1951 Cockshutt 30–1.9L TDI Swap

[CTD2500]

Would like to see your charge air cooler between stages. Any pics? I'm assuming its air to air...

70 psi boost with 60 drive that's very good regardless of how hard the primaries are pushing! You would likely have more pressure between stages without charge air cooling (assuming that its both cooling the charge and not restricting flow). Would be nice to see the turbine speed on the manifold turbo. Actually you might benefit from losing the cooler between stages if it raised the between stage pressure by only 5 psi lets say. 18 psi doesn't make too much heat. 70 psi is plenty though for your truck,no need for more.

I finally broke down and bought the garrett turbo speed gauge for the manifold turbo on my TDI car. My wastegated s362 Villian is currently set to run 90-100k rpm. At 4500rpm under full load the Intake manifold pressure was 125 psi and drive pressure was 55 psi with 45 psi boost between stages (s475/87mm with air to air between stages) .

I’ll have to take some new pictures of the interstage cooler and how it’s routed. Pics I had back when I built it are on old devices.

I think it was 2015 that I added the interstage cooler, and I was able to set it up so I could quickly reinstall the non-interstage pipe and drive it back to back to compare. I don’t recall seeing much difference in interstage boost (I think I was running a GT42 for a primary at the time), but I remember full power being smokier and maybe a little weaker without interstage cooling, but the trade off was that having the secondary draw through all that piping, an intercooler plus the primary turbo made spoolup off the line noticeably worse.

To fix that, (mostly) I added a check valve with another air filter just before the secondary compressor inlet so it could draw air easier, then the check valve closes when primary boost begins. This many years later it still works seamlessly; you wouldn’t even know the check valve is there.

The last primary I was running was an S372 sxe with a 1.0 housing. Primary boost was in the high twenties at full throttle. These two 57mm units should outflow that by a decent amount (65 lb/min each for 130 combined) so I expected at least the same boost from them. When it was that low, I wondered if the turbines I’d picked for them were too big and not allowing proper drive pressure to build, but when I hooked up the gauge to the hotpipe and saw 30 psi drive pressure it made me wonder about an intake leak. I ran a 57 sxe like these on the manifold before this setup and at 30 psi it was 1:1 drive/boost. Granted I don’t know how much the primary pressures affected that, but it seems to me that for 30 drive, boost should be higher—assuming running two in parallel act the same as a single. This is kind of uncharted territory for me, lol.

I suppose it’s possible that the cooler might be small for this much air? It’s the most primary I’ve ever ran by a big margin. The interstage cooler is a Treadstone TR1235, which is 12.5” tall, 3.5” thick with a 22” long core, if I remember right. 1142 CFM, according to the website. I’ll admit, I’m not an expert at sizing coolers, I just bought the biggest one I could fit in the space I have. I guess I could try reading primary boost before the cooler if I don’t find any leaks.

Am I reading your post right? Are you running a 62/75 setup on a TDI???

 

[Powerstroke Cowboy]

To fix that, (mostly) I added a check valve with another air filter just before the secondary compressor inlet so it could draw air easier, then the check valve closes when primary boost begins. This many years later it still works seamlessly; you wouldn’t even know the check valve is there.

I like that idea a lot! What size Valve and what make did you go with?

 

[CTD2500]

I like that idea a lot! What size Valve and what make did you go with?

I do have pics of that. It’s a Techno valve with 3” NPT threads, but a 3.5” air filter fits it.

To attach it to the pipe, I used a 3” NPT cap and cut a saddle shape into it so it could be welded onto the side of a 3” charge pipe. Then a passage was cut into the pipe to let the air enter, and the check valve is threaded into the welded cap.

The end result looks like this, and the filter protrudes into the right corner of the front bumper after leaving the interstage cooler.

I’ll try to get pics of the whole routing of the cooler system later today.

 

[andy2]

That check valve is a genius idea. I'm pretty sure that your interstage cooler is big enough. Is it possible that the check valve is currently leaking? Did you try blocking it off to see if interstage boost goes up?

I think that your new vgt is moving alot of air and that is the reason for the lower boost pressure reading between stages. I'm sure it works well and has good transient response so I might not bother changing much.Looks like those primaries are a bit small on both compressor and turbine side.

