

[gmncop]

The Longer The Rod The Lower The Boost , The Shorter The Rod The More Boost You Should See.if The Rod Is All The Way Out And Your Seeing 20#'s I Would Be Careful.

 

[Ormand]

Vader, that's a good point about the wastegate diaphragm. I bet lots of us have a leaky diaphragm, and don't know it. Should be part of the "spring cleaning" to check the thing with a MityVac or equal. Many of us (not most, but many :smile: ) know enough to check the hoses for leaks, splits, etc, but how many check the actuator?

 

[neat]

Vader, that's a good point about the wastegate diaphragm. I bet lots of us have a leaky diaphragm, and don't know it. Should be part of the "spring cleaning" to check the thing with a MityVac or equal. Many of us (not most, but many :smile: ) know enough to check the hoses for leaks, splits, etc, but how many check the actuator?

That's a good idea. I have a mighty vac, I'll check the pressure that it takes to open the actuator with that.

 

[neat]

You probably tore the diaphragm while doing that, and now its leaking off air and not opening the puck. You probably twisted the hell out of the rubber till it ripped. You need to unscrew the rod and stick it in a vice before machining it.

After looking at my wastegate rod, you can't unscrew it from the actuator. What are you talking about?

 

[rodman99999]

I've never seen an actuator rod unscrew. How do you go about that? When I cut and threaded the rod on my '85, I simply clamped the rod in the vise at an angle. Why even try to remove it?

 

[neat]

*sigh*

The problem was not a faulty component, damaged diaphram, or anything else. It was operator idiocy. When I reinstalled the waste gate actuator I forgot to hook up the vaccum line to it. The actuator was never even seeing boost. It's a miracle I did't blow up the engine or something.

With the vacuum line in place, and the rod as loose as I have it, I am down to 12 PSI.

Looks like I'll make the track this weekend afterall. Wish me luck against the Lightning. 12.9 is his best VS my 14.1. With some more boost than stock, and a better launch I think I've got a fighting chance.