Good point.
The answer is: I have no clue. I did not see any obvious flaws, holes or anything; the layers of metal were firmly adhered to the gasket inside... and the gasket seemed to be adhered to the block and head(needed a crowbar to get the head loose).
I saw no evidence of leaking /into/ the combustion chamber(good).
The only thing I can think is that these gaskets need a really really thick and solid layer of a sealing compound; I sprayed on the copper gasket spray, but didn't let it dry and use multiple layers. I installed the gasket with the gasket spray tacky.

I also think at this point that retorquing the head studs is important; if it was a lack of flatness or something like that, it should have failed immediately, or during my 1,000 mile torture test... not a few weeks and few hundred miles /after/ that.

Here's pictures of the whole ordeal:

 

So, just wanted to give an update:
It's still running.

I haven't noticed any bubbles in the coolant, at least nothing that I could point to like before - No air escaping on shutdown or bubbles/pressure surging at idle.

Twice, I've had the heater hose come off the passenger's side port(once when I revved it to the governor in 2nd), and I've had a couple of leaks from the heater core-hose connection, but I'm pretty sure it's been lack of tightening the hose clamps down enough.

I've got the S360 turbo on it, and this time I couldn't find a T connector and never bothered to connect the boost gauge. So I'm not looking at pressures, just power/feel.
Power wise, right now it's... decent. It revs nicely, but doesn't have a lot of low-end grunt; requires more throttle input to get power and likes to smoke under load at the low end. The turbo just won't spool enough to clean it up. Up at 3K, yeah, it cleans up and has plenty of power... but not where I drive.

I've messed with the timing to try to optimize it; compared to what felt 'good' with my Banks and decompression gaskets I figure I'm about 4 degrees more retarded. It actually ran pretty well as-is, but retarding it slightly added power and reduced black smoke.
I tried retarding it a further 3-ish degrees, but it didn't really help and turned the black smoke into white smoke.
It's also /really/ laggy as a turbo, taking over 1 full second to spool up or down. It's enough to be able to upshift without the turbo despooling.

When I first assembled it, I didn't have one exhaust flange tightened enough, so I had a bit of a 'popping' noise; finally tightened it and got a slightly easier spool but not much.

I also ran it for a couple of days with /no/ exhaust system; pulled it from the downpipe back.
Obviously, it was quite loud(and sounded awesome), but didn't really change the performance.
I then swapped in a $50 "full boar" 3" glasspack muffler, with the "scoops" inside facing down the exhaust stream(i.e. louder and less restriction)... and it made it /much/ quieter than with my multi-chambered Thrush muffler. Didn't seem to change performance either.


My next step is to get ahold of a new Stage 1 or 2 cam from Justin, and a new set of USA made lifters, and swap them in - maby over Thanksgiving break?
I'm hoping that my slow spooling and lack of pressure out of the turbo is due to the stock cam, and a new cam will fix it.
Otherwise... I'll probably be in the market for a different turbo.

 

I've been following this thread since the start, I like seeing how your project is coming along.

Would the decompression gaskets maybe work best with a cam that bleeds off a bit like Justin's stage 1 or 2? I *think* all the other guinea pig engines were cammed besides yours.

Anyways, when you do the cam and rockers-- pics or it didn't happen!

 

If so... it completely defeats the purpose. I mean, I already had /less/ heat & pressure than stock(as evidenced by the smoking when cold, which is apparently typical), and bleeding off even more?
Yup, I'll definitely be doing that. I like taking pictures, though videos of the whole process has been hard due to trying to hold it....
Hm, I'll have to see if I can't come up with a hood mount and just video the entire process, speed it up by like 10x and put it on youtube.

 

Your S360 is one that Justin modded correct? With the amount of fuel you have, what rpm are you hitting full spool? I don't think that turbo should be spooling that slow even with a stock cam. Have you verified for sure that there are no boost leaks?

 

By sound, it's quite responsive and sounds like it should be giving me boost right off the line; I get plenty of whistle... but not much pressure.

Last I checked, I hit perhaps 12 PSI... at about 2800 RPM, or peak fueling... and the turbo feels like it would do quite nicely at say 4K... when I'm out of fueling.