The compounds on my truck only make 18-20 psi between stages but it responds quickly between stages and I feel that's important.

Yes 62/75 turbo's on the TDI. The s475 had the 87mm turbine wheel in it and now I have the 96mm turbine wheel going in as well as a taller 75mm compressor wheel.

 

[CTD2500]

That check valve is a genius idea. I'm pretty sure that your interstage cooler is big enough. Is it possible that the check valve is currently leaking? Did you try blocking it off to see if interstage boost goes up?

I think that your new vgt is moving alot of air and that is the reason for the lower boost pressure reading between stages. I'm sure it works well and has good transient response so I might not bother changing much.Looks like those primaries are a bit small on both compressor and turbine side.

The compounds on my truck only make 18-20 psi between stages but it responds quickly between stages and I feel that's important.

Yes 62/75 turbo's on the TDI. The s475 had the 87mm turbine wheel in it and now I have the 96mm turbine wheel going in as well as a taller 75mm compressor wheel.

Crap, I just realized I never took pictures of the routing for the interstage cooler! I’ll have to get on that soon. Anyway, I did get around to pressure testing the system last weekend, and wow. There are leaks.

Most of them are in that 2” y-pipe. Pretty much every weld has leaks, and two that are big enough that the soapy water won’t even bubble because it blows out too hard. You can hear and feel it with your fingers. There’s a leak down near the check valve too. The guy who does my welding for me (I just have a 120v flux core welder) usually uses a TIG, but this time he used the MIG to save time, but obviously it didn’t work out too well. I’ll have to strip the paint off and bring it back. No big deal, he does it for me for free.

So that needs fixing and then I’ll see how it runs.

As for the check valve, I was hoping I could pressure test it too, but it needs a good bit of flow to snap shut and the pressure tester fills the system too slowly for that to happen. So I had to cap it off to test the system. I assume it’s holding decently since it was there with my old compounds and there were no boost issues then. I can test drive with it capped off though, like you said, after the welds are fixed. The weld near the check valve that is leaking is a new section; when I built these triples, I increased the pipe size from 3” to 3.5” after the check valve to help with flow to the manifold turbo compressor even more.

As for the tractor, I was finally able to finish stripping the rear end of the chassis the other week. After fixing/modding a few more little things, I just have to seal up the openings and it can be painted. I’m hoping for a fully restored chassis by the end of August.

And that’s a lot of turbo for a TDI! I didn’t think they would spool all that, although you spin a lot of RPMs on that thing, no?

 

[andy2]

Hopefully fixing those leaks will increase the pressure a little but I wouldn't count on it. Can you rework the housings for bigger wheels yourself? Mabye 64mm turbine wheels and 62mm compressor wheels.

Moving along nicely with the tractor. You'll soon have all of the hard work done by the looks of it.

Yeah my TDI engine continues to surprise me in terms of air flow. I made an under fueled pass a month ago and there was no sign of compressor surge/stall from the s475 while shifting into 5th gear and pulling the engine down to 3800 rpm in 5th. The 87mm turbine was the bottleneck in the system. I can leave the line with 80 psi+ boost before loading the engine with the clutch.

 

[CTD2500]

AGP turbo has a 62mm version of the S200, but it uses the same 61.5mm turbine. I’m not sure what’s available for s200s on the hotside, aside from the older 11 blade versions of the 64/65mm wheel.
As far as machining goes, I have good turbo guy local to me who can build pretty much anything.

 

[Powerstroke Cowboy]

I do have pics of that. It’s a Techno valve with 3” NPT threads, but a 3.5” air filter fits it.

To attach it to the pipe, I used a 3” NPT cap and cut a saddle shape into it so it could be welded onto the side of a 3” charge pipe. Then a passage was cut into the pipe to let the air enter, and the check valve is threaded into the welded cap.

The end result looks like this, and the filter protrudes into the right corner of the front bumper after leaving the interstage cooler.

I’ll try to get pics of the whole routing of the cooler system later today.

I'm not sure how I missed this reply? Thank you for showing how and what you did!! I think it's a brilliant idea!

