If anyone has a idit head to look at,i would be interested in knowing the size of the pre combustion chamber slot as compared to the na slot.It appears that the turbo slot is larger from reading.I know gm changed theirs when the 6.5 got a turbo,as well as the military multifuel 6.2s.The slot dimensions determine the expansion rate in the cylinder.I like torque,and the larger slot tends to move the torque down in the power band.However,accelerated wear as compared to a small slot head occurs due to faster expansion rates and harmonics.

 

My understanding is that an 7.3 IDI and IDIT long blocks are basically identical from the outside.
You have a few differences, in different rings, stronger connecting rods and a different oil cooler, but it's relatively minor.

Unless you are pushing 30+ PSI of boost, the differences aren't really important - you can definitely take a NA block and install a turbo on it, or vice-versa.

All the accessories swap over just fine, as everything has the same castings, more or less.

The IDIT heads have Inconel exhaust valves, but honestly:
A. The regular exhaust valves work just fine with a turbo(just watch EGTs) and
B. You can retrofit a NA head with Inconel exhaust valves easily.

The engine balance is different between the turbo and NA flex plate/flywheel, BUT... several people have used the opposite assembly without any issues.

If I was going to build a heavy power build with an IDIT block, I'd have it balanced with a NA flywheel, which would effectively take that out of the equation.

As far as precups and wear... None of the engines I've taken apart have shown wear on the precup. I have seen wear on the corner of the piston opposite the precup, where it obviously got too hot and just melted/wore away perhaps .010" off the corner of the piston... but as far as I can tell, that was more cosmetic than anything. The amount of piston before the first ring is like 1/4" anyway...

 

I read up about these pre combustion chamber engines back in the 80s. Sure wish I could find that book again,I understood the article to mean that the faster expansion with a bigger slot allowed the expansion to take place in a shorter amount of time,(crankshaft angle)which accelerated wear om the rotating ***.

 

One thing that will help the turbo experience a lot is to open up the exhaust elbow on the turbine housing from the stock 2.5" to a full 3". This takes some welding or some money and shipping to Justin at R&D IDI performance. He sells the 3" modded elbows with core return. I did this and it breathes much better, and reaches higher boost. Also unplug the waste gate and max the pump, should get just under 15psi at best and stay out of danger on the Pyro meter due to the 3" elbow. (Will also have to make a better down pipe that actually fits and is also 3", BTW. Still a lot less work than an engine swap and easier with the turbo out of the truck)

Sounds like a fun project!!! Have fun and don't forget to start a thread when you do the work and take pictures!

 

Will do. I refuse to pay what they're asking for a new truck so I will build one. My 2004 Ram has just shy of 500,000 miles now. It's a very nice truck but I am sick of driving it. My hour meter maxed out at 10k hours years ago. My plans are building a driver that I can use for several years for less than 5 or $6,000.

 

when buying parts for the engine, never use 1994 to describe the block.
always refer to it as a 1993, this eliminates most of the powerstroke problems.


another couple of differences, wrist pin and pistons are different than N/A engines


turbo blocks have 1/4" oil ports vs. the 1/8" in N/A.
oil cooler tubes are the only thing that's different, and can use a N/A cooler.

 

These trucks are rare, I keep my eye out for a low mileage one and it is tough...

 

I cant bring myself to buy the newer diesels. I drive the new ones that our company has. I refuse to believe that anything that complicated will not come back to bite you.

 

Plus I have access to all the free clean used oil that I want. It is not used in any equipment with a combustion process so it is very clean. And I have the option to buy crude oil off of my parents for about $0.80 a gallon right now. I ran both in a na 6.2 for years with no issues.

 

As long as it's relatively clean(you might go the extra mile with a 2-micron hydraulic oil filter for your 'fuel'), an IDI'll handle it just fine.
You might need to adjust the timing a bit to get peak performance out of it, depending on thickness/volatility, but that's not a big deal.

 

I have a 55 gallon drum of used oil I was going to get rid of, can I add like a gallon or 2 of used oil to each fill up or do I need a better filter setup to do that ?

 

I never filtered, however I was running military 6 .2s was buying brand new in the crate for $50 each. I bought a whole lot of fuel filters and was changing them about every 6000 miles running unfiltered motor oil. At the time I could get approximately 20 filters for about 50 bucks as well

 

Honestly, if the oil you have was run through an engine, I'd centrifuge it before running it. And then filter it as finely as possible, with a couple of massive magnets on the filter housing.

The problem is the little metal particles which will stick inside the IP, along with eating up the precision parts in the injectors and IP.

 

Well,it appears that my idit engine may turn into a donor engine.I did not know of the many diff between the two.In the automotive world,different can actually mean extra downtime,expense and generally a pita. I think at this time I'm going to pull the entire Turbo System off and put on my normally aspirated engine because I don't want to be caught up looking for special connecting rods special this is special that in case of a failure or major repair.

 

Parts for a IDI T are that are ?, I know RnD can keep them going. Justin told me the IDI T is a good bit better than a reg IDI and can handle HP with out changing to much...