Very true...although you never know. Gremlins get into the most absurd places...

 

I was going to take the car up to get the boost tube checked out and have the gasket placement issue solved when it started snowing....hard. Guess this is gonna have to sit for a day or two until the roads are dry.

 

Well..... the answer is an obvious one no one thought of. The evolution wastegate is only good for, the TN site says. for 400+ flywheel horespower. I spoke to friend @ Central Florida Turbo today who is a Turbonetics dealer and builds some pretty sick cars and he told me that the gate is already flowing 100% and should be replaced with one of the larger wastegates like the Nexgen, or the Race Gate. If the gate canlt flow enough it can't relieve enough pressure and continues to build boost.

Respect
JET

 

As I said in your thread....

 

Per the TN website under description EVO wastegate.

The new Turbonetics Evolution redefines performance for external mounted boost control. Utilizing the latest technology in flow design and materials, the Evolution features an investment cast 304 stainless body designed with computer flow analysis. "Nitronic 60" stainless steel one-piece valve, and polished aluminum billet cap. Nearly 25% smaller than the Deltagate, it is sized to fit into the tightest turbo systems. Fitted with a rolling type diaphragm and floating valve seat, it is equipped to comfortably handle 400+ HP and out flows the competition by almost 20%

Those numbers are FLYWHEEL HP. Not wheel.

Respect
JET

 

This double posting is getting silly And once again as posted in your thread.

 

Interesting thought, but I have a hard time believing that's the issue considering that Turbonetics advertises the power of this kit to be 385 *WHP* (see the banner ad at the top of this page) and there isn't a Z around that loses less than 15 HP through the drivetrain. If what you're saying is true, then the Evolution would be too small for installation on a stock install with stock exhaust, right?

And now for the big questions:

1. If you're right, what larger wastegate will fit in the tight space we're left with, and will it mate up to the existing flange.

2. If you're right, is it JUST the gate that's undersized, or is it the opening on the exhaust pipe, the dump tube, and the opening on the downpipe as well. If all of these are too small, then a whole new recirculation system is in order. Venting to atmosphere may be the only choice we have, IF what you're saying is true.

 

But Kelly if it is true, then all of us would be having similiar boost issues.

 

Not true.... if you want more boost than the 8-9PSI the kit is designed to deliver then you will need to use less of the waste gates petential ie.... divert less exhaust from entering the turbo to create higher boost than someone looking to creat 8lbs of boost. The 8lbs of boost requires bypassing more exhaust through the WG. Hence maxing out the flow of the wg at lower boost settings.

Respect
JET

 

You know JET, when my kit was first installed the line was connect to the wrong port on the BOV... Causing me to only get 5psi, consistantly and steady. Then I figured out the top port, switched it... 8psi steady, and I know that I am not the only one.

You are right, wastegate needs to open so you don't go over 8psi. But with the 9lb spring that is provided clearly it works. Since it did for the rest of us, or so far.

Except for the two of you, hence why we are all stumped. My point only is that IMO it isn't the Evolution wastegate since it works just fine for the rest of us... I would better see it from your point of view if more of us were also effected in such a strange way.

 

Yep, that's exactly my point. You and I are on the same page....but with as much of a pain in the *** as this has been, I'm willing to accept that anything is a possibility.

 

Trus me mang, I know what you mean... When I was having all my problems, I couldn't even sleep thinking of why or how stuff was working wrong.

I am sorry for you and JET having this much trouble

 

These may be the common factors involved here.

Relatively low boost demand.... 8-9PSI requiring the wg to operate near max potential. At least lets agree that the less boost you demand the more the WG has to flow.

High flow exhaust system. the increased flow airflow/exhaust through the motor will require the wg to divert alot more exhaust to create only 8PSI. The system is essentially out of balance. To rebalance the system we must either flow more exhuast through the turbo, or out the wg. Through the turbo would mean higher boost which is not an option. We must open up the wg, and possibly the dump tube into the exhaust to rebalance the system.

Respect
JET

 

Good points, common factors.

 

That still doesn't explain why there are people on this board making 420-450whp on this kit with the Evolution wastegate and not having this overboosting problem. That is, unless none have them have chosen to speak up. Then again, at that power level I don't think their motor would be in one piece if they had this issue.

 

well i think this might shine some light on this issue, well a friend of mine just got a kit and well i told him whats going on so we decided we were gonna check the wastegate before install and well he came to the conclusion that his wastegate would not open until it reached 13psi how ever i dont know how he tested it, but im pretty sure he knew what he was doing considering he is a mechanical engineer. now what he wants to figure out is why it takes so much to open it when there is a 8 pound spring in there,

what he thinks is that there is an imperfection inside the "piston" chamber of the wastegate which cause a blokage until there is enough pressure built up to actually move the "piston" up and out of the way. i should have more info by tommorow as he was gonna work on it tonight.

 

Simple answer..... As I said they are demanding more boost to produce that power. Less demand on the wastegate.

Respect
JET

 

No they aren't. These folks are running no more than 9.5psi (from what I understand).

 

9.5 is more than 8. 9.5 with a more restrictive exhaust system would be more in balance.

Respect
JET

 

That has to be it, the open exhaust will cause the boost to go up some and this might cause enough extra air to flow to overwhelm the wg and not bleed off enough air allowing more boost to keep building.