Yup; this build I'm using 2.5" aluminum tube and silicone adapters, all tight. Not seeing anything that could leak enough to mean anything. And it did this exact same thing earlier, when I was using ABS pipe(completely different fittings for everything).

On the turbine side, I've checked and don't see or hear any leaks. Did have one earlier, which I fixed... but it didn't affect the overall feel very much.

And yes, I think it ought to work better. Justin mentioned that yes, he ceramic coated the intake housing at one point, and thought it ought to do good as well.

I just, for the life of me, cannot get it to build much pressure. And it's not like there's much too the darned thing, just a shaft and two wheels.
And yes, it spins freely... far more freely than my TE06H ever did. And you can hear it spinning down for a couple of seconds after the engine turns off.

 

I'm so confused why it won't spool. it should be hitting more than 12psi for sure! He a S366 hits over double that with stock fuel even on a stock cam I'm pretty sure. There has to be something we are missing... fuel pressure? I know you said it was black when it wasn't times correctly but maybe higher in the rpm you are hitting near zero...

 

Even so... If I'm getting smoke(and I can get plenty of it), I should be getting boost enough to burn that. I mean... if I can get 20 psi out of my little TE06H(which is /way/ more than it was ever designed for, well beyond the efficiency point), I ought to be able to get something decent out of a bigger turbo.

And I've been getting 20 psi out of that turbo every single time I run it - when I put the decompression gaskets on, I started with this S360, and got disappointing pressure. Swapped in the TE06H, and was able to hit 20. I've swapped back and forth several times.

 

I agree with you. I def think it should be making more. The S360 is only roughly 3mm bigger on the cold side iirc than your Banks turbo is that's what is confusing about the spool up. What is the AR on the hot side?

 

https://www.ford-trucks.com/forums/1...l#post16287836
It's supposed to be a .85 T3 housing.

Thing is... this turbo is physically about 30-50% larger. It /barely/ fits physically, with a lot less clearance than the TE06H, and the intake side is /much/ larger, at least the casting.

Suposedly, the specs on the S360 are: 60/84 for the compressor and 76/68 for the turbine.
The TE06H :
-- Some random forum post


Anyway... I can think of one of two things here:
1. Going to a better cam will change how air flows through the engine and improve boost; i.e. the stock cam is totally holding me back.
2. The exhaust housing being machined out isn't working as it should, angles are wrong or something.

In the case of 1, well, the cam will fix it. If not, I'll have to look into improvements.

I wonder if going with a much tighter AR, like the TE06H would fix it?
http://www.theboostlab.com/store/pro...-Housing-.html
Here;s a .63 AR, T3 housing that sure looks like it would just bolt up.

Any thoughts?

 

That would be a huge jump, I'd look for something a little over .70 A/R, I thing that with the increased airflow you would be making the bottleneck back pressure instead of no spool. The turbine wheel is comparatively huge so I could be wrong but, that just seems too small.

 

The question is, how to calculate that?
I know that that is the limit on the TE06H - beyond about 12 PSI, which I can hit up at 2400+ RPM, the efficiency goes out the window and the backpressure becomes really high. High enough to bend exhaust pushrods with stock springs.

This new turbo, though... compressor wise, it's 16% larger, turbine is 29% larger(area of turbine)
...Does that explain the lack of spooling? What with the drive ratios being different?
That being said, does this mean that, at 29% larger, I could use the same AR(.57) and get 29% more throughput?

 

Try to convert to CM to get a better idea of the housing size. A/R is a ratio and CM is a true measurement. CM versus A/R changes with the size of the housing. There is no set way to match these #s. Essentially, A/R is calculated from the area of the housing divided by the radius of the housing. Since it is a ratio, a bigger housing can have the same ratio as a smaller housing. It would just depend on what turbo it is. The chart below is an example of what I mean.

 

Here is how to measure the radius for the turbo. You can see it in this pic.

 

Can't we just use the radius of the turbine wheel? The housing radius will be almost exactly the same on the inside.
If we plug that in:
Area for TE06H: 19.15
Area for S360...
Housing was off of a S256, so 69.6 MM, at a .85 AR, 59.2 area.
Machined out for a S360, at 76 MM, would be a .78 AR???

Now, if I got a .63 ar housing, that would be 47.9 area, or 81% of the area...
In theory, this should give me 25% more boost?

Am I doing math correctly?