6.5 Optimizer It All Started With A Snap

This is a story about my personal truck.  Its a 1991 Land Rover Defender UK import.  Last Year i decided to take out the old 6.2 GM Diesel i had installed and planed to replace it with a much more powerful 6.5 GM diesel.  After Months of great Performance with the 6.5 diesel it all ended with a Bang as the engine ripped apart a connecting rod.


21222_10205357264362694_8138752098028646241_nHaving found out that the 6.5 Gm Diesel Had Major flaws when it cam to conecting rods and crank shafts i set off to find a better alternative.   I really wanted to keep the 6.5 GM as the engine offered great performance and power and fit my needs perfectly.  I found some information suggested that the 6.5 GM was now made by international Engines in Brazil But they wanted nearly 12 thousand dollar for the long block so i set out to find parts and build my own.  I ended up Finding a used but good 6.5 International block from one place and a set of international p400 Pistons in another.  Next i sourced a set of top of the line upgraded cylander heads, ARP head Studs, Main Support and a set of international p400 Rods.

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Next step was to build the Engine.   I had my machine shop resurface the engine and hone the cylinders to take the new p400 pistons i also had it line bored and the internals fully balanced.  I built the engine using the high side of specs so it could better handle the high operational temperatures i was predicting.

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Next thing to do was lower in the new engine and fire it up!

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    Once i had the engine in i had to head out to recovery a disco2 from a swamp it was a good first run for the beast.  After pulling out the disco i headed to the OVLR birthday party.  The first 500KM were problem free.

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After the first 500KM i decided to strip down the engine and see how it was performing since i was running much greater ETG, Coolant Tempature, and Boost then Factory specs are designed for i thought i would see how it was wearing and see if it was braking is as it should.  I am glad i took the time to do so i found that on half the cylinders that the rings were pushing out as starting to seize do to the extra heat.  I opened up the ring gap buy a extra 7thou of a inch and put it all back together with thicker shim head gaskets to drop the compression even more.  I am glad i opened it up now it should be problem free for the next adventures.

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I hope you enjoyed reading about this build check back for more.


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