Compound turbo 3B (1 Viewer)

[cody c]

I have a couple of those td04L wrx turbos on my shelf as well. Mainlander ran one with good results for low end boost. He felt it ran out of steam around 2700rpm. It is on the smaller side, but is a good fit for the 3B in my opinion. Would work well for normal driving rpms. The compressor maps really well for it for higher boost, but you would definately need to upgade to a 360 thrust bearing.
The .63 housing is more common on older t3 turbos rather than the .48 as far as I have seen in the junk yards. I have a .63 but im running it as the large on my comounds. I also have a couple .48s but they are only really good for singles.

Huh, well if it runs out of steam by 2700, the larger one should hopefully be spooling up by then. Besides, the rev limiter doesnt give much room past that anyhoo. And the fact that I got a decent price on a turbo that apparently only had 79K miles on it.

 

[gerg]

Well the td04l compressor (13T) maps higher than that rpm wise, but the turbine is smaller so its most likely choking out. My larger t3 boost about 8 lbs at 2000rpm which is peak torque for the 3B. The turbo needs to be rebuilt so it can do beter than that.

I was going to chuck a HY35 on there and see what it does boost and egt wise. The t3 turbine is a mucho old school design and not as effecient as newer ones like the holset. In short it takes more drive pressure creating higher egts. Fortunately the td04 is a newer generation turbine wheel. Whats nice about the HY is that it uses a garrett bolt pattern so I think its a direct bolt on job with some exhaust welding which wouldnt be so bad. The HY 35 is the smallest of the larger holsets I have found. There is an HX30 but its compressor is too small to be a candidate as the large one in a compoundset up.

 

[cody c]

Well the td04l compressor (13T) maps higher than that rpm wise, but the turbine is smaller so its most likely choking out. My larger t3 boost about 8 lbs at 2000rpm which is peak torque for the 3B. The turbo needs to be rebuilt so it can do beter than that.

I was going to chuck a HY35 on there and see what it does boost and egt wise. The t3 turbine is a mucho old school design and not as effecient as newer ones like the holset. In short it takes more drive pressure creating higher egts. Fortunately the td04 is a newer generation turbine wheel. Whats nice about the HY is that it uses a garrett bolt pattern so I think its a direct bolt on job with some exhaust welding which wouldnt be so bad. The HY 35 is the smallest of the larger holsets I have found. There is an HX30 but its compressor is too small to be a candidate as the large one in a compoundset up.

Huh, well regarding the TD04L I figured it might be a little limited regarding CFM at that end of the RPM, but hopefully the other turbo will help pull air through it, though I suppose it may act as a bit of a restriction.

Ordered a 60mm exhaust BOV off of ebay today too, and called regarding 63mm housing. They said they will get the shipper to call me monday anyway.

So far I have the merkur turbo, subaru turbo in the mail, BOV in the mail, and a flange for the exhaust.

I guess I will wither need to order a SS T304 flange for the TD04L as well as for the exhaust output on it, then flanges for 63mm housing and exhaust and intake piping. Oh yeah and I should probably get the engine mounted in the truck at some point too I guess.

 

[gerg]

Now that you mention it, might be a good idea to fit the motor first.

The 13T is quite a capable compressor. It can do 20lbs up to 3000rpm with good A/F ratios and still be on the map. That is just the compressor mind you. Here is a rough map for you with 14lbs to 3000rpm. It would be difficult to find a better fit.
http://www.squirrelpf.com/turbocalc...&airflow6=0.129&airflow7=0.152&product_id=177

 

[cody c]

Now that you mention it, might be a good idea to fit the motor first.

The 13T is quite a capable compressor. It can do 20lbs up to 3000rpm with good A/F ratios and still be on the map. That is just the compressor mind you. Here is a rough map for you with 14lbs to 3000rpm. It would be difficult to find a better fit.
http://www.squirrelpf.com/turbocalc...&airflow6=0.129&airflow7=0.152&product_id=177

Hey Thanks!

