Turboing a 6.9L

[fireman438]

I have an '83 F-250 with the 6.9L, which I am seriously contemplating slapping a turbo setup on. So, since I'm not the kind to go into something new uninformed , I called the local International dealership to get an opinion about such an undertaking, since I figured they would probably have a fairly realistic answer. The answer I got was " I would not recommend turboing the early 6.9's because they have a weak block around the soft plug holes and putting a turbo that engine could cause the block to crack starting at the edge of the holes." The conversation continued for about 20 min. and sometime during that, he also mentioned that to keep an engine with a turbo cool, a turbo-back exhaust should be installed, since keeping the stock exhaust would create excess back pressure, and hence raise engine temp. He tried to seal the deal by telling me he had installed over a hundred on 6.9l Fords when he worked at International on the West Coast, then reiterated about being very careful about putting a turbo on my truck.

What I have seen on this forum especially are a number of 6.9's with a turbo. Is the advice given by the International guy valid, or can I safely turbo my rig and not worry about the block issue?

Any advice would be appreciated. Thanks

P.S I'm new here and new to the IDI Fords, but not new to diesels.

Thanks again,
Richard

 

[towcat]

welcome to the site
couple of questions....
firstly, do you use your block heater? If so, then the soft plug holes is a concern. If you don't, the addition of a turbo makes no difference.
second. miles on the truck? and the amount of blow-by produced at the oil filler cap opening?

 

[fireman438]

thanks for the welcome

no, the block heater is not in use because it leaked after the rebuild approx 100,000 miles ago. i am probably the 3rd owner of the truck, and purchased it about 2 months ago. The truck has about 300,000 in it, but again, the engine was rebuilt about 100,000 miles ago. As for blow-by, I haven't checked that yet. I have still been been in the research and cost phase of my research thus far.

 

[towcat]

For me, the blow-by is the best indicator if the motor will survive a turbo or not. If there is a fair amount, adding a turbo will make it worse.

 

[fireman438]

I'll check the blow-by sometime tomorrow and let you know what i find!

 

[Agnem]

Keep in mind that International themselves, do no recommend turbo'ing these engines. Here is a quote from my research....

Hello Mel,
We are happy to hear that your truck and engine are doing so well. Ford part number E7TZ 6051 BRM is a 6.9L head gasket kit and Ford part number E7TZ 6051 C is a single gasket. The gasket for the Ford application for your vintage is identical to the International application. An International dealer will have a head gasket as part number 1804259C6 (or C7).

I must caution you that your 6.9 L engine block was not designed to support a turbocharger. It would be a shame to have your engine that has lived so long destroyed by a turbo. I don't have specific information to share with you on this but I know we have seen engines in reman that have been damaged beyond repair as a result of turbocharging.

We don't have any sales information in our office on the older vehicles. I will ask my contacts at Ford if they have any access to this information.

Good luck at the next truck show!!

Liz Zid
Service Parts Team
Engine Group
International Truck and Engine Corp.

Calling an International dealer is going to result in a similar CYA response. I can't recall a time here or in the last 10 years of being on these boards where people have put a turbo on and come back with "well that was the worse thing I ever did" or anything like that. That's not to say that you might not end up re-doing your head gaskets, but afterwards your good to go.

 

[icanfixall]

I would install the turbo WITH a boost and pyro gage. If you don't add those gages then don't turbo the motor. These gages will tell you whats going on at all times. The pyro will show what temp the exhaust id at. About 1050 is all you really need to see. Any hotter and you chance melting a piston. If when you install the turbo and you start a head gasket leak just replace them but... Install ARP head studs. Then you wont loose any more head gaskets. Have you thought much about waistegate or non waistegated trubos?

 

[jauguston]

The one issue with a '83 is the head gaskets. The '83-'85 engines had a headgasket design that was a problem for some engines. The gasket was changed for the '86 model. A phone call to tech support at Hypermax will get you a good idea of what they recommend for a '83.

Jim

 

[Agnem]

I can't imagine an 83' on the road with the original head gaskets. It seems an impossibility to me.

 

[Mr_Roboto]

Definitely sounds like "CYA" talk. I don't know why an engine would be "damaged beyond repair" unless it had cylinder pressures / power output significantly beyond the engine's design parameters.

Maybe one of those guys that says "I disconnected my wastegate and have lots of boost now"!

 

[spencnaz]

My counter arguement to those who said the IDI can't be turbo'd goes like this:

"So you mean to tell me that the IDI, with a cylinder pressure of over 450psi, can't handle another 10 pounds of boost?! Haven't you guys heard of the little known engineering concept of safety factor?"

To which all goes silent and order is restored to the universe.

 

[Mr_Roboto]

That 10 psi of boost will add more than 10 psi to the cylinder pressure. Remember that that 10 psi is in the intake manifold, and is then subject to the compression ratio of the engine.

However supercharging a diesel is not so much about increasing cylinder pressures, as improving airflow to supply adequate air to the fuel during acceleration.

 

[towcat]

I can't imagine an 83' on the road with the original head gaskets. It seems an impossibility to me.

+1
even his has been rebuilt 100k ago. Whatever gasket materials was used, had to be more modern.

 

[Diesel JD]

Yes, you will want the turbo boost and pyrometer gauge if you put a turbo on. Also if the exhaust is still stock, there is a need for at least a 3" turbo back exhaust with a free flowing muffler, of course you can go beyond that but that would be minimal. We have determined that most of teh 83-85s with cracked blocks were due to the casting defect by the engine block heater and usually only cracked if the block heater was used. I really don't buy the argument about 86 and later 6.9s being ok with head gaskets. I have heard of quite a few 86 and 87s needing replacement after 150-200K miles and my truck, an '86, N/A had the gaskets fixed at 153,000. Both gaskets were blown. That said, that '83 will most likely have updated head gaskets. When was the motor rebuilt? If it was done right, even that should not be too much of an issue if you watch your boost and egt.

 

[fireman438]

I just checked blow-by and it seems to me that there is very little. I took the cap off of the oil filler tube and put my hand over the hole to try and feel any back pressure because the engine fan kicked up too much wind to watch and too much engine noise (obviously!!) to hear. When I DC'd the shutoff solenoid, a small amount of oil vapor comes out, but disappears immediately on startup, almost as though there were a vacuum (not very likely, though). Also, I checked it cold and while the engine warmed up, and there seemed to be no apparent change. Is there a better way to check blow-by, or is what I did sufficient?