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michaeli
13-01-2006, 06:25 PM
Hi Guys,

For the more technical users, has anyone ever kept the turbos but changed/ported the wastegates?

I've come across this (http://www.funkystyling.co.uk/item_detail.php?prodID=803) you see....

What effect would this have if any?

Thanks,

Mike

SGHOM
13-01-2006, 06:31 PM
At £918 + postage, it can have any effect it wants !! :rolleyes4 It ain't going on my car !! /grr :embarasse :embarasse

bradc
13-01-2006, 07:55 PM
Uc's car has 2 external 38mm wastegates, they are giving him problems at the moment, when he tries to run above 10psi, but his car does make 205kw ATW

michaeli
13-01-2006, 08:01 PM
So it will have an affect on Power... /yes


Any ideas on max power output possible by changing wastegates and not turbos??

Can changing the wastegates be changed without taking engine out??

UC - what are you experiencing and why did you go this route??

Thanks,

Mike

michaeli
13-01-2006, 08:06 PM
Just found this which explains alot....


Let’s begin by describing what a turbo wastegate is. A wastegate is essentially a device that bypasses some exhaust flow around the turbine section of a turbocharger to control maximum boost. A wastegate is usually controlled by a pressure actuator that is connected to manifold pressure. The wastegate is normally closed, held shut by a spring inside the actuator canister. When preset pressure limits are exceeded, the actuator progressively opens the wastegate, allowing exhaust flow to bypass the turbine, thus regulating manifold boost pressure. On the surface, it sounds like a simple premise, and in fact, a wastegate is a simple device. The problem comes from the pressure in the exhaust system, called turbine inlet pressure that can bear against the valve, overpowering the spring in the actuator, and forcing the wastegate open at lower than intended boost levels.

Original equipment turbocharger wastegate actuators are selected or engineered for a specified boost level and turbine inlet pressure. To keep costs down, such actuators are usually just big enough to do the job at the stock boost levels. If the turbocharger boost is increased for additional airflow and performance, the stock wastegate actuator is frequently incapable of holding the wastegate fully closed until the higher boost level is reached. This happens because turbine inlet pressure also increases as boost pressure rises. The fix is to use a bigger spring in the wastegate actuator to hold it closed until the desired peak boost is achieved, however, that also requires a bigger actuator diaphragm to override the heavier spring when the desired boost level is reached. That’s why Banks created the Big Head actuator that’s used on many of its diesel power systems.

The net affect is that the turbocharger comes up to peak boost more quickly and then maintains that boost level throughout the engine’s RPM range for optimum mid-range torque and top end performance. It’s another example of the engineering expertise you get from Gale Banks Engineering. We do it right.



The above will explain why when people up the boost and it drops off at the top end...




So, is it possible to change wastegates without taking engine out?

michaeli
13-01-2006, 08:16 PM
And this is very good too...


Inside the wastegate is a diaphragm which creates a seal, and a spring which holds the wastegate closed. Spring rates vary depending on the amount of boost you want to run, typically they are given in a "bar" value for example 1 bar would be 14.7psi. This would mean that in order to open the wastegate you would need to excerpt a greater pressure than the 14.7psi spring holding the wastegate closed. In order for the wastegate to work you must have the compressor reference port hooked up to the compressor side of the turbo, if you don't have this vacuum line attached than the boost pressure will not be limited to the set spring pressure; it will build unlimited boost pressure until your engine is destroyed.

Normally pressure from a spooling turbo pushes against the diaphragm (though the vacuum line attached to the compressor reference port) which in turn pushes against the wastegate spring. When the pressure from the spooling turbo exceeds the spring pressure the wastegate's plunger opens releasing the excess pressure through the dump tube into the exhaust after the turbo or to open atmosphere. Typically, if you use the wastegate to control your boost levels you will experience a decrease in power and spool times. Why? Although the spring fully opens at its set spring pressure it tends to begin opening before reaching the set spring pressure. This "pre-opening" leaks boost pressure through the dump tube before max boost pressure is reached resulting in a decrease in power mostly toward the top end. This can be corrected by using a boost controller.


Boost controllers serve two functions; increase boost levels beyond the set wastegate spring pressure and reduce the "pre-opening" of the wastegate-controlled boost pressure.




As your turbos get older, your wastegate spring will get weaker, causing boost leak, so you get a boost controller to counteract this, but it will still pre-open and cause boost leak, whihc leave 2 options:

1) replace the springs in the wastegate or upgrade it
2) replace the wastegate (and turbos)

Kieran
13-01-2006, 08:18 PM
So, is it possible to change wastegates without taking engine out?

