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the extra gauge spot could be tranny temp or exhaust temp. i thought about doing the vw tdi but after working on a few vw at the dealership i use to work at i gave up on that, i love your build

 

I don't really think I need a tranny temp or exhaust temp gauge...shouldnt be under anymore stress than stock really or any hotter. And I've never done anything with diesels before but I've already got a few more Cummins swaps in my head for when I get the money together. I don't think I'd go with anything other than Cummins, just for their simplicity, until I have a complete understanding of diesels. And thanks. Body work should start in a couple weeks.

 

Anybody know the best rocker replacement panels?

Always monitor your EGTs in a turbo diesel!!!! Esp with a standard tranny and a motor that is fully mechanical. It's easy to lug a motor in too high of a gear when you should be downshifting. Running rich like that will dump extra fuel down your exhaust system giving you that "cool" black smoke and if you're unlucky, melted pistons.

 

This is doubly true if you are hauling a load, pulling a trailer, or running bigger tires.

 

1050 F should be the max you see with an absolute max (never exceed) of 1100F.

 

Sent from atop the porcelain throne.

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the extra gauge spot could be tranny temp or exhaust temp. i thought about doing the vw tdi but after working on a few vw at the dealership i use to work at i gave up on that, i love your build

 

I don't really think I need a tranny temp or exhaust temp gauge...shouldnt be under anymore stress than stock really or any hotter. And I've never done anything with diesels before but I've already got a few more Cummins swaps in my head for when I get the money together. I don't think I'd go with anything other than Cummins, just for their simplicity, until I have a complete understanding of diesels. And thanks. Body work should start in a couple weeks.

 

Anybody know the best rocker replacement panels?

Always monitor your EGTs in a turbo diesel!!!! Esp with a standard tranny and a motor that is fully mechanical. It's easy to lug a motor in too high of a gear when you should be downshifting. Running rich like that will dump extra fuel down your exhaust system giving you that "cool" black smoke and if you're unlucky, melted pistons.

 

This is doubly true if you are hauling a load, pulling a trailer, or running bigger tires.

 

1050 F should be the max you see with an absolute max (never exceed) of 1100F.

 

Sent from atop the porcelain throne.

I've got an EGT gauge but haven't put it on. Requires drilling into the manifold and then welding a pipe fitting on. Only way I can figure out a probe to fit...
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Yeah, that or tap the cast iron (what I've done in the past). After adjusting the IP on a 6.9 IDI we melted the pistons while pulling a trailer.

 

Turns out if we'd just downshifted and gotten more air flowing through the motor, everything would have been fine. We just didn't know.

 

On second thought, you can also put the pyrometer in the head tube, right behind the turbo. I forget what the temps are there, but I'm sure you could look them up (I'm thinking like 750F max). It's not quite as accurate but I've seen it done.

 

Sent from atop the porcelain throne.

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I have to drill the old "gauge hole" out to fit the probe, then weld a black iron threaded coupler on the manifold so fur probe doesn't bottom out in the manifold.

 

I could put it behind the turbo, which would be easier, but I don't think as accurate.

 

I was driving when I saw your first post, when I got home I the manifold with a temp gun. It read like 380... and turbo was 280-400. Down pipe was 250....

And this was after a hard drive home.

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I have to drill the old "gauge hole" out to fit the probe, then weld a black iron threaded coupler on the manifold so fur probe doesn't bottom out in the manifold.

 

I could put it behind the turbo, which would be easier, but I don't think as accurate.

 

I was driving when I saw your first post, when I got home I the manifold with a temp gun. It read like 380... and turbo was 280-400. Down pipe was 250....

And this was after a hard drive home.

Hard to tell with an IR gun. Even just 15 seconds at idle can drop temperatures drastically, plus you're reading surface temps, not actual gas.

 

I'd advise putting it after the turbo, that way you at least have a way to measure it for now. It's easy to do, and any shavings that fall in just go out the tailpipe. You can even weld the hole up later if you like (not really an option with cast iron).

 

Only other thing I could think of is turning fuel down so you never get black smoke (and high EGRs) but really.... Where's the fun in that?

 

Sent from atop the porcelain throne.

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Putting in after the turbo wouldn't be hard, unbolt the down pipe and drill it and weld the threaded piece on and reinstall...

 

And as for fuel and black smoke...fuel is turned up to not quite half way probably. And not a lot of smoke now. Just when it's lugged down real bad.

She runs good!

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https://vimeo.com/174101231

 

Above is an example of why you need an egt gauge and why an IR gun won't do. My temps are sitting about 600 while cruising in Houston traffic. Coming down a hill they drop to about 550 at the start and as I accelerate up the next one they climb to about 900 (went from 50-60 mph). As I crest the hill I slow to 55 and my temps drop to 600 before I get there.

