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tnadanzig 09-12-2012 03:19 PM

Jeep OM642 CRD Performance Mod's
I think it’s time we have a thread dedicated to all things performance and improvement modifications for the Jeep OM642 CRD engine. This will be helpful to have all the modifications we have done to improve upon the design, performance, and reliability of the drivetrain in one thread. I am going to start with my rough idea of importance once you buy your CRD. Will reserve several posts to keep this concise and for future improvements. I am going to overlook basic maintenance items because those should be done as per the maintenance schedule available in the owner’s manual. Please post with comments and suggestions.
1st Elephant Hose Mod
Several posts on this mod, I chose a little bit different approach. I used Goodyear 1” heater hose with some PVC hose connectors and stainless hose clamps. I put attached a short piece from the CCV valve to a 90 fitting down the side of the engine a ran along the body seam to the rear of the vehicle to keep any possible amount of gases going into the cab. I ran this setup with my stock intake for a while before I made my intake setup. I machined my own plug for myself and some buddies in town with CRD's. I have a couple extra if anyone wants one $18 shipped.
Routing from valve
90 to go down side of engine
Route down side of engine
Plug I machined
Plug installed

tnadanzig 09-12-2012 03:19 PM

Re: Jeep OM642 CRD Performance Mod's
Reserved 4.7K resistor mod for swirl motor issues. This mod is to jumper out the swirl motor if or before it fails. You need to get a ~ 4.7K ohm resistor in install it in pins red/green and grey. These are the two center pins in the four pin plug. I performed this mod before my swirl motor failed and have not had any problems since and it been several months.
Swirl motor plug

tnadanzig 09-12-2012 03:26 PM

Re: Jeep OM642 CRD Performance Mod's
Tuning. There are several tuning companies out there with good tunes. Custom Spooling, GDE, Inmotion, Stormtech, and others. I don't have experience with them all so I can't really say which ones is better. It depends on what you want as far as tuning and price. I choose Custom Spooling because there were able to provide me with DPF and EGR deletes and economy and performance tunes. They also have the ability to make changes/improvements if needed and they have great customer service.
I have posted before my 1/4 mile times bone stock and just tuning to show improvements. My tune has given me everything that I wanted. I have gained performance, reduce turbo lag, and ~ 2.5 city mpg gain. I have had zero issues with my tune since I have purchased almost a year ago.

tnadanzig 09-12-2012 03:26 PM

Re: Jeep OM642 CRD Performance Mod's
The exhaust system is roughly a 2.75" OD exhaust system with two catalytic converts, one DPF filter, and one pass through resonator at the rear. The biggest restriction is the DPF Filter. This needs to be removed if you really want to unleash the true performance of this engine. I welded up a DPF 3.0” stainless steel delete pipe to replace the filter pipe. It is pretty quick to install and if I ever needed, which I can’t see why, I can reinstall the filter and return the vehicle to stock. I also cut out the resonator and installed a stainless steel 2.75” pipe in its place. The stock resonator weights about 16 lbs. You can get a DPF back exhaust system in 3” or 3.5”, but it’s not needed unless you are going for looks. The stock system flows plenty for any level of performance tune available. With these two items removed the vehicle exhaust note is barely louder at idle with a slight more rumble when accelerating.
DPF Delete
Resonator removed

tnadanzig 09-12-2012 03:27 PM

Re: Jeep OM642 CRD Performance Mod's
One big restriction in the intercooler plumbing is the turbo resonator. It is a kidney bean shaped component with hundreds of perforated holes to reduce noise from the turbo. It really just reduces flow and collects CCV oil. Not seeing many delete options, I came up with a simple delete using 2.5” aluminum tubing and a silicone reducer. I modified the stock turbo pipe to resonator connection for the silicone reducer. Cut the silicone hose going to the intercooler and attached it to the tube. I would like to come up with a more bolt on option. I have noticed reduced turbo lag, quicker turbo boost, and about .3 -.4 mpg improvement in the city. I have not had any problems so far.

tnadanzig 09-12-2012 03:27 PM

Re: Jeep OM642 CRD Performance Mod's
Intake system upgrade, the stock intake system does not leave much in the way for performance. It basically fits the under the plastic engine cover and provides air to the turbo. The plastic engine cover was removed pretty much from day one. To provide fresh cool air to the turbo you need to provide a path from the cool outside air. Cut the air filter tube from behind the grill to pull more cool air and less hot air off the radiator. Upgrade the filter inside the air box to a dry filter element. Remove the stock restricted plastic tube and replace with a 3”aluminium tube with silicone connectors. Notice reduced turbo lag, quicker boost, a little more intake sound, and about .3 mpg improvement.

tnadanzig 09-12-2012 03:28 PM

Re: Jeep OM642 CRD Performance Mod's
Methanol Injection
Running a Devil's Own Progressive Methanol Injection system. I wanted to install the system close to the injection location and I didn't want it inside the vehicle so I decided to mount it on the passenger side behind the bumper. Its a pretty tight fit. I am currently running a temporary 1.5 gal tank, until I can weld up an aluminum tank to fit better and give me more capacity. I inject in a plug I made to fit in the location of the intake silencer. Its after the IAT sensor not ideal, but it works and I won't have to deal with wet bulb issues with injecting so close before the IAT sensor. I will try to come up with something better, but I wanted to get it installed before the oil needed changing so I can get all the build up in this oil right. This way I can have a clean intake with clean oil.
Been running it for a couple of weeks and it works awesome. I currently have the system come on at 16 psi and full at 20 psi. It's very noticeable and you can see the egt temps come down if you do a sustained pull. Need to get some more time adjusting and running different nozzles. I am running a 3 GPH nozzle while I break in the system. I also have a 5 that I will move up to when I want some real power.
Pump installed passenger side
Pump and temporary tank installed
Controller mounted
Motor Shot - injector, wire harness, and fill tube

tnadanzig 09-12-2012 03:28 PM

Re: Jeep OM642 CRD Performance Mod's
Throttle Body Delete
Small update, I have been running the intake throttle without the throttle blade for a couple of weeks. No DTC's and its fun watching AutoEnginuity and seeing the % open value change and knowing there's no blade restriction. Not a very noticeable upgrade with all the other mods, but you can tell it's there. Working on pulling the whole intake throttle and replacing it with a 2.5" aluminum delete pipe. The stock intercooler won't fit a 2.5" silicone connector, it is to small so I had to go to plan B with my delete pipe from some extra material before I use the 90. It has the fitting for the IAT sensor and a 1/8 NPT bung for the water injection system.
Throttle blade removed
Out with the old and the eventual new
Delete pipe - simple design from scrap material

tnadanzig 09-12-2012 03:29 PM

Re: Jeep OM642 CRD Performance Mod's
Received new Intercooler

GNHJEEP 09-19-2012 01:10 AM

Re: Jeep OM642 CRD Performance Mod's
So have you fitted the cooler? I was considering this, 600x300x76? i often sit in my garage looking at the tiny std cooler and think about upgrading it..........

TJcust 09-19-2012 04:44 PM

Re: Jeep OM642 CRD Performance Mod's
Nice thread buddy!

Burner 09-26-2012 11:25 AM

Re: Jeep OM642 CRD Performance Mod's
It's nice to see someone trying to get the most out of our engine. I have an 08 GC and have looked several times for the kidney bung, but I can not locate it at all. I have read that they stopped using it in 08 but I could be wrong or the article was wrong. Is there anything else I would need to change when I go and upgrade the intake pipe? Thanks

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