Errr. Not sure as I've never looked but I imagine doing all that fiddling with it in situ would be hugely awkard - In fact I bet it's nigh-on impossible on the rear turbo.

michaeli
13-01-2006, 08:38 PM
You see, please share your wisdom....

bradc
13-01-2006, 09:02 PM
He is coming into my work today, I'll hit him over the head, and tell him to reply to this topic :)

I think his engine was out when it was all being installed. The main reason he went with them was the noise from the screamer pipes, the extra boost control is just a side effect :)

mitzylongboy
13-01-2006, 10:27 PM
michaeli..... mate!! if you want new BOV's find something cheaper. you got that baby coming..remember? you're looking at £2,000 + fitting!!
maybe you should start getting your nappy supplies. lol
in all seriousness i have seen a couple of pikkies with aftermarket BOV's and it appears the back one is VERY close to the ground. the owner did actually state it's close to to scrapping the ground!

mitzylongboy
13-01-2006, 10:31 PM
looks close don't it?

Kieran
13-01-2006, 10:33 PM
He's not on about BOVs though! He's on about ninja-spec wastegates!

Rossco Type-S
13-01-2006, 10:34 PM
michaeli..... mate!! if you want new BOV's find something cheaper. you got that baby coming..remember? you're looking at £2,000 + fitting!!
maybe you should start getting your nappy supplies. lol
in all seriousness i have seen a couple of pikkies with aftermarket BOV's and it appears the back one is VERY close to the ground. the owner did actually state it's close to to scrapping the ground!

BOVs are not wastegates!

michaeli
13-01-2006, 10:35 PM
Don't worry, they wouldn't be the ones in the link... /pan that was just the spark for the idea really.... /Hmmm

I was thinking along the lines that if I don't need to take the engine out then I could uprate the wastegates fairly easily and for less money/time than changing turbos... :scholar:

It entirely depends on the turbo flow... what was the CFM of our turbos again? Valmes?? /help

If I changed the wastegates, this wouldn't change the CFM though... would it??

Nick Mann
13-01-2006, 10:40 PM
It entirely depends on the turbo flow... what was the CFM of our turbos again? Valmes?? /help

If I changed the wastegates, this wouldn't change the CFM though... would it??

Not enough.

No.

Sorry to p!$$ on your bonfire. :embarasse

michaeli
13-01-2006, 10:53 PM
How much more BHP could we get with a better wastegates??

Nick Mann
13-01-2006, 10:57 PM
Assuming your wastegates are functioning properly, not a lot. AFAIK the wastegates are shut to hold pressure. The pressure drop at high revs is a flow problem, not a wastegate problem. The simple fact is that to get high 300's (without the use of laughing gas!) we need to flow more air. Our little turbos can't do it. I'm sure better wastegate control would help, but at anywhere near the costs you have posted up there the better option would be turbos with more flow. In my humble opinion!

You See
13-01-2006, 11:01 PM
UC - what are you experiencing and why did you go this route??
Do it, but those HKS ones are way too much for the standard turbos, it's best to stick with the smallest possible as in my case the wastegates dump it all out too quick and therefore the turbos aren't able to hold peak boost (boosts up to 14 then drops back to 10psi)
I was recommended to re-route the piping from where the wastegates flange are on each manifold and joining them to one.....thus only using 1 wastegate and allowing both turbos to spool and hold boost.
I went this route mainly for the noise....sounds awesome! :thumbsup:


You see, please share your wisdom....
It was only 8am when you guys were posting, on a Saturday I'm allowed to sleep in....aren't I?..lol /pan

michaeli
13-01-2006, 11:02 PM
You're probably right Nick....

At least we got to a conclusion... Kind of...

I'd still like to know what UC has experienced...


Nick
Is the above wastegate info I posted worth making a sticky??

michaeli
13-01-2006, 11:08 PM
Ooops... posted at the same time...



Do it, but those HKS ones are way too much for the standard turbos, it's best to stick with the smallest possible as in my case the wastegates dump it all out too quick and therefore the turbos aren't able to hold peak boost (boosts up to 14 then drops back to 10psi)
I was recommended to re-route the piping from where the wastegates flange are on each manifold and joining them to one.....thus only using 1 wastegate and allowing both turbos to spool and hold boost.
I went this route mainly for the noise....sounds awesome! :thumbsup:



Ooohhh... post the sound... sound is always good... /Hmmm /Steeringw :thumbsup: or at least describe it!!!



It was only 8am when you guys were posting, on a Saturday I'm allowed to sleep in....aren't I?..lol /pan


Yes, whever I'm not asking you a question.... /pan (Only joking)



What BHP increase did you get?
What problems are you experiencing that Bradc mentioned?
WHAT DOES IT SOUND LIKE??
Would I have to remove the engine?