 

Point being, EGTs are not like radiator temperature with long latency times. It's real easy to lug a motor up the same hill every morning and burn up your pistons in a month or so.

 

Sent from atop the porcelain throne.

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And as for fuel and black smoke...fuel is turned up to not quite half way probably. And not a lot of smoke now. Just when it's lugged down real bad.

She runs good!

The problem is it isn't that simple. You can tune to make a lot of smoke without it getting hot. Or you can tune it so it's very hot but not showing a lot of smoke.

 

I'd put the probe in pre-turbo; accuracy matters. Post-turbo the correlation of measured temperature vs actual EGT is not completely linear and can be affected by a lot of factors that will be unknown in this case.

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And as for fuel and black smoke...fuel is turned up to not quite half way probably. And not a lot of smoke now. Just when it's lugged down real bad.

She runs good!

The problem is it isn't that simple. You can tune to make a lot of smoke without it getting hot. Or you can tune it so it's very hot but not showing a lot of smoke.

 

I'd put the probe in pre-turbo; accuracy matters. Post-turbo the correlation of measured temperature vs actual EGT is not completely linear and can be affected by a lot of factors that will be unknown in this case.

Well said. OP previously stated going pre turbo may be a big hassel at this point so post turbo gives him something as opposed to nothing right now.

 

Either way, an egt gauge is critical on a diesel.

 

Sent from atop the porcelain throne.

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Take the turbo manifold, blast it/clean it. Put it in the oven or even a gas grill and get it hot. Weld chosen bung, also pre-heated, to manifold using stainless or high-silica wire/rod.  Then put the whole shebang in a bucket of sand to control the rate that it cools at.  I've had great success welding cast iron this way.  

Otherwise, the idea to drill and tap the manifold itself will work as long as you find a decently thick enough location.  Usually somewhere right near the flange.

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Take the turbo manifold, blast it/clean it. Put it in the oven or even a gas grill and get it hot. Weld chosen bung, also pre-heated, to manifold using stainless or high-silica wire/rod. Then put the whole shebang in a bucket of sand to control the rate that it cools at. I've had great success welding cast iron this way.

 

Otherwise, the idea to drill and tap the manifold itself will work as long as you find a decently thick enough location. Usually somewhere right near the flange.

Exact way I'd do it.

 

I can't just drill and tap. The probe is too long for the manifold so have to add the bung for depth.

 

Or I'll just go after the turbo for now...

Even though it's been 2 years without a gauge...

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The thing to remember here is that too much fuel heats the piston to the point where it melts.  Black smoke means unburned fuel going out the tail pipe.  More importantly, you still have combustion going on in the hot exhaust gas.  That pushes the temps at the turbo to 1600+ F and the turbo fails like a hand grenade.  Measuring temperature post turbo is not going to tell you anything about getting too hot for the piston or for the turbo.

 

The turbo on my Passat TDI is tapped for an EGT on the hot side of the turbo.  That is where Garrett put the EGT probe port from the factory turbocharger so that the hottest gas entering the turbo is getting measured.

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I'm actually trying to find a 2013+ passat tdi right now!

Good luck with that! Any tdi is a hot item around these parts. I do have a couple friends with them but they're all either waiting for the lawsuit or telling the world to pry it out of their cold dead hands.

 

Sent from atop the porcelain throne.

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Short of moving the radiator back, finding an air-air intercooler that will fit will be difficult.  I would recommend a water to air setup with a larger or multiple heat exchanger to help minimize heat soaking the system.  Just my two cents.

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And I haven't found an intercooler yet that is an easy fit. So that makes this no egt gauge situation even better. Ha.

 

Guys on the TDIClub who are doing diesel truck conversions seem to like a "taco-taco" intercoolers.  Understand the seller goes by the name "taco-taco" on Ebay.

 

I look for a link if you like?

 

Did that chip happen just after I left meeting you Thursday?

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And I haven't found an intercooler yet that is an easy fit. So that makes this no egt gauge situation even better. Ha.

Guys on the TDIClub who are doing diesel truck conversions seem to like a "taco-taco" intercoolers. Understand the seller goes by the name "taco-taco" on Ebay.

 

I look for a link if you like?

 

Did that chip happen just after I left meeting you Thursday?

I'll check them out. Or if you can easily find the link that'll work.

 

 

And no, the crack was from the day before I met you. And it split all the way to the center of the glass before I got home that day.

It's replaced now. $248 for them to come to my work and replace it. Not bad. And they left a little step stool too. So win win.

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