Charge Air Cooler for 8V92

[65 Don]

Greetings All.  I am new on this forum, Thinking about instaling a Charge Air Cooler on our "93" 40ft coach that has a DDEC 500 8V92.  Has anyone done anything like this, or know someone that has?  I would like to talk about what I have in mind before I get started turning wrenches.  Tnanks,  Don

[luvrbus]

Go for it makes a 8v92 come to life you need to remove the after cooler under the blower and install a deflector very hard to find a factory deflector nowadays and you will also need a different turbo and take time to size it right for the CFM or it will not work it will make it worse btdt 

 Don Fairchild here on the board did TomC 8v71 and Tom loves it,I have friend doing air to air on 8v92 in a Eagle but he dosen't post here

good luck

[TomC]

As Clifford said, I had Don Fairchild plumb up the custom air to air intercooler I had made for infront of my radiator. As luck would have it, my transit had the air conditioning condenser in front of the radiator, so without the over the road A/C, it was relatively easy to have made and installed. Since mine was a non turbo, Don used a Detroit Series 60 12.7 liter turbo with waste gate to keep the boost down to around 15psi (I wish I had turbo pistons to run higher boost-it still smokes some except on a long grade where the turbo gets good an hot).  It works well.

On your 8V-92TA, you already have an aftercooler under your blower.  If you're going with an air to air intercooler (intercooler means a cooler between the turbo and blower.  Aftercooler is after the turbo and blower) I would remover the aftercooler under the blower.  Then just replumb the turbo pressure air to the air to air then back to the blower. I assume the blower already has a bypass valve in it (the bypass valve looks like a small vertical can with a hose at the back top of the blower). The big question is where to position your air to air intercooler?  Then also sizing it to be effective.  Good Luck, TomC

[Cary and Don]

Tom,  Just how much of a difference did it make? 

Don and Cary

[Utahclaimjumper]

 Don,, think of that question a moment,,, from a stock 8V71 to a TURBOed intercooled 8V71,,, don't you think there would be a difference??.. Your 8V92 is ALLREADY TURBOed,, so not nearly as much difference.>>>Dan

[luvrbus]

A big difference in a 8v92 turbo than a 8v71 turbo you can more torque and hp from N/A 8v92 than a turbo 8v71 fwiw  could be you are thinking about 6v92 TA not much difference in those 2 about the same hp and torque

he same

[65 Don]

Thanks all.
  I have a factory S60 CAC that I plan to use. There is room in front of the radiator for the new S60 CAC  (our coach is 102"),  the air tube routing to and from the CAC will not be bad, I do plan to replace the COLD side of the turbo for more bost, and I will have the computer tweaked a little.  The advice that I was looking for is: Should I remove the factory aftercooler, or Should I replace the factory aftercooler with a screen?  I am comfortable with the advice to replace the aftercooler with a diverter,  but have NO IDEA where to look for a diverter. 
  With the new CAC and new cold side on the turbo, will I need bigger injectors?  This question I think will be answered by the experts in Ca. that provide the turbo parts.  Thanks again.   Don

[Geoff]

Personally, I think you should just leave your engine the way it is.  You have a factory designed 500HP DDEC engine.  Any changes you make will only create new problems.  Relax.  Spend your time and money on something else.

--Geoff

[luvrbus]

You will have problems with a CAC from a series 60 on a 500 hp 92 series the series 60 500 hp only require 1170 cfm intake the 500 hp 92 requires 1600 cfm intake you better check the cfm on the CAC

If you planning on getting the boost up to the same as a 60 series the 8v92 will not last at 30 to 35 lbs of boost

Geoff he won't have any problems IF he follows the book they came both ways only difference in the 500hp DDEC and the 525hp DDEC was the CAC and a different turbo  

good luck

[TomC]

You shouldn't use the 12.7 liter turbo-it isn't enough.  If you were to convert the 8V-92TA into 4 stroke liters-it would be more like a 19.35 liter engine.  Hence you need a much bigger air to air intercooler.  If you want to get an idea what your bus would run like with an air to air intercooler, run your bus on a 55 degree day.  That's the type of performance the engine would give you all the time. There is a real good reason virtually every on road engine uses air to air intercooler-they create the coolest intake air temperature which translates into more horsepower from the engine-or better fuel mileage.  With the air to air intercooler on the 8V-92T-it wouldn't surprise me for you to see at least a 1/2 mile to the gallon better.  Good Luck, TomC

[Geoff]

Okay, lets talk horsepower gains versus money spent and expected milage/use of the bus conversion.  I have a stock 350HP 6V92TA and get between 7-8 MPG.  I put around 5,000 miles a year on it (I've had it for 14 years and put around 70,000 miles on it).  I'll stop short of asking anyone what they paid for the horsepower gains for the money and miles driven.  I have tires to pay off now--$4200 on my AMEX.

--Geoff

[sledhead]

Ok probably stirring up the pot . I installed a propane injection unit on my 6v92ta,total cost about $1100. Has been in for 1 year. You can turn it on or off at any time from the drivers seat.My son and I did a test on a controlled route with a hill in the test. Each time I gained an extra gear and lost 10 seconds of the route test with the propane on. We did the test 3 times on and 3 times off, the same each time.It has given me the extra power needed for the up hill runs.I turn it off when not in the hills.I have the regulator set low on the amount of propane injected. The only difference I have noticed is I use a little less oil on a long run.As far as long term use time will tell. At present we only put on about 8-10 k a year.                          dave       

[luvrbus]

The 92 series used 3 different air cooling systems for the turbo engines the air to air has been around since the early 80's the 2 stroke was the first to use CAC all the rest followed DD used the after cooler for space IMO the after cooler is not much good for performance CAC were not used on many buses because of space

You install a CAC on a 8v92 the heating problems drops,the hp and torque goes up in a hurry but we all do it different kinda like we do with ice cream flavors same with propane I never used the setup but have friends that have for years with no problems


good luck

[sledhead]

Geoff  as not to hijack your post I have moved my post to new   thanks   dave

[65 Don]

Well. I have been out-of-pocket, back home now.
  Geoff,  don't think that your surgestion ( if it isn't broke, don't fix it ) hasn't crossed my mind several times, but,,,, we don't full time in our coach, use it for daily transportation, or need to have it to go to work.  Yes, we use it, but to me, it still is a TOY, and some times if my toys aren't brokke, I fix them till they are. With 500HP in an average 42000LB coach I don't need "More Power"  I just want more.  I hope you understand, thank you for your thoughts, everyone's opinion is important to me, they all make me think or re-think my aims in life.
  Right now, I'm not sure where this project is headed, I still want to try a CAC on our 8V92 but need a few more answers before I start turning wrenches
  Luvrbus, where can I get some information on the 525 DDEC 8V92s?  The ones that I didn't even know Detroit made (thought 500 was the bigest HP that Detroit made in the  8V92s).  I realy would like to do some reading.  Thanks  Don