You See
13-01-2006, 11:12 PM
I'd still like to know what UC has experienced
Power-wise, I'm sure there was an increase there somewhere.. :inquisiti ...Have found the turbos do spool up quicker and are more responsive...tho there could be due to many factors (Air filters, Intercooler or ECU)
If you were considering the HKS one, I would recommend you don't...and go for a smaller (and cheaper) options. That way you'll have $$$ for those turbos too! :thumbsup:

You See
13-01-2006, 11:23 PM
Ooops... posted at the same time...
Actually you were beaten by a minute! :evil2:

What problems are you experiencing that Bradc mentioned?
Cos the wastegates open around 3,000rpm, it dumps everything out and our tiny turbos aren't able to spool quickly enough to hold max. boost and thus dropping back off to 10psi.

WHAT DOES IT SOUND LIKE??
Think of the noise a lion...purring then all of a sudden attacking! (hey, I just woke up and not feeling too descriptive!)

Would I have to remove the engine?
No you wouldn't, you would have to remove the turbos and the manifolds (obviously to take out the internal gate and make a wastegate extension/flange on the manifolds)

bradc
13-01-2006, 11:53 PM
the best way to describe it in letters is WHHHHHHHAAAAAAAAPPPPPPPP it is really really loud, and is absolutely great. We'll have to put together a sound file for you guys

jakester
14-01-2006, 12:44 AM
Screamers are the bomb :), I ran one on the Skyline for a week, then the police advised me to take it off if I were going to continue scaring cyclist so bad that they fell off thier bikes, literally :)

Quail
14-01-2006, 01:37 AM
Ive still never heard a screamer in real life yet. Im missing out!

AllBeItMine
14-01-2006, 02:27 AM
putting external wastegates on the existing turbos is overkill imo.

a 38mm wastegate is more than twice the size of the ones fitted to the td03's and 38 is the smallest i have heard about.

the internal wastegates on the turbos work fine and are not the bottle neck as the turbos on the car are incapable of generating enough power to generate enough exhaust gas to warrant larger wastegates.

this is proven by You See, whos car has twin externals fitted and the turbos still do not hold boost through to the red line, running out of puff even after some expert tuning.

there are some pro's to fitting externals however. firstly if you have a fancy electronic boost controller, it will be able to open AND force close the wastegates using the secondary input on the wastegate diaphram.

secondly - if you have upgraded your turbos, the positioning of them on the car might force you to ditch the internal wastegates in favor of using externals allowing you to position them where you need them to be.

bradc
14-01-2006, 06:00 AM
They are definately overkill, I definately agree with you there ABIM.

michaeli
14-01-2006, 09:45 AM
Ok... :embarasse Would I be able to change the turbos without taking the engine out? :inquisiti

Would it be advisable? :rolleyes4

Oh and I also need to change the clutch, so if it's engine out for this, it will all be at the same time... bit nervous though... /help

bradc
14-01-2006, 12:12 PM
I doubt you would be able to change the turbos without removing the engine. If you are looking at a twin setup, I would recommend TD04's or GT25R's. For a single, you're probably best to look at a GT30 or 35 hybrid of some description.

michaeli
14-01-2006, 01:15 PM
Thanks for the advice...

I am going to go for the TD04H-16T-6CM2 like valmes.. Seem to flow well and match our engine and will fit with relative ease.. /Steeringw


Now I was planning on fitting my emanage Ultimate before and getting it running, then take the engine out, replace the turbos and get the engine back in and tweak the ultimate again.. :thumbsup:

Does that sound more sensible than trying it all at once?? :inquisiti

Nick Mann
14-01-2006, 06:15 PM
Nick
Is the above wastegate info I posted worth making a sticky??

Probably better in the library? What do others think?

AllBeItMine
14-01-2006, 09:10 PM
Thanks for the advice...

