Rick 12v CTD

I have no idea. there's no markings on it to tell, and I was never told.

I also pulled the intake off. There is a bit of in and out play, and quite a bit of side to side play on the turbo, I also have lost a decent amount of oil in a short time. I'm thinking the seal on the turbo is shot too as there is no exterior leaks on the motor. Unless I'm burning oil... I'm thinking the turbo might be the culprit for my issues. Looks like I'll have it rebuilt.

I didn't get to doing another check on my valve lash, or have I cracked the injector lines yet

dB Zac

Sounds like the turbo is the issue

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jimbo486

I would put my bet on the size of the turbine housing being a little too small. You'd know if you were burning oil, you'd see blue smoke out of the exhaust and/or your charge pipes will be oily.

dB Zac

There should be no side to side play and little to no end play

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jimbo486

I wouldn't be so sure of that. Some manufacturers spec axial-play and others spec end-play. You'd wanna see what Borg-Warner calls for.

Rick 12v CTD

I do see blue smoke out the pipe. I always have in the winter, but it's worse than it used to be.

Either way, the turbo is getting yanked and being rebuilt. I'm going to do one thing at a time to see what the issue might be.

Rick 12v CTD

ok just an update on this. It's not the turbo.

Only 2 things left to try are the injectors or cam timing. Unless the 181/210 hamilton cam isn't all it's cracked up to be...

Also, I just did a quick WOT run through 3rd gear (drive) 40mph to closer to 70 or 80 mph. EGTs hit 1500 and were climbing real fast. I didn't see boost, or fuel pressure. trucks kinda fast to be watching the gauges when I need to be watching the road.

I suppose another option for why this turbos manners are so much different than when it was on the 97 motor is that the first gen heads don't flow nearly as much air. Which I have heard, but have never seen totally verified.

Still on the hunt for a set of stock injectors to rule that out... had a few people offer up some non ic injectors, but those wont work. I still do think it's possible my issue is an injector issue that is coming from the spray pattern being too wide at 158*. Wish I had gotten marine pistons to begin with, but it just wasn't in the budget...

jimbo486

I'd have a hard time believing someone telling me that a 1st gen 12v head flows less than a 2nd gen 12v head. It's the same head .

fatt

Exactly the truth. And how are you certain it's not the turbo causing the problem? It sounds like a typical surging issue from too small of an exhaust housing.

Rick 12v CTD

I didn't believe it at first either, because my understanding was that they all flowed almost the same.

And I don't really think it's the turbo because it didn't do it on the other motor. Same turbo. similar power levels. The only difference is the injector pump, and this motor has better air flow (cam, new manifold and turbo blankets) which you would think would help get rid of surging issues, not create them.

The actual rpm the turbo lights hard at, is actually higher on this motor too. and it should be lower. the cam and turbo blankets should make it light sooner, not later.

I think it's possible that the issues I'm having are related to timing and these injectors having a 158* spray angle while not having marine pistons. If I flip my ksb on, the turbo surge is worse, and the truck bucks back and forth. so advancing the timing more makes the problem worse.

I really wish someone would sell me a set of stock injectors for a reasonable price so I could test it out, but everyone is offering non-IC injectors or want $200 for their set of stockers. Which I absolutely will not pay that much money for.

If the problem ends up being related to the injectors I'll be switching to the bosch 7 holes (148* spray angle) or a set of 5x.018s. and selling these 7x.014s with the 7 to 9mm adapters so a non-IC truck can use them. As then the difference in spray is only 3*, not 13*

fatt

You might ask Mark Nixon if he has a set of injectors for you. Have you talked to Hamilton about this at all? I don't see how an air issue (surging/barking) could have anything to do with timing or spray angle, so I would talk to Hamilton about the effects of his cam on your engine. I used to run some 7x12 158* injectors and never had anything like this happen. Also, did you switch to these 7x14 injectors at the same time as the motor rebuild? If so, that might explain why your turbo takes longer to light-you could be "putting out the fire" with too much fuel.

Rick 12v CTD

No I haven't talked to hamilton. Certainly not a bad idea.

And I don't think it's too much fuel. When the valet is shut, it burns way cleaner than I ever expected.

It's real smokey if I open up the valet, and I'm certainly not burning all my fuel then, but it runs nicer with the valet open actually.

and yes, I switched to these injectors at the same time as the rebuild, cam, new IP, etc. And it so happens that the bouncing boost gauge started at the same time as well.

Rick 12v CTD

upon further testing while driving my truck, it seems the only reasonable answer for what my heap is doing is turbo surge like originally suggested.

The cam and turbo blankets have allowed the turbo to spool too early for the amount of air being forced in causing a massive bark/surge under load below about 1750-1800 rpm when I have the valet open. it only flutters with the valet closed because there isn't enoough fuel to push it past that surge point I think.

The cam has allowed the turbo to spool sooner, but hasn't increased the flow enough with the increased duration/lift to compensate for it at that lower rpm. Now I have a motor that lights like a rocket at 1500rpm with the s300 but barks itself so violently by the time I get to 35psi that i not only lose 15-20psi almost instantly, but I bet if I really romped on it and kept my foot in it, it would choke the truck so much that it might even shut off completely. (max psi is over 50 if I have the rpm to sustain the air flow, but it barks really violently as it gets to about 35 at lower rpm)
if I did it many more times I'd grenade the turbo too i bet.

I think the only real answer to stop the surge is to port the head. Maybe some day down the road if I ever have a few thousand to throw at the truck, put a loaded hamilton head on it with bigger valves to let it swallow all that air at low rpm.

it seems hamilton cams do their job, and do it well. the turbo spools WAY sooner than it used to, and spools way quicker and with less throttle. It just allows the turbo to spool too fast and flow more air than the head can put through it.

If you're doing a hamilton cam, get porting too.

The cam is worth the money though.

Overall, I hope this makes sense to someone...

fatt

Or get a bigger exhaust housing. Except you don't know what size the current one is so maybe that won't work.

Rick 12v CTD

true enough.

My thought was to get a bigger turbo anyway, but I'd guess a bigger turbo will just make the problem worse, unless it is simply the ex housing size. some day, I'll be going to a bigger turbo anyway because she gets good and toasty and has a steady thick gray/black out the pipe at wot and full boost.

Maybe swapping turbos will fix the problem, because maybe the housing is too small. Time will tell. It will be quite some time before I have enough money to address any of these things though.