Larger Turbo for 6V92TA - Worth it?

[MCI-RICK]

Hello everyone,

I didn't want to high jack the other post on a turbo or an 8V71.   

I've been thinking of a larger turbo for my 1990 6V92TA.  I'm wondering - what else I'd have to do and what would I gain?

Would it help maintain speed on hills or just provide more go power and less fuel economy?

Anyone know the pros and cons?

Thanks

Rick

[luvrbus]

Rick, if you are not getting black smoke on long pulls your turbo is matched for the injectors, a  smaller not larger hot housing will give you more boost pressure hard to tell not knowing what turbo and injectors you have now.       good luck

[MCI-RICK]

How do I determine or find out the injector and turbo size?

BTW, no smoke on long pulls.  If the current injectors and turbo are matched I'll need to replace the injectors too?

Rick

[TomC]

This is a great question for Don Fairchild that knows what hot housing vs injectors you should be using.  You change the hot housing-or the exhaust side- to change the speed of the turbine for more or less boost.  You want just enough boost to keep from seeing any black smoke.  Too much boost, and you'll be wasting fuel to power the turbo.  Don Fairchild-661-391-4520.  Good Luck, TomC

[NJT 5573]

Rick,

By 1990, Detroit had pretty much used the very best turbo on all their engines.

My 89 will accept the download all the way to 450 HP without a turbo change and still meet emissions for a coach. The 450 HP download also does not require an injector change. It still uses the 60 injectors.

The shop that offered me this download told me that it spec's a larger airbox and that the engine could run hot if I did not change it out, but that was the only part they suggested needed attention, the rest is the same.

Fuel is what makes turbos spin, no fuel no boost. So if you want to put your turbo to work, it needs some more fuel.

I have already upgraded to the 350HP coach download, (more fuel), and I am very happy with 350 HP so I may never do the 450. I can pass the trucks at will and out run them when needed, so that's all I feel I need. If I get the 450 HP download one of these days, I'm not going to change the airbox, I will just put a pyrometer on it and drop a gear if it starts to get warm.

The nice thing about having power though is you can usually clear the grade before it gets hot because you don't spend so much time there any longer.

The boat crowd runs these engines at 500 and more HP. They don't last long, but they have to put that power to the prop 100% of the time. Over the road engines only see full power out put on the grades, so the life expectancy really comes up on the highway engines that run some decent horsepower if they are driven skilfully.

If I go to the 450 HP I will increase the oil capacity of the engine by installing a 750 Luberfiner to help keep the oil temps down. More oil takes longer to get hot.

So the answer to your question is the parts are already there, you just need to have a $250 conference with Mr. DDEC.

[MCI-RICK]

NJT 5573,

After a 350hp or 450hp down load will the trans need to be modified/upgraded?  I'll gladly dish out the $250 TO MR. DDEC.  Sounds like a bargain to have the extra power on tap.  I already have an over-sized radiator I'll just need a larger air box.  I'll use the new feature to add this page my bookmarks.  Thanks for the info.

Rick

[luvrbus]

Rick, don't get your hope up too much it is not that simple the 7512 turbo has different a/r's and you may require different injectors one injector does not cover all upgrades.It's the larger air box that confuses me being the air box is the engine.The injectors are 8 number digit not just 60. There is a lot of confusion about the DDEC 2 strokes they are mechanical injected engine not an electronic like the new engines, you get the 6v92 above 350 hp and your troubles have just begun 330 hp was DD's recommended hp for a coach. good luck

[MCI-RICK]

ok guys,

Now you have the new guy a bit confused  Can I get a 350hp download or not?  I don't mind if it involves other minor changes.  Is an injector change complicated/difficult?  A turbo swap doesn't seem like rocket science either.  I'm mechanically inclined (did my share of work on gas big blocks).  I have no experience with DD but there are no "afraidium" particles in my blood.

Can I get some clarification?  Please?  (there, I even included the magic word)  

Rick

P.S.  All jesting aside,  Thanks for all your input guys!!!

[luvrbus]

Rick, if no one has removed it there should be a info tag on the valve cover telling you all about the engine and the components take that info and call a DD dealer.
Customers spec the engine and with all the variations of the DD not to confuse you but a 330 upgrade may not be possible with out changes to the fuel ,air ,cams , pistons and liners .
I am just trying to tell you all upgrades are not possible for a few bucks the injectors for that engine are over 200 bucks each and a turbo can cost you upwards of a 1000 bucks then you have labor cost.
Not knowing what hp rating you have now it is hard to guess you may just be 270 hp range it is hard to find a V692 coach engine above 330 hp.
If you have the right stuff all is good if not forget it and live with what you have.  good luck

[NJT 5573]

Rick,

I just got the 350 HP download. I was shown the part numbers that were needed to run the 350 HP setting in the book as well as the part numbers that go with my engine serial number. They were the same.

I had the 300 HP download, if I'm reading the sales slip right, the 300 download is serial # 06VF173775. My new download/calibration change for 350 HP is Coach, serial #06VF171389. The full DD number is Coach, 8067-7B28-6VF171389.

Its been almost 4 years/85,000 miles running West Coast Mountains since that was done and I have not had any major problems, just pushed out one exhaust manifold gasket that took me a couple of hours to change. When I discussed the 450 HP down load with Courtwright Diesel in Tacoma, they also showed me the parts book and there was a different part # for a part they called the air box, unless I misunderstood something from that conversation. The turbo and injector part numbers were the same.

I have tried to call them to pin call them down on this, (back to the source, those weren't my words), and may need a new phone # or something, but I will keep trying to run this down on the 450 HP down load.

I'm not afraid of the bigger HP settings, I have always hot rodded my diesel engines. There is no thrill like busting the seal on a fuel pump or cheating a computer program... (mechanics that drive are rare, and most just have a book to go by and no real world experiences to draw from, so its always "You can't do this or you can't do that")!

Once you start down that road, its impossible to go back to driving a slow POS. I used to have Marine 115 Injectors in a mechanical 8V92 truck in the 70's, alot of mechanics told me this or that would happen, but it never hung a piston and lasted as long as any of the rest, it just went over the mountain real fast with 80,000 lbs and a little smoke, (just proof that if theres no smoke, theres no fire)! I still don't have any smoke with the 350 HP, so...

My understanding of the DDEC 2 is that the pulse on the injector, (more fuel, and maybe some timing), is changed by DDEC 2 as the HP increases.

Research I have done on the boat engines @ 500 HP + does limit their lives, but I think they figured about 200 engine hours a year would make them due for rebuild in 5 years so the big HP was doable and fairly cost efficient in a twin engine yacht, of course most of those guys have money to burn anyway. Those HP settings also normally run close to the governor with a fixed full load all the time, totally different from running highway miles with an occasional mountain pass to climb.

I wouldn't just give a 450 HP 6V92 to some bed bug hauler that came through the door though, these engines really should have a pretty savy driver that can appreciate the engine and who knows how to drive one to keep it alive.

[DaveG]

Well put Larry.

[MCI-RICK]

IF I could get up to that 350hp mark, I'll take it! (for now).  New I shoulda bought that MC7 with the 8V92TA! haha  Well, I'll work on building up what I have now.  I like my bus!

HightechRedneck (Mike), maybe we can do a piece on a 6V92TA beef-up with before and after data?

Thanks again guys!

Rick

[HighTechRedneck]

That would make for a great article I think.

Before jumping into it though, I would repeat Tom's advice of consulting Don Fairchild.

[MCI-RICK]

Mike,

I'll give him a call and get his thoughts about it.

Rick