Project MIDTRBO

[ALLTRBO]

Well for one that would take a massive leak, but no... Well just let me repost what I posted in the main build thread on PFF...


Sorry the video quality is less than ideal and you might not even be able to see the wheel when viewing on darker monitors. I had to use the mirror because of the location. What the video shows is that the compressor wheel is not moving at idle and starts to spin up a little when revved, but then stops abruptly when it settles back to idle. The thing should be spinning very steadily and easily at idle, and should never, ever, come to an abrupt stop. When spun with my fingers it should go and go and eventually come to a stop progressively. This is how it was when it left here (my wife concurs, I showed it to her and she thought it cool that it spins so precisely, even with just the protective oil).

[Joseph Upson]

If that's a journal bearing turbo and you don't feel any interference with it when turning the shaft it's probably fine. I've seen that behavior before on one of my own turbos where it looked like something was preventing it from turning but it turned out to be a normal response. Depending on your turbine housing size and exhaust temps it may not rotate at idle. I've had both scenarios on the same engine, lean out the exhaust at idle enough and it'll spin fast enough to hear it whistle and other times it might ratchet around until the engine was reved.

[timg]

I've heard of larger, journal bearing turbos not spinning at idle before. Could there be debris in the oil that got onto the journal bearing?

Tim

[ALLTRBO]

Okay, I understand now that it may not spin at idle, I didn't know that (FAIL). Yes it's a journal bearing turbo. However, if you can see the vid, you can see how it slows down and stops really fast. I've never had (or seen) a turbo do that before and it spun freely when I bought it (and sent it off). It does feel like it's dragging a little bit when spinning with my fingers. Contaminated oil is a possibility, but I don't know for sure.

[Joseph Upson]

Okay, I understand now that it may not spin at idle, I didn't know that (FAIL). Yes it's a journal bearing turbo. However, if you can see the vid, you can see how it slows down and stops really fast. I've never had (or seen) a turbo do that before and it spun freely when I bought it (and sent it off). It does feel like it's dragging a little bit when spinning with my fingers. Contaminated oil is a possibility, but I don't know for sure.

If it's freshly rebuilt leave it alone, it should be fine especially since it was okay when you put it on the car. If it doesn't do what it's supposed to do with your foot in it then you have a problem, otherwise unless you know you have a good quantity of fine grain contamination it should be fine.

[1988GTU]

Well for one that would take a massive leak, but no... Well just let me repost what I posted in the main build thread on PFF...


Sorry the video quality is less than ideal and you might not even be able to see the wheel when viewing on darker monitors. I had to use the mirror because of the location. What the video shows is that the compressor wheel is not moving at idle and starts to spin up a little when revved, but then stops abruptly when it settles back to idle. The thing should be spinning very steadily and easily at idle, and should never, ever, come to an abrupt stop. When spun with my fingers it should go and go and eventually come to a stop progressively. This is how it was when it left here (my wife concurs, I showed it to her and she thought it cool that it spins so precisely, even with just the protective oil).

If you have a leak in the exhaust before the turbo, low exhaust temps, and impediments, you will experience that with the turbo. It's not AS bad with bearing type turbochargers, but can still happen.

[ALLTRBO]

Excuse the mostly copy+paste here, I'm busy working on this project. I appreciate the help and comments.

I showed Tim from Tim's Turbos who is the one who built this turbo (it's brand new BTW, not rebuilt) my video and he says yes, sometimes larger turbos for the displacement don't spin at idle. However, he said that it looks like it stops spinning more abruptly than it should, but it may be a few things causing it, not all of which would cause it to need a rebuild. I have some things I need to check out, but gotta do first things first. I'll get back on that one.

Since I'm mostly copy+pasting, might as well mostly copy+paste the pics now, I've been meaning to.
For the full drama that ensued you can go to my main build thread (linked in first post) and read all about it. For this thread, I'll just post up the pics.








































You can't tell from the pic, but the edge that looks blunt is actually razor sharp, I cut myself on it. It's a good thing I wasn't putting my hand down there with my wrist exposed! The upper edge that's nearer in the pic is also sharp.















The brand-new wastegate was supposed to come with its own matching fittings which are a much better design. When I saw that Dave had charged me for wastegate fittings I asked about these, and he said it didn't come with any. I said I wasn't worried about the $10, but he should ask the person he ordered the wastegate from what was up with that because I checked the Tial website and they still show them as being included (as were they with my Talon's identical WG several years back), when he ignored me, I forgot about it until now:











(Note the lock washer):





The muffler, which can be seen between the trunk wall and heat shield, has about 1/4" of clearance to the bottom of the trunk, and carpet is just on the other side of that thin sheetmetal. Instead of asking for the muffler to be as high and far forward as possible, I guess I should have asked for it to be as high and far forward as reasonable. I didn't get a good pic of it, but the downpipe coming off of the turbo has about the same clearance to the trunk wall. That part will glow red when I push it, and there isn't even enough room to put a heat shield in between. A slightly sharper bend would have given that enough clearance to use a good heat shield.



Reverse view of the same thing (muffler clearance):

[ALLTRBO]

Here's looking ahead for the 3200 destroker, I started collecting parts...

Billet crank w/3" stroke
Carrillo Pro-H rods, SBC 5.85" w/2" journals

[TechRod]

Oooh purdy

[Driver_10]

Thats the exact same R.A. combo I was going to use for my stroker (with a 3500 block of course). I thought about using a steel 3500 VVT crank. (Theres no way Id fork up the cash for a billet crank)

BTW... no internal relucutor ring I see.

[ALLTRBO]

The crank was $500 (well I have it in my possession but haven't paid Will for it just yet, still thinking about buying his throttle-per-cylinder intake that is also in my possession, I'll pay for all of it at once if i do). It's used but in very good shape and the journals all spec out perfect so I think that's a great price for it. It came from Ryan Falconer Racing Engines along with a bunch of other 60* racing parts that they didn't have a use for anymore, Will bought a few pallets worth. This was the only crank though.
Right, no reluctor so I'll have to use an external trigger, not a big deal to me.

The VVT 3500 crank was a thought of mine as well, but I didn't want to have to get the rod journals turned down then re-hardened (don't those have a different reluctor wheel as well?). That would have ended up costing more than this billet crank, I think.

[ericjon262]

man, I hate to see you got shafted on the build... got any updates for us?

[ALLTRBO]

Unfortunately, no. Higher priorities have been hitting me left and right (and my health problems slow me down on everything). It really pisses me off that I should be driving this car right now, and I would be if it weren't for an incompetent two-faced jerk.

It's still high on the priority list, but I've got to get through these other life issues first. I would be lying if I said that he didn't take a lot of the fun out of my project, though.

Thanks for the bump.

[Joseph Upson]

The VVT 3500 crank was a thought of mine as well, but I didn't want to have to get the rod journals turned down then re-hardened (don't those have a different reluctor wheel as well?). That would have ended up costing more than this billet crank, I think.

That was a concern of mine as well, but when I inquired about it while planning my offset grind, one of the more if not most experienced machine shops in Tampa said that rehardening the journals would not be necessary. Whether it's because the crank is steel as opposed to cast iron I don't know.

[90BlueZ]

The "Tial" wastegate didnt come with the fittings because its not a real one, looks like a fake cheap chineese crap, 99% sure about that