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O.k.  I have been trying to get acquainted with my 98 12V automatic and I am running across a couple issues that may or may not be related.  First, when I start this thing up, it looks like I am getting blue smoke.  I know if I let it idle for a long time and take off, it looks to be burning oil off of the pistons  (old Detroit terms).  That part goes away when fully warmed up.  Blowby is on the high side for my likes pretty much all of the time.  I need to do an oil change.  It was pretty clean when I picked it up from the dealer, but it could be 3 years old based on the history I got with the truck.  So, then this thing runs what I would call rich.  Seems smoky at idle pretty much most of the time.  Plus, this thing builds EGT's like right now.  In regular stop light to slow traffic, it will get to 800 EGT pretty darn quick and with very little pedal.  Climbing a hill, the truck will make the big shift to overdrive and the EGT will go to 1100/1200 within a few seconds if I don't back out of the throttle and downshift.  I am trying to figure out the setup on this.   Its running a BD Super B turbo, but the turbo really seams like its set for higher RPM.  I can hit 40lbs of boost laying into it on the highway.  But this thing doesn't seem to like low RPM much.  When it shifts into overdrive kind of lazily pulling a hill, it wants to quit pulling, belch black smoke and run EGT's through the roof.  Hit the hill like a bat out of hell and everything sings and sets you back in your seat.  Quite frankly I hate that.  I like to loaf and hang on the torque powering on up the hill.  I know this is a mish mash of stuff but any thoughts on this as far as where to look first would be appreciated.  I have not pulled the fuel plate to see what it is running as of today.  Thanks for your thoughts.  

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I believe a Super B is a 64mm turbo. 

In my opinion, especially with 12v trucks, a 64 isn’t very driver friendly. They have to be driven 15-1600 rpm and above to be responsive at all, and the shift from third to overdrive puts the fire out. Almost every time. 

Personally, I’d put no larger than a 62mm charger on it with an efficient wastewater housing. Tune your fuel to the charger and call it a day. If you need more, run compounds. 

This will help overall drivability greatly. 

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Sounds like you have $$$$$ lots of spending to do to get the truck you want.

 

IMHO high horsepower and towing do not mix well or even mild driving habits and high horsepower in 12 valve auto of the vintage do not mix well .. in my 24 v truck I tried to mix the two horsepower and towing and quickly found that was also the case , they don’t mix well with clean burning rig. I’m running old school turbos ( 40/3B combo) and that didn’t help but the solutions were very $$$$ also . In my defense the knowledge of the day wasn’t as high in turbo selections as today’s and the fix is again $$$$ thrown at the issue or enjoy what ya got lol

some injector change or fuel plate change might help also but at the expense of the HP so the trade off on older platforms is high. 

We suffer from the old designs. The 12 valve being even worse for daily driver/towing with HP as it’s all mechanical , at least the 24 valve can be “tuned” down a bunch by interior switches /  box adjustment 

 

Our lessons are not well received I’m sure but towing is for sure a different animal as to requirements . 

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As Mark said a 62 is much more user friendly with an Automatic.  I have a 63 with an Auto but in a 3rd gen.

 

What you describe about idle smoke is a sign of possible big injectors, so put new ones on your list.  Whatever size you get determines the timing you should get the truck set at.

 

Adjust the fuel plate to your liking.  Doesn't sound like you have boost leaks but always something free to look at.

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4 hours ago, marksmith said:

I believe a Super B is a 64mm turbo. 

In my opinion, especially with 12v trucks, a 64 isn’t very driver friendly. They have to be driven 15-1600 rpm and above to be responsive at all, and the shift from third to overdrive puts the fire out. Almost every time. 

Personally, I’d put no larger than a 62mm charger on it with an efficient wastewater housing. Tune your fuel to the charger and call it a day. If you need more, run compounds. 

This will help overall drivability greatly. 

 

This sounds like EXACTLY what I am experiencing.  I will verify the housing size, but it sounds like I need to switch turbo's...   Anyone interested in a Super B?