I wonder how much difference those boost leaks will make? My brothers truck (semi) had a intercooler leak that was so bad that we couldn't even get it to build pressure when trying to do a boost leak check. But, it would still build around 35 to 39 pounds depending on ambient air temperature.

To be fair though he changed the turbo after fixing the leak. So we.never did get to see what it could.have done leak free.

 

[CTD2500]

I'm not sure how I missed this reply? Thank you for showing how and what you did!! I think it's a brilliant idea!

I wonder how much difference those boost leaks will make? My brothers truck (semi) had a intercooler leak that was so bad that we couldn't even get it to build pressure when trying to do a boost leak check. But, it would still build around 35 to 39 pounds depending on ambient air temperature.

To be fair though he changed the turbo after fixing the leak. So we.never did get to see what it could.have done leak free.

They need fixing regardless, so we’ll see how much loss in efficiency it’s causing. I still don’t feel right about it easily hitting 30psi drive in the interstage while barely hitting 18 boost. But again, it could just be the way triples run, or compounds with a VGT. If primary pressure is lower, but volume is good then so be it. Overall boost is 70, after all.

I don’t know, I’m only used to normal compounds with a wastegated secondary!

It would be interesting to have a second truck to try one of these little primaries as a single, then I could watch boost vs drive in a simple, leak-free system. The .78 housing on them I think is a Garrett based housing modified to fit the Borg; it’s not common on an S200 so I can’t find much info on how they flow.

Oh, and I forgot about one of the other S200 options; Borg’s product listing shows a new s200 SX-R, which has the same turbine wheel, but a new 57mm compressor that flows over 70 lbs/min, about the same as the current 62 SX-E. But it could just be a 62mm wheel with 57 listed by mistake. I can’t find anything else about it anywhere.

 

[Powerstroke Cowboy]

One thing I wish Borg did was have a flow chart for the turbine side of their turbos.

The high drive pressure could simply be because there's not enough turbine flow?

I agree, the boost leaks need fixed regardless.

 

[CTD2500]

The S200 has a pretty good flowing turbine wheel for its size, better than an HE351 or HX35, but I think housing selection can mess things up easily if you go too small. I had a hard time deciding on the .78 or the .82, but ended up going with the smaller one. Kinda wish I could try the bigger one without a lot of work, lol.

Anyway, I forgot again until just now to take pictures of the intercooler routing. It was my daughter’s final baseball tournament this weekend so it’s been busy here.

This is the y-pipe leaving the primaries, which partly vent to the atmosphere at the moment, lol. Unintentionally, of course.

The y-pipe merges into this pipe that drops down behind the intake horn, just ahead of the master cylinder.

From underneath, you can see that pipe leave the engine bay next to the frame and curve around to the cooler, which is located behind the bumper, just under the stock intercooler.

Here is the cooler. I had to remove the factory filler panels where you would mount fog lights, if equipped, and installed those billet bar panels so there would be some decent airflow. I also used a hole-saw to put holes in the lower skirt for more flow. (Yes, I know the left front axle seal is leaking.)

The air exits the cooler on the passenger side. You can see the check valve and air filter hidden inside the right end of the bumper.

In the right wheel well you can see that pipe continue up into the engine bay.

Then it connects to the manifold turbo inlet from there. The primary boost gauge is located here, as I consider boost at that spot as the “final product”, in terms of post cooling, etc.

I know it seems like a long distance, but when I built this setup I was trying to avoid a lot of sharp bends, which I couldn’t do if it was all kept on the right side of the engine bay. And there’d be no way in hell it would fit with the triples there.

 

[bateman]

Man, I am impressed.

 

[Powerstroke Cowboy]

:banned:

Man, I am impressed.

I agree!! That took time to get it all laid out like that!!

 

[CTD2500]

Thanks! It took an entire winter and quite a few wasted mandrel bends, lol. Luckily it was doable with some trimming of the rad support and fender liners, etc without major cutting or welding.

Luckily I was able to find a couple more pictures, which I didn’t think were on this phone. But here you go.

These are the bumper inserts, with a new bumper too, since the old one was bent to hell.

And this is how the second cooler was added, seen with the bumper removed.

 

[Powerstroke Cowboy]

You made use of all available space it looks like. Took a lot of thought and planning.