Question(s):

Should I be plumbing the exhaust BOV to open on the smaller turbo's boost line or the larger turbo's output, or will it be a trial scenario where I play with it?

Flange's: anyone knopw the footprint of the TD04L or where i can find SS flange for it, same for the in and out on the 63mm housing?

 

[gerg]

So now as I understand it your calling it the exhaust BOV which is an external wastegate... correct? You will totally burn the crap and melt and actual bov as they are intended only for charge pipe after your turbo before the intake manifold.
Are you planning on designing your manifold with large turbo first on the exhaust side? If so then your welding will be easier for the wastegate (exhaust BOV) How you weld it and how it is hooked up to control boost are separate items. There are several differnt ways you can do it.
If you dont mind slightly higher hwy non loaded boost you could set the wastegate to say open at 20lbs total boost (big and little turbo combined boost) and it will work the little turbo hard in the lower rpms until total boost reaches 20. As the larger turbo boost more the little turbo will boost less and total boost will remain at 20 psi. This scenerio works well as you get to run a heavy wastegate spring and it wont leak at lower boost pressures.

The other way is to plumb the larger boost into the bottom port of your waste gate and the little turbo line to the top and set the waste gate to open at say 10lbs. Now little turbo will be limited to 10lbs at lower rpms and as the larger wastegate boost it pressurizes the spring end of the diaphragm and fights the little turbos boost signal so that little turbo will still only put out 10 psi even if total boost is much greater. It is very hard to actually tell the wastegate what the small turbo is boosting as boht turbos pressures are combined. This might not make any sense so forgive me i am building my deck and summer just arrived here in BC so im pretty sure I have heat stroke.

TD04L flanges. Not ss but mild I believe. Mild will weld on ok but you might get cracking depending what type SS you have.
http://www.ebay.ca/itm/370047922792?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2648

 

[cody c]

here's the wastegate Ive ordered: http://www.ebay.com/itm/28076873913...iewitem=&sspagename=ADME:L:OC:CA:3160&vxp=mtr

Ill have to ponder what you said for a bit, Ive been solo parenting and working on a fence all day with the neighbour and Im burnt.

EDIT: I think Ill run combined boost and a slightly heavier spring. I think it may be alright if the wastegate starts to open sooner, as I would think there would be a fair bit of restriction on the smaller turbo, and then the wastegate should be closer to fully open by full boost, taking most of the load off the smaller one.

I guess I might be "tuning" it for a while by playing with wastegate springs. The ebay add says it comes with a couple springs and is adjustable.

 

[gerg]

Yes I too am burnt. Forget what I wrote and just look at it as work the little turbo harder at low rpm with faster response with putting total boost to the wastegate with a heavy spring at say 20psi. This heavy spring holds the wastegate shut longer as most gates partially open at about 1/2 the set pressure. So set to 20 max, when boost reaches about 10 psi (1/2 max setting) your little turbo would begin to be cheated out of exhaust and manifold pressure. This makes your system more sluggish.

If you did it the second way and set it for 10psi, then the gate cracks a bit at 5psi. I hope you see what I mean. Both achieve the same max boost. One will help build low rpm boost sooner.

That looks like an acceptable wastegate except I believe it is a 60mm in on the bottom, and 44 out on the side. Most are designed that way and are misleading. I have only found one chinabay 60mm in and out gate. I wouldnt sweat it as yours is still more than acceptable.

http://www.ebay.ca/itm/320928692093?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2648

 

[gerg]

I wouldn't worry about small turbo restriction too much with low boost like this.
So say for example at 1500 rpm WOT with 20 psi wastegate your small turbo is making 10 psi and large is 5psi (total15). Wastegate cracks a bit but not much.
Then say 2000rpm small turbo is 10psi while large turbo is (total20) wastegate is open a bit more.
Then say 2800rpm where small turbo makes 5psi and large is making 15 (total 20) wastegate is open a lot more.
Now say your crazy and run at 3800rpm small turbo is making 0 psi and large turbo is making 20psi (total 20).
Get the idea. It doesnt care who makes what, just that it opens at 20. Now depending on your external wastegate size and design, the backpressure might force the small turbo to boost, but not a huge amount.
This allows that larger turbo to take over the work as the rpm rises. Its utilizing a compound design like a sequential, but you can always adjust the spring for more compound boost if you want.
fortunately, the 13T compressor housing is quite generous and shouldn't make a restriction on the intake side.