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So, at the end of the day I would like to have more horsepower than stock, say 250hp give or take.  Does anyone have a turbo recommendation?  It would seem that I should just go back to a stock turbo.  It is my intent to run this truck through Plateau Diesel as well to have them verify timing, injectors, etc.  Its always a hard call.  Take what you got and spend money until its where you want it, or sell it and try again.  This is close enough to what I want I am leaning towards spending the money, but if you look at my transmission thread, the dollars are gonna add up quick.

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So, I went out to look at turbos and was blown away.  You can get a brand new stock HX35 turbo for $200.  So my question is this.  For what I am going for, is there any benefit to buying turbo for the manual truck instead of the automatic as it should be set for a bit more  boost/horsepower?

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That sounds like a China Knock off turbo, just say no. 

 

As I stated a 62 size turbo is where you should go.  Mike R is at Platue and he knows 12v well.

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250 hp is a walk in the park for the stock hx35 and stock injectors. All it needs is a GSK, boost elbow,  timing, fuel plate. That said, you don't have one anymore, so you may as well enjoy the benefits of a better turbo. Unless you know the stats on your injectors, fresh ones are a great investment in clean power.

 

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Have you considered a DMV search the prior owners , place a call to the last owner  and ask what was done

 

you have many ways to spend $$$ right now trying to get your needs , if you were able to find and talk to previous owner it might save you a ton of cash and narrow down what you have now . 

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4 hours ago, GTroyer said:

Have you considered a DMV search the prior owners , place a call to the last owner  and ask what was done

 

you have many ways to spend $$$ right now trying to get your needs , if you were able to find and talk to previous owner it might save you a ton of cash and narrow down what you have now . 

I have desperately tried to find information about the last owner.  The dealer I bought this from was unable to provide previous owner information and the DMV will not turn the information over to me.  At least that is what I was told.

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On 7/14/2019 at 8:55 AM, Suprmn said:

I have desperately tried to find information about the last owner.  The dealer I bought this from was unable to provide previous owner information and the DMV will not turn the information over to me.  At least that is what I was told.

Did you try having the dealer give the seller your contact? I had the dodge dealer in Idaho do that the previous owner called me we had nice chat. I’m sure you’ve looked sometimes receipts get hidden in owners manual may get the name 

Edited by yogi_160

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I have confirmed that my turbo is a Super B s300gx.   Part # 174430.  Exducer is 64.5mm.  Does anyone know a smaller exhaust housing will bolt on?

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So, its the weirdest darn thing.  Used the truck to tow about 8K a couple of times.  Refueled.  Now, blue smoke at start up gone, and smoke across the board down about 80%.  I am beginning to wonder if I had some bad fuel.  Otherwise, going into Plateau Diesel next week for a check up and some adjusting.

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Early update from Plateau.  Apparently a good portion of the intake manifold to block gasket has been blown out.  No question it was causing the majority of my problems.  Odd that it didnt make any noise that I could hear. Then again, the turbo with the AFE intake is so noisy I probably couldnt tell anyway.

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3 hours ago, livingez_123 said:

How about twins and using the turbo you have now for the big one?

 

Not the best combo in my opinion. Unless your saying to feed that 64 with a 62 then it would work but a lot of money for not that much gain.  Sure there would be no temp issue but not nearly as much HP gain as there could be with another set up. 

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7 hours ago, livingez_123 said:

How about twins and using the turbo you have now for the big one?

I appreciate the suggestion but I like simple so going the twin turbo route isn't for me.  Once I get the truck back from Plateau I will see how it drives.  I had gotten a bit more comfortable learning how to actually drive the turbo so I might be able to live with it as is.  If not, I will go back to a stock turbo and dial the power down to match.

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Ok let's not jump to far back.  Just keep your eye out for a S300 that's a 62.

 

Then you will be able to have useable power.

 

My person guide from other peoples info.

 

2nd gen style trucks 12 or 24v valve =  Auto something in a 62.

                                                                 = Manual something in a 64 or still a 62 if a heavy tower

 

3rd Gen trucks 5.9  Auto 62 or 63 depending on uses

                                  Manual 63 or 64

 

6.7 trucks numbers change and so does the spread.  Depending on uses you can go from 62 all the way to a 66. I'm personally not a fan of a 66 in any application but people do it.