 

[CTD2500]

I remembered talking to Tate a few years back while I was in early planning for this triple build. He is/was running triples with HE351 primaries and a 341 manifold turbo. He mentioned his first stage only running 20psi with the wastegates fastened shut, and he ran his 341 wastegate is disconnected from the boost reference, meaning there should be very little bypass through that unit, if any.

This makes me think that my VGT may have the same effect since it has no wastegate at all. Even with the vanes fully open, all exhaust has to pass through that turbine wheel before driving the primaries, so it could simply be driving harder than a wastegated secondary, which may drop first stage boost a bit, either because there is less energy to drive them, or the manifold turbo is moving that air along faster, or a bit of both.

Just thinking out loud about it. It doesn’t look like I’ll have time to fix those leaky welds until I park the truck for the winter anyway, so I won’t see how that affects things until next spring, unfortunately. Maybe until then I can add some more max fuel to see how that drives them.

Hey, remember my tractor? I was finally able to finish up the rear end of the chassis and get it painted this morning.

Before that, however, last week I was testing out some aerosol high build primer on the transmission shifter and the PTO lever to see how it works for filling in rust pits. It’s not bad, actually, but it’s time consuming and uses a lot of primer, which is pretty expensive.

It’s not really thick stuff, but it dries ultra fast so you can just keep layering it on every few minutes. Once you have enough on, you just let it dry fully and sand it down. It did a nice job, and after paint, the shift levers look like new, rather than being full of visible pits.

This shows the levers after many layers of primer. The pits always show, so it’s hard to tell when there’s enough, so I just went with a few extra coats to be sure.

Here are the levers after sanding. You can see the high spots around the pits, and how the primer filled them in.

These pictures are from earlier today, showing first the primer and final paint from different angles.

Here it is unwrapped. The front half is a little dusty, but you get the idea.

It did end up with some pretty bad runs in some areas; it’s tricky hitting some of those flanges and bolt heads from all angles without having the paint pool up and run, (especially on the machined surfaces) but I think most of that stuff is covered when the accessories are reinstalled. I also noticed that the places where I used RTV silicone in place of gaskets behaved weird around the paint, causing runs since it seemed to shed differently than paper gaskets. Again, I think most of that will be hidden so I’m not super concerned about it.

The transmission shift knob is removed in these pictures; it was painted black and is standing by waiting to be installed after the paint dries, along with a new rubber shifter boot.

 

[CTD2500]

Small update here. I just finished installing the new shifter boot and knob on the tractor. Nothing major, but I like how it looks. Also, I’m not sure where I’m going with this project next so I figured I’d post it now.

As for the truck, I raised the max fuel limit and took it for a drive after work yesterday. Total boost was 71psi, with the primaries pushing about 20-21. I didn’t get any drive pressure data, unfortunately; I had removed those gauges for a long camping trip last month and never reinstalled them.

 

[bateman]

Paint looks great. Moving right along.

 

[CTD2500]

Looks like I was able to make some progress today. I meant to clean up the shop and organize a bit, but instead I installed the brakes, plus a few other little things—like the hi/low range shift lever, which I didn’t get a picture of. It’s not much to look at though. Just a lever sticking out of the case.

Here is one of the brake drum installed. Nice and clean with new seals, without a bunch of grime built up behind it.

And here are the shoes and actuator levers installed. This was kind of a pain because the friction material I bought was a bit too thick, so they wouldn’t open wide enough to slide on the drum. I ended up having to grind the material down a bit to make room. Hopefully the brake rods can adjust long enough to attach to the levers, otherwise I’ll have to grind some more off.

I guess next I’ll work on stripping and painting the pedals and the floor panels. I’m still waiting on the machine work for the engine, so that’s at a standstill for the time being. And also I kinda still have to clean the shop.

Oh, and there’s a ton of paint touch up to do with the brush. That kind of stuff drives me crazy, but it’s pretty much impossible to put together painted parts without chipping something, especially painted bolt heads. The nature of the beast, I suppose.

 

[Powerstroke Cowboy]

Looking good! This is how this kind of project should be done. Yes, it takes a lot of time, but it looks so much better though!

Silicone is not able to be painted. It will run off and just flat out not stick.

A little foam roller or foam brush would work good for touch up.

Keep up the good work.