 

[cody c]

Well, the wastegate showed up in the mail yesterday, it looks great, if I ever have time Ill post some pics. I ordered the 63mm ehaust housing as well and am waiting on that too.

Unfortunately thats my expendable income for well, quite a while so I probably wont have much to report for quite a while, as I still need some SS pipe fittings to build the manifold and interconnecting exhaust parts, as well I will need to order exhaust pipe to build the whole system, get my motor cleaned up and bolted in the body. I think I may sandblast the 3B and put some paint on it first as well.

I wish I had the time and money to put into the truck, just dont have any to give it right now.

anyways, thanks for the info guys, I will revive this thread and post pics whenever some progress eventually happens to it.

 

[cody c]

garret versus the TD04l and the new exhaust housing.

It'll be a while before I purchase anymore parts to assemble this, Im planning on three inch straight pipe all the way through, dont think Ill put a muffler in but that may change if I find it too noisy.

The TD04L needs new bearings, the seller said it only had 79K miles on it, but its got too much play, the garret in comparison is tight.

You can see the wastegate should be big enough.

 

[Dougal]

How much is too much play? Is it hitting the housing?

 

[gerg]

Thats cool cody. I have read that actual Tial wastegates of that design claim that it can flow like 400 cfm with only 1lbs of backpressure. Should be more than enough for what your using it for. I would recommend lapping in the wastegate with valve compound as when I got mine it leaked until I did that. The material was good, just needed a better grind I guess. I also had to port the sharp inners of my wastegate, but your is a very smooth improved design.

Muffler is not needed, but a resonator or something like that might be helpful as I hear almost no engine noise out my tailpipe, just turbine whine. Now although the wine is mucho kewl, it is quite loud. If you run it out by the passenger rear door a glass pack or something might be helpful. If you go all the way out the rear bumper then id say you could do straight pipe for sure.
G

 

[cody c]

How much is too much play? Is it hitting the housing?

no, but its pretty close.

The exhaust will run all the way out the back of her.

As much as I love the purr of a diesel, engine noise on my 80 is getting old, Id like a quieter truck when I get the hilux together, but then again iitll be on 40" iroksa annyways.

Maybe Ill sell the 80 and get a more appropriate DD, though Id kinda like to DD a 4 door hilux with twins on 40's too.

 

[Dougal]

no, but its pretty close.

No problem then. Run it.

Greg, your inbox is full.

 

[cody c]

No problem then. Run it.

Greg, your inbox is full.

Oh, can do.

 

[cody c]

does anyone know of a dual needle boost gauge, say 0-40 or 50 psi scale?

been looking on the internets...

 

[gerg]

I run dual guages, 1 total boost and the other large turbo boost.
hey thanks for the pics of your 80. Nice truck.
g

 

[cody c]

I run dual guages, 1 total boost and the other large turbo boost.
hey thanks for the pics of your 80. Nice truck.
g

no probs, I assume your large turbo is on the intake side of the smaller turbo then?

I think having dual needles, (first turbo and then combined) will give me a better comparitive perspective then looking at two seperate gauges, then trying to do the math in my head.

I did find two places actually..

http://designatedengineer.com/index.html

http://www.kennedydiesel.com/categoryresults3.cfm?Category=7&SubCategory=104&SubCategory2=188

 

[gerg]

That is so neat. I like the one that goes to 80lbs and the idea of measuring drive pressures and boost on the same gauge. I think ill have to upgrade.
yes the large turbo boost feeds into the small one as Im not sure how it would work the other way around. I think the little turbo would overspool like crazy.