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8 hours ago, C Paul Go said:

Ok let's not jump to far back.  Just keep your eye out for a S300 that's a 62.

 

 

Lol!   Point well taken.  Although, when I get through with this update, thinking might have to change or I might have to mortgage the house for further upgrades.  So, based on the transmission pressure readings, Plateau says the transmission looks to be bone stock.  They were scratching their head and stated that based on the power the truck is putting out, it would easily power right through the 4th gear clutches.  They said as of today, the transmission is operating properly.  The truck has 164K on it, so either the power enhancements happened shortly before the guy sold it, or the trans was rebuilt at some point.  So, I am going to have to be mindful of the trans when towing.  

 

More on the engine.  The truck has aftermarket injectors.  They have not identified what they are but stated that they are not stock.  Fuel pressure to the injector pump is way low.  They are going through all of the usual culprits working on that part.  It appears that the fulcrum lever is getting stuck below the fuel plate.  Also, the truck is suffering from a low RPM miss.  They are going to fix the fuel pressure, fulcrum lever and check the governor springs.  I am having them adjust the valves as well.

 

Plateau is pretty confident that they can make the truck run like I want with the current turbo.  I told them I am open to discussion about swapping out the turbo, but they said they think I will be happy with their outcome.

 

I will say that I am reasonably impressed with Plateau so far.  I have a very detailed print out of all our conversations, their work and their recommendations.  For me the proof is in the results so we will see, but I am hopeful.

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There is no way that transmission is bone stock if the truck have more than 300 hp.

Sent from my SM-G950U using Tapatalk

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There are some rock solid guys there including my cousin but he normally gets the Duramax's.

Sent from my SM-G950U using Tapatalk

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o.k., picked the truck up from Plateau on Friday and its a completely different drive now.  Took a lift pump to get the fuel pressure right.  And, while I am thinking it about it, be careful of any overflow valves purchased from LarryB.  The one I bought had the right part number, but wrong overflow valve.  I had bought it some time ago and they were nice enough to use my part.  Cost me some diagnosis time for them to realize the valve was incorrect.  The big issues were the blown out intake gasket, very low fuel pressure to the pump, and the fuel plate in the truck was set to make power at the top end of throttle.  No number on the old plate so I am not sure what it is.  They put in a #10 plate and things are much better.  Truck now makes power much quicker, and picks the turbo up much quicker as well.  I am quick happy with the results so far.  We will see how it goes the next time I tow.

 

So, the one issue that I am left with is something they call a fishbite miss.  Right about 1400 RPM, when I give it light throttle it will miss.  At first I thought it was a bad ujoint the way it behaved.  I am convinced the truck sat for a long time.  I am going to run some concentrated fuel cleaner in and make sure I don't have a sticking delivery valve.  If anyone has another direction they can point me on this, please let me know.   Thanks.

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Well, still too much smoke and I have a miss at around 1500rpm in overdrive that is driving me nuts.  I have a set of DDP Stage 1 injectors coming from Rip and the truck is going back to Plateau to have the timing checked and some more diagnosis.  Hopefully this round will cure whats left.

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It is amazing just how hard you can get slammed down when you break one of your basic rules.  I have had a general rule to never buy a modified vehicle.  I have bent the rule on a couple of occasions, but for the most part things I buy are stock and then I mod them how I want.  Well, here recently I have put caution aside and have got my ass kicked.  My 98 12v has been a disaster moneywise.  I stopped by Plateau to get an update on my truck.  Injectors are in.  Timing was set by the previous owner at 20 degree.  Now set at 16.  The DDP stage 1s are in and smoke waaay less.  Valves are adjusted and several of the exhaust valves were tight.  So, at this point its running better than ever since I bought it.  Except for the miss.  it misses between 1300 and 1600 rpm.  drives me nuts when cruising, even worse when towing.  Soooo, the official word is that its the fuel pump.  So, its coming off and going to seattle injector.   Hopefully this cures all and I can have some run time with out spending money.  By the time I get it back I will have spent $8000 over and above purchase price.  Not happy.....   Nooooot happy....   Ever wish you could go back in time and slap yourself in the face before you say.....   I'll take it....

Edited by Suprmn

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