external wastegate plumbing

[80diesel4play]

got myself boost finally.
T3 external wastegate, so how the phuck do i plumb it to cater for the wastegate?

I know how the internal ones work - via the boost controller and opens the little port at the back of the exhaust turbine and off comes the boost.

So how do i make the external verison work and what do i need to make it happen? Got an Intercooler setup and it's for a diesel 80 4.2

[midi73]

I have the same problem. I am afraid that the only answer that I know of is to build an exhaust manifold with a waste gate built in to it. I have one but it is stuffed so I need to build another one. I am seriously looking at getting an internal wastegate turbo.
Dave.
PS. I can email some photos of it if you would like. ( I cant seem to post pics on this forum).

[red80]

External wastegat works similar to an internal one. boost pressure forces valve open dumping exhaust out via the exhaust port. It needs to have a flange welded to the exhaust manifold and usually fitted with a v-clamp. If you wish to up the boost you can bleed pressure to the spring side of the wastegate. eg if you have a 10 psi spring and you bleed 5 psi onto the spring side of the wastegate it requires 15 psi now to open it. They are alot better at holding boost than an internal.

[vSAHARAx]

A Question i know this is gonna sound typical teenagerish, but rice burners ( Turbo'd petrols) have a blow off valve that releases to atmosphere giving the noise that makes the car sound like its sneezing. Then some trucks during gear changes send out a noise caused by the turbo spooling down, thats really drawn out (sorta sounds like, CCHHHHHooooooooo, hahahaha sorry), is that noise cause by the waste gate and if so, is it possible to make a turbo deisel 4wd to make the same noise, cause it sounds tough. sorry if i have confused you or wasted 30 seconds of your life.

[red80]

The noise trucks make is just the turbo coming off boost blow off valves release pressure between the turbo and throttle body, when the throttle shuts the exhaust still turns the turbo. The blow off valve lets the pressure out to keep the turbo spinning without stalling, it also prevents the likelyhood of unscrewing the compressor wheel, diesels don't have a throttle so they spool down slower with engine revs. I am happy to be corrected if this doesn't sound right?

[vSAHARAx]

So is the reason trucks make the noise because trucks are running large amounts of boost? what is the average boost blowing into your average prime mover?

[red80]

I've heard 20 - 30 psi but not sure if that is correct.

[high n mighty]

Any turbo makes the noise, just that a petrol engine has either a wastegate fitted or doesn't. With a wastegate fitted the pressure is obviously releived via the BOV or without it fitted the turbo "stalls". You can hear the turbo spooling up through revs though.

With a diesel you generally dont have a throttle butterfly so a wastegate is not needed in these applications and also the turbo doesn't "stall", therefore you will hear it spooling down between gear changes.

When you hear a "CCHHHHHooooooooo" from a truck it is normally the exhaust brake dis-engaging as the driver is double shuffling up or down the gears, has nothing to with the turbo at all.

[puls8]

You still will need a wastegate in a diesel situation as the pressure activated diaphram within it will regulate the amount of boost you will run. Rather it is a BOV that is not really needed unless you would like the wanky noise. As it was stated a BOV simply relieves the pressure when the throttle is closed in a petrol engine situation, therefore venting excess pressure and preventing compressor surge, which is the fluttering sound you will here in some turbo engines.
To answer your first question, for the spooling sound, although it will make it more prevalent you dont need to run insane levels of boost, a simple way to increase the volume of the spooling would be to increase the size of your ehaust, dump pipe for a 4.2L probably a 3-3.5" mandrel bent pipe will be best suit with a 3" exhaust with highflow cat and mufflers to suit your tastes.
When plumbing the external gate you may join the pipe back into the dump as close as a smooth angled bend will allow however joining it further down the dump will give better performance (not going to be really noticed in this sort of setup). Better again would be to run a screamer pipe which is a separate pipe for the gate all together just run it out under the engine bay where it cant be seen. It will really give you lots of noise and better performance however it is illegal and i dont really reccomend it as cops will rape you and the benefits in your case are not really worth it.

[80diesel4play]

Hmmm - thanks for the input - been looking at turbosmart.com.au and the sleeper series of wastegates.

I think what I will do is get the 3" dump pipe (with insert for pyro) With the wastegate right next to the exhaust out part of the turbo. Then plumb the screamer pipe back at the bottom (first mandrel bend) so it meshes with the exhaust flow and crates no back pressure pulse.

Will be getting 3" straight through exhaust system - the turbo's quieten down the diesels heaps.

With the spring set wastegate - I will not be able to have variable boost though? YES/NO? Any thoughs?

Yes- will be getting intercooled so trying for 10&15psi at the turbo with 2 psi loss into the engine.

[red80]

You will be able to vary the boost pressure on an external wastegate. If you bleed for eg 10 psi onto the spring side of the diaphram in the wastegate (top), opposite the manifold side, you will require an extra 10psi to crack the wastegate open. Additionally if the incorperate a ball valve you can have variable boost, ball valve open 10psi more, ball valve closed spring set boost pressure. I hope this makes sense, if not I can try and draw a diagram and post it up.

[puls8]

Like Red80 said you can adjust the boost with a bleed valve/boost controller. Just get a wastegate spring of say 7psi and add a boost controller to that. Depending on the money you are wanting to spend i would reccomend that you electronic boost control will be alot more efficient for not only the workings of the car but easier for you to adjust boost when you require it but they are $500 and up. If you do not want to spend that sort of money just buy a manual controller about $100 and tee it into the wastegates reference point.

