Turboing a 6.9L

[Diesel JD]

Very true Don...that is why I left my CDR connected...I was just going to do a RDT but I felt bad about the amount of blowby....not really all that excessive even with everything plugged up, but enough that it wouldn't go over well here in our "green" town, and I wouldn't have felt great about it. Probably comparable to the Enterprise before Travis blew it up...

 

[fireman438]

Towcat, am I understanding you correctly that a pulse-type turbo is better than a WG setup when the rpm's are up, or do they just not really produce power until the rpm's are up?

Also, the tech guy that I talked to at Hypermax mentioned that a WG setup produces more back pressure, and hence increased EGTs. However, it seems that WG are pretty popular. Any other thoughts?

 

[FordGuy100]

Towcat, am I understanding you correctly that a pulse-type turbo is better than a WG setup when the rpm's are up, or do they just not really produce power until the rpm's are up?

Also, the tech guy that I talked to at Hypermax mentioned that a WG setup produces more back pressure, and hence increased EGTs. However, it seems that WG are pretty popular. Any other thoughts?

Yes, the pulse turbo is better for higher rpm's. They dont produce as much power down low, where a wg turbo would, but up high in the rpm range, say towing on the freeway at 65mph, the pulse would have a better advantage. WG are popular because newer rigs have to meet the epa's standards, and wg turbo offer less turbo lag, meaning when you get on it there is less black smoke and what not.

 

[Agnem]

Correct. Higher backpresure and EGT's are not a concern of the green establishment.

 

[G. Mann]

Blowby, CDR, and other things

Just re-read the thread here. A lot of the discussion has been about gaging the amount of blowby the engine has before mounting a turbo. Early on when I rescued my 85 from the trash [it was a non running basket case due to an idiot savant non diesel "mechanic"] it has HUGE blow by.. at idle when at temp, it would have smoke coming out of the grill even. I took it to my local Ford Stealer and ask them "what's up"? First response was "we don't work on those old engines anymore"... second response was "talk to "joe" he used to work on them".. I talked to "joe" and he said.. "hmm, we used to do a crankcase pressure test, to determine engine condition and acceptable blow by, ..... but the gages and test equipment are long gone... as well as anyone who would remember how to use them"...

Soooooo... seems that at least at one time, Ford and IH had a standard to work to for engine health, at least. FWIW.. I have a full set of the FACTORY MANUALs.. I'll go digging to see if I can find the proceedure and the tool call out.. ,, then we can all go looking on fleabay for an old set of the tools ..

BTW,,, turns out my engine had a ATS turbo on it at one time, it had been taken off and the CDR port was "plugged" with a rolled up shop towel.. no wonder the poor engine was blowing oil out of ever port... I installed a new CDR and guess what... oil loss dropped to "0" .. engine runs clean and stays dry... yeaaaahh Now to install the ATS turbo system I located and get some boost back into the old girl.

 

[jauguston]

The short explanation of the difference would be - If you want to be quickest from stop light to stop light a waste gate turbo will get you there quicker by a small amount. If you want just plain power to pull a load the non-waste gate system will get you more boost, it just takes a few seconds to make boost from a start.

Jim

 

[Mr_Roboto]

Non-wastegate turbos are produced simply because they are cheaper (simpler). Boost will build much slower and max boost will ordinarily be lower. The lower backpressure of the non-wastegate unit is simply a side effect of its lower efficiency (of extracting exhaust gas energy).

From a technical standpoint a non-wastegate would probably be better for a truck that did all its work loaded and on the highway. This would be the scenario in which a non-wastegate would be the most efficient, and a wastegated the least efficient.

 

[jauguston]

Why do you suppose they call them "Waste Gates"? Answer-Because by design they have to "waste" a good portion of the hot exhaust gas you have created in your engine with the fuel you pay dearly for when your engine is working hard. A waste gate simply routes the exhaust gas around the turbo so it won't over speed when you are pulling hard. It is my belief that a waste gate is never efficient, its only purpose is to provide quick low speed power to make the engine drive more like a gas engine. A waste gate system on a gas engine is another whole different animal.

Jim

 

[Agnem]

Non-wastegate turbos are produced simply because they are cheaper (simpler). Boost will build much slower and max boost will ordinarily be lower. The lower backpressure of the non-wastegate unit is simply a side effect of its lower efficiency (of extracting exhaust gas energy)....

Hmm... I'm going to disagree with that. Unlike a wastegated turbo, there is no limit to the amount of boost a non-wastegated turbo can make. I've yet to ever see a truck or tractor built for competition that had a wastegate on it. The reason they are prevelent on over the road vehicles is simply to meet emissions mandates first, and provide more boost at lower RPM's second.

 

[fireman438]

Well, I certainly have a much better idea about the pros and cons of each type of turbo.

Angem: the green establishment? And the comment about pulse turbos making unlimited boost makes sense.

Rich

 

[Michael Fowler]

I know you said the truck was an '83, and that the engine had been rebuilt, and that the truck is new to you ( right on all that?)
I think everyone is assuming that you have the early style block. It may have been changed along the way, and you'd never know. You'd also be worrying about stuff that just doesn'y apply.
The only way to know for sure is to post the serial number. You can find the serial number stamped into a flat area on the left ( driver's side) top of the block.
The number shouls start with " 6.9...." That indicates, interestingly enough a 6.9 liter engine. the serial number follows and ends with a * or similar mark.

Post that number here and someone will tell you for certain which block is in that '83.

 

[6 Nebraska IDIs]

whats the big deal with the blocks?

 

[Michael Fowler]

Sometime ( Mel can no doubt give you the exact date) the 6.9 block was improved, based on early experiece from the field. The core hole used for the block heater tended to crack if the block heater was used. I cannot remember the other early "problems:, but they were all relatively minor. IH made a running change to fix all those early problems. But as Mel's 83 can testify, not all early engines had problems. ( I have a late block for sale in the Markey Place if anyone is interested)

 

[Diesel JD]

Well IIRC the block changes were made in '84 and wound up in later 84 ytucks and most 85s and 86s. Any 83 is going to have the old style block, but I'd not be afraid of it for that reason, especially since you know the vehicle and it isn't cracked now...it probably won't as long as you don't use that block heater or any black warmer in the stock location. The 83s also had slightly different heads which gave a bit lower compression ratio which makes them more suitable for turbocharging. They were known as "A" series 6.9 engines.

 

[fireman438]

Ok, I finally got a chance to look at the # on my engine. It is: 6.9DU2U015878. And yes, it is an '83, engine was rebuilt, and the truck is new to me as of April.

Rich