I am going to go for the TD04H-16T-6CM2 like valmes.. Seem to flow well and match our engine and will fit with relative ease.. /Steeringw


Now I was planning on fitting my emanage Ultimate before and getting it running, then take the engine out, replace the turbos and get the engine back in and tweak the ultimate again.. :thumbsup:

Does that sound more sensible than trying it all at once?? :inquisiti

from experience i offer you this advice (especially if you are doing it yourself)

DONT TAKE THE ENGINE OUT UNTIL YOU HAVE EVERYTHING YOU NEED. (not that you will be able to think of absolutely everything but having most stuff will save you sooo much time)

so, make a shopping list:
You will need the turbos (so far the cheapest part of my whole conversion)
flanges for the heads and turbos made up so you can start on your manifolds
flanges for the dumppipes on the turbos to remake the downpipes of your exhaust system
oil and water lines matched up to the turbos and feeds. at least buy the relivant connectors and lines and have them ready for when you need them
wastegates. (for my project the positioning of the turbos and rotation of them ruled out using the internal wastegates)
new piping: from the turbos to the intercooler and the turbos to the AFM will need to be replaced. if you are using a blue emanage you will be keeping the afm so may as well do a good job of it.
your new clutch.
your new set of injectors and your new fuel pump. (you see has 205kw at the wheels on the standard turbos and the fuel system is running at 85% so we can say that the car has about 230kws in it on a good day maxing out the fueling.) If you are upgrading your turbos you will obviously want more than this so you need injectors and fuel pump, possibly fuel pressure regulator as well.
get yourself all the gaskets you need
change the cambelt while the engine is out as well if it hasn't already been done. i did mine took about 30mins with the engine out. saves you paying 6hours labour to somebody else.
same story with the waterpump.
buy 2 large high flow slimline radiator fans.
budget to spend around 4-500 on steel for fabrication. the good stuff isn't cheap and the cheap stuff isn't good.
budget 750-1000 for each manifold if somebody else is doing it.
samco - lots of samco.
keep in the back of your mind that you will need to modify your oil filter asembly, possibly an engine mount depending on placement,

now. the reason i say buy everything you need first, or at least make a shopping list is for a couple of reasons.

firstly - people think about upgrading the turbos on their car, see a turbo for sale on ebay for $400 and think that will be the total cost (or at least the most expensive part of the upgrade) - its not.

secondly - the biggest killer in my project was waiting for parts, or finding new things i hadn't budgetted for. so take my advice. its meant well. i've been driving a ****ty blue mazda now for 4 months cause i didn't think ahead far enough.

the easiest part of my entire project was taking the engine out and puttting it back in again. it came out in about 4 hours and went back in in the same time. and that was just 1 guy doing it. so stop worrying about that.

final piece of advice - A creative visualisation is not a replacement for an acurate measurement. i stopped thinking to myself - YEAH, THAT WILL FIT pretty early on in the game.

AllBeItMine
14-01-2006, 09:12 PM
Now I was planning on fitting my emanage Ultimate before and getting it running, then take the engine out, replace the turbos and get the engine back in and tweak the ultimate again.. :thumbsup:
Does that sound more sensible than trying it all at once?? :inquisiti

yes. get the car running perfectly on standard turbos with the emanage then you can rule out any funny stuff as being the emanages fault when you put the turbos in.... it will also give you a good understanding of what all the wires and hoses do in the engine bay before you find yourself with them all in one hand and an empty engine bay in the other :thumbsup:

AllBeItMine
14-01-2006, 09:15 PM
oh - i also noticed (back to the wastegate thread) that the link above is to an HKS 50-60mm external...

these are used on 1000hp drag cars. they probably have a minimum spring pressure of 35psi. so could we please put that topic of fitting one of those to bed?

hehe - on a funnier side: putting two of those wastegates in your engine bay would do a good job of hiding your engine - they are fricken HUGE!

bradc
14-01-2006, 09:50 PM
Great post ABIM. Uc's car when originally tuned had 198kw ATW, but the fuel pump was maxed out. Now he has a walbro 255lph and as you said, his injectors are at 85%. I had read somewhere though that you shouldn't run your injectors above 85% anyway, so I think a guideline that should be stated is that you should change your injectors once you get above 200kw ATW.

I would also suggest that anyone changing turbos should change to MAP and have an airfilter off each turbo, did you see Rhys's post about how small the stock pipes are, especially to the front turbo? They may be ok for TD03's, but for anything bigger you should do something like what Uc has done.

richy rich
14-01-2006, 10:03 PM
Assuming your wastegates are functioning properly, not a lot. AFAIK the wastegates are shut to hold pressure. The pressure drop at high revs is a flow problem, not a wastegate problem. The simple fact is that to get high 300's (without the use of laughing gas!) we need to flow more air. Our little turbos can't do it. I'm sure better wastegate control would help, but at anywhere near the costs you have posted up there the better option would be turbos with more flow. In my humble opinion!
totaly agree nick :thumbsup:

michaeli
14-01-2006, 11:00 PM
Great info ABIM!! Thanks... :thumbsup:

Some serious food for thought!!! /help



Just to clarify, I wasn't planning on putting those particular wastegates in my engine, I was merely using it as an example of an upgraded wastegate to start the thread off.... :inquisiti :rolleyes4