Over Boosting!

[Nizpro]

I have done more wastegates welded on garrett housings than I can remember and never had 1 crack.

I have never had 1 crack in anything ive ever made to be honest

As I said I would think that a company of your sandings would have tested this before releasing them to the public and its great to see a quality workshop with loads of experiance.

Cheers Simon

[XR6 Turbo Developments]

Great write up Simon and no I didnt take offence to what you said I am always open to opinions and advice.. Just to clarify what you have already mentioned there is alot more to venting gasses out of turbine than just porting and enlarging the hole. My argument was that I believed the same result could be achived by using a die grinder as opposed to having the housing CNCd. In saying that Now when I first strated modifiying XR6 Turbos I was told that making the wastegate hole round was the only way to do it. Everyone thought I was nuts and doing it wrong when I made the port a different shape but I insisted that's how I prefered to do it and kept my theories about it to myself. Now the funny thing is the people that thought I was nuts doing it the way I did have done there houisngs twice now! LOL!

Ive had a few customers from other workshops come to my workshop as there cars were still over boosting after having there housing modified. On removing the turbo and inspecting it there were 2 thing evident straight away. First was the size and the shape of the wastegate port which looked it had been opened up with a large drill bit. The other thing that cauht my attention was the throw of the swing arm. The actuator one customer had on his car had 7mm less throw. Combined with the so called ported wastegate he would of been better leaving the car the way it was.

Anyways thought id drop by and say hello!

[Fat-Tony]

I always was a bit dubious of the dremel approach to wastegate mods... how can it seal perfectly?

I assume Nizpro bores out their wastegate enlargements?

You don't take to the seat with a die grinder.

[SCRIBR]

oh, that's how I thought you guys did it

my bad!

[Fat-Tony]

One point, which is very important to consider is how turbulence in the dump pipe can effect wastegate and turbine flow. What effects this? Dump pipe design. Exhaust gases that are allowed to mingle and cross paths too early create turbulent backpressure in the dump pipe thus reducing the exducer and wastegate port flow.

Knowing that the above car has a Xforce 4 inch dump which basically allows the exhaust gases to cross flow paths pretty much straight away seeing as there is no divider at all might *cough* have something to do with it *cough*.

Would be interesting to bolt a twin pipe setup on it and have the wastegate duty left exactly how it is at the moment and see what difference in wastegate flow it would have. Would either support of not support the above hypothesis based on the data obtained from the factory map sensor. Although that said the weather conditions would want to be pretty much the same to give a controlled result.

Edited 05/05/08 09:03 AM by Fatsex

[Guest dico2020]

spoke to sexhead before, he said to check the actuator

hoses to see if one had come off. turns out the bottom one off the

solenoid had come off.

He told me to "hook the actuator line

direct to the turbo and see if the boost is ok".

I now have 12-13psi woot!

bugger, I kinda was looking forward to a screamer pipe!!!!

sorry leigh false alarm! ill still grab a remote filter off ya though!

and to anyone that cares, after over 10 years of being a close family friend I value danny's judgments and opinions and especially help. I wouldnt be driving an xr6t, id be driving a dyna truck if it wasnt for danny, or would have spent 3 times more on xr6turbo mods.

[Guest dico2020]

no seriously... a 1985 dyna

[RAP1D]

That was an easy fix, 20psi didn't sound right lol

[Fat-Tony]

That saved you pulling the turbo off, and I thought we had found the limit of your die grind port lol. Wouldn't mind seeing the difference in turbulent flow of the 4 inch and twin dump versions though.

Edited 05/05/08 09:41 AM by Fatsex

[Headsex]

Below is an example of how cheap pricing can cost more with an poor decision made alone on price

Headsex said this a few months ago

I do believe some turbo companies do a "exchange" program.. But enquiring to two of them, they were talking around the $350 - $400 mark.. bit rich in my opinion..

Now this gives consumers the opinion that 400 bucks is too expensive and that they can be done for less and yet Nizpro complete waste gate and turbine solution is $1180 drive away. The difference is ours works perfectly due to the parts we used and the development and testing we have done. If Headsex’s solution was $200 and it didn’t work its no longer cheap as some are now finding out. The next problem is that once these housing are incorrectly machined and if you still have over boost issue’s we cannot fix them so the housing is a throw away. A new housing is about $700 plus what you spent in the first place plus the remove and refit and you still have you get it fixed.

Now I don’t know who Danny uses or if he does them himself or who he was referring too I just used his quote to show how one person opinion who has little experience can influence peoples decisions only to find out latter it has cost them extra money to get the desired result. Consumers need to make sure they get proven parts for a proven result for a fixed amount. There will always be more than one way or the Nizpro way to fix a problem but please don’t base your decision on cost alone as its can be an expensive way to learn

Simon

When I initially got my wastegate port done, I was quoted from $250 to $550. I elected not to mention I was quoted that little back at the time I posted that. And no, I did not take the $250 option.

Then I purchased the complete Nizpro Plenum/Cooler/Airbox/Battery Kit from you Simon, and immediately on fitting the kit, I found I had over boosting problems. I was unable to bring boost under 17psi.

You probably recall the conversation we had, back when you were still doing your wastegate ports with a die grinder prior to getting them done by CNC. You mentioned there is a lot more to it than making the hole bigger, and to focus some attention to profiling from the flange to the flap to encourage flow from the exhaust manifold to the wastegate port.

This is when I took it upon myself to report the wastegate myself. This is my result. Commanding 0 Duty cycle in open loop, I can get a stable 12psi, Remembering, I also have a full exhaust with a 4" dump pipe to stir things up a little further.

This below is the standard port. Look closely where the RED arrows are pointing, this is the part of the housing that has alot of profiling done.

I agree not all jobs are the same, and some will most likely still overboost.

Now coming from an Aerospace engineering side of things, I see design to manufacturing every day at work, and a number of years ago, I also worked in an engineering shop decked out with a number of Okuma Lathes, Mills and a Siemens 5 axis machine.

A Mill will only be able to bore a bigger hole, and Re-seat the port, it will be unable to get in the housing to do the profiling. This is where you need a 5 axis machine to do the port for you. Knowing the implications of having to model an exhaust housing into a CAD package such as Catia, and then designing your modifications to the port, it only leaves manual programming in M or G-Code for instance.

I would love to see the MCode or GCode programming involved to put the level of detail into the profiling of the port as one could do by hand with a die grinder.