[balzackracing]

you may also get different springs for the turbosmart wastegates from the factory. how much boost do you want to run.??? the only reason youll want more boost is if your going to put in more fuel, check you exhaust temps at full load when setting up....

[spazbot]

Hmmm - thanks for the input - been looking at turbosmart.com.au and the sleeper series of wastegates.

I think what I will do is get the 3" dump pipe (with insert for pyro) With the wastegate right next to the exhaust out part of the turbo. Then plumb the screamer pipe back at the bottom (first mandrel bend) so it meshes with the exhaust flow and crates no back pressure pulse.

Will be getting 3" straight through exhaust system - the turbo's quieten down the diesels heaps.

With the spring set wastegate - I will not be able to have variable boost though? YES/NO? Any thoughs?

Yes- will be getting intercooled so trying for 10&15psi at the turbo with 2 psi loss into the engine.

now my understanding is u want to mount the wastegate on the custom manifold before the turbo, then the scramerpipe runs down into the dump pipe after the turbo, this will allow you to control the boost in the turbo, so when the boost reachs the desired level say 10psi, the wastegate opens and allows the exhaust to bypass the turbo compresser and limit the level of boost the turbo is creating.

or i could be completely wrong

[balzackracing]

That is correct

[80diesel4play]

Hmmm - thanks for the input - been looking at turbosmart.com.au and the sleeper series of wastegates.

I think what I will do is get the 3" dump pipe (with insert for pyro) With the wastegate right next to the exhaust out part of the turbo. Then plumb the screamer pipe back at the bottom (first mandrel bend) so it meshes with the exhaust flow and crates no back pressure pulse.

Will be getting 3" straight through exhaust system - the turbo's quieten down the diesels heaps.

With the spring set wastegate - I will not be able to have variable boost though? YES/NO? Any thoughs?

Yes- will be getting intercooled so trying for 10&15psi at the turbo with 2 psi loss into the engine.

now my understanding is u want to mount the wastegate on the custom manifold before the turbo, then the scramerpipe runs down into the dump pipe after the turbo, this will allow you to control the boost in the turbo, so when the boost reachs the desired level say 10psi, the wastegate opens and allows the exhaust to bypass the turbo compresser and limit the level of boost the turbo is creating.

or i could be completely wrong

That's pretty much it - was thinking of using factory exhaust nmanifold with 90 degree bent up U to top mount teh Turbo - with the wategate mounted underneath on front with screamer flowing down besdie into exhaust. I have had teh pump done and hi flowed injectors so fueld will be no issue - and am adding a pyro.

This should work yeah?

[chunderlicious]

will work fine, and the flutter noise you can here on most petrol turbo cars is the wastegate going off if you havent hit boost yet (where all you here is the blow off valve goin nuts) R33 skylines (my experience) flutter before boost, and then blow off after boost. if you set a blow off valve on a lower pressure to ur wastegate boost (the boost level) then you get an extremely irritating whistle, if you just run a screamer pipe off an external wastegate and dont dump pipe it then you have an awsome growel aswell is the spool of the turbo.

TURBOS ARE COOL, superchargers sound better

[80diesel4play]

well, Its all done now. Here's the deal! - I have pics but they are on my phone - just have to download and upload here - later on I will!

Made a U bend with 2.5" mandrel from the standard manifold, put the turbo on top of the motor(love body lift!), 2" mandrel to the Intercooler, 3" mandrel from the outlet to the 2 3/4" factory inlet that was modified to suit. External wastegate plumbed up between the U and the dump pipe.

Had 3" dump with pyro added, booty fabbed up to my 2.5" exhaust by Unique in Bayswater (they made the I/C piping as well.) so she flows okay for now. Still running the standard 80 series airbox - just turned around a little!

All booty fabbing and 90% of the work done by Sandy at AUS4WD. Many thanks to him for allowing me the space to build this up (as well as fix all the other stuff I had to!! - Low range, bushes etc...) as well as the constant - "just do it" advise!!

Running 9psi boost with 600C max on the pyro (4th gear full noise under load) she flies. We have yet to do a dyno run (once the compensator goes on it will), but the boost comes in very low, @1200-1300 rpm and goes all the way to the governor. I'd be interested to see dyno figures as you get pushed back into your seat considerably! Both Sandy and I were sceptical of how the setup would work and if the turbo was a goer (untested prior to turning key!)

Fine print.
Intercooler from gktech - the $200 ones from trading post.
Turbo from ebay (used t3 rotormaster) - $247 inc freight!
Boost compensator from swap meet (yet to be installed) - $60
External Wastegate from MTQ - Tial 38mm - looks mad. - @$600
Gauges from Morkz - go wee man! @$400
Plumbing from Enzed - $400
Exhaust and Intercooler plumbing at Unique - $600
Sandy's time and skill - Priceless.

Finally after 4 years of owning the 80 - I now how power to play!
Testing it at Cruiserkhana - loved it - so much fun in low range it's not funny! Well yes it was when I forgot the water balloon.....:(

[sniper]

pics pics pics please

[80diesel4play]

pics pics pics please

Your wish is my command...

[80diesel4play]

Been a couple of weeks now since doing it and it rocks!

[Toy80Diesel]

Been a couple of weeks now since doing it and it rocks!

bump! pics please!!

Any dyno news?

How much room left between the bonnet and turbo? As i have no bodylift..

Thanks!!