Big book response warning!!!
Besides not seeing the main web cracks you guys know to look for, here is why I know it is so different.
Not seeing the cylinder wall split- which is super appearant on center mount turbos in rear number 8 where the hmmwvs still use the 4 bolt waterpump and routinely run high ect temps. They wipe out the rings from it, and talking to couple different guys in the motor pools- on sample engine tear downs, the rings are newr gone and some piston scuffing occurs on #8 to the point of temporary engine sieze is possible. This is exactly what was going on with all the cracked block gm castings except the optimizer blocks are handling it with out failure- but the blocks failed before the piston got squished in place.
The sucess rate of the GEP optimizer in hmmwvs compared to GM castings was perfect. It all but eliminated all the blown engines the hmmwvs were experiencing. The only reason they went to the p400 was that hmmwv weight and load rating doubled. Most up armoured hmmwvs drive around at 18,000 lbs. Compare that to a normal slantback at 8,800 lbs. with all the added weight they would not accelerate any faster than grandma in her wheel chair.
When Gale Banks got involved, he started building them kits that was 450hp and 700 torque. Then they started having rod failure, not block failure. With the long known history of the mains blowing out, he worked with the GEP engineers and educated them about all the mods done in modern racing engines. Then they designed the p400. I talked to him about trying to get them to do the 2 waterpump system we figured out that led to the balanced flow pump. GEP/ AM General lawyes squashed that as too similar to GM's new pump.
When they did the banks hmmwv demonstration compared to the stock one at 29 Palms- they told the overheating story. I got up to talk about the circulitory issue, and my hoodscoop design, and why they should skip it and focus on stack redeisgn. I would imagine if you search the web you can find the video of it around still. (If so, post a copy please). I am sitting in the second row on the right hand bleachers all the way to the right with my leg hanging off when the camera pans while he is taking questions- me in a suit- haha. I did see Gales talk posted years ago, not mine- I guess I'm not as cool as him- HAHA, DUH! It didn't make the video that I saw, but in the q&a session, the failure rate of the optimizer was brought up.
They made it abundantly clear, they were having almost no failures, but only doing the "high performance engine" (p400) on the fully up armoured hmmwvs. That is why they are still producing the optimizer today. If it were a failure and the p400 was a fix for it, they would have stopped the optimizer and only started making the p400. His complete package fixing steering and handling issues made it too expensive to swallow. If he had done an engine package and put in the handling pakage with it, they would be using his complete system.
So do I think it is a failure proof engine- of course not. But the ability to withstand what we accept as "too hot" (220 and above) while the military is out there telling guys- "it is only 240, keep going" and not having the cylinder wall split open on #8 should explain alot. The added heat and stress in hummers is so bad to the #8 that if you read on the hummer forum - they just call them "at risk blocks" or say "I had #8" and everyone knows what they are talking about. Hummer dealerships literally sent someone out to every single hummer owners house that did not respond to the letters over the overheating issues trying to deal with the problem(kinda).
In pickups, the side mounted turbo keeps enough extra heat away from the head that they can generally survive better. But even then- I have called it on a couple of engines on this forum for "look at #8 first" to be asked -how did you know- once the engine got opened up.
Seeing the rods have bent and smaked the bottom of the cylinders is nothing new for any 6.5. Most all of us have seen the s shaped rods at least once.- you, me, WarWagon,consaka, Bill Heath on the flats once iirc at 140-all come to mid quickly- more have to be on here... But it just depends which way the metal bends.
The fact that optimizers still bend rods and can hit there isn't sign of the block being bad.
All the Mercedes idi- 5 and 6 cylinder that have the same high compression and higher rpm running engines like us bend their rods into s shape also. Just bieng inline instead of v design thiers hits other areas, usually piston skirt to crank.
I have never cut a chunk out of parts and sent them in, but I have put magnets to them and could feel a difference in the holding power- just a hillbilly test on the metalurgy I was explaining to my son learning about magnetism in different metals for science class. Something is noteably different doing that- and why would GEP lie about using an exact match to the original Detroit engineered spec that GM pinched pennies on? GEP was not planning on selling them to the public- only to their 1 customer- themselves- AM General.
They even fought in court to not have to sell to the open public at first. Who were they to marketing to?
They were releasing the info they were required to because of going from publicly traded company (GM) to a sole source - originally AM General was to be the name on it. GEP company had to be created as a seperate entity for legal reasons mandated by military sales contracts since AM General wanted to stop using the outsourced GM engine. There are a ton of parts AM General would not sell to the public (hummer owners) until the forced creation of GEP- General (as in AM General) Engine Products - a subsidiary of AM General...
AM General needed a solution to the cracked blocks problems plaguing the hmmwvs. They were worried about hmmwv replacement coming sooner because of it. There was lawsuits over the balanced flow waterpump (pretty sure I mentioned those before here). I got pulled into it becasue of the testing I did with/for GM when I worked for Rebel/Unical/American Truck. We did all the flow testing. I am the one that cut the side out of a block and mated the bullet proof glass to the side to watch the coolant flow issues on the cylinders. It was my 12v waterpumps we used for the 2 separate pumps to see the flow volume 1 side at a time. (Why I shake my head when people still think balanced flow waterpump is no biggie or worse try to credit Bill Heath with it.)
Still today hmmwvs use the bolt on waterpump with its uneven flow because the lawsuit issue of GM having "corrected the overheating issue" that they thought would stop AM General from being allowed to make their own 6.5 liter engine. AM General cant use the balanced flow waterpump until the year 2018 (? iirc). I doubt they will bother with the sucess the optimizer 6500 (they are not allowed to call it a 6.5 liter, they have to call it the 6500 kl {kiloliter} or just optimizer 6500- again legal issue).
The ruling came out that GM knowingly defrauded AM General and as compensation they could, under a seperate company (GEP) produce and sell an exact copy or any modified version of it, without royalties to GM. But in AM General not accepting they "fix" of the balanced flow waterpump, they are not even allowed to use it on their products for 20 years from the lawsuit date. That was a countersuit filed by GM. The same one that mandated the "injured name" of GM 6.5 should be able to force GEP to have to sell to anyone, including the public, the engine. Which is why you cant buy only a block or only a single piston. The court set what parts they had to openly sell.
GEP has to sell at the same price they sell to AM General, and in paying order- thats why you cant buy a p400 option 6500 optimizer right now, they have another customer that put in and paid for a certian number of engines, AM General. Once the order is filled, then Leroy and others can get their name back on the list. - I bet Leroy has at least 2 people offering him cash right now for new p400 that he cant get from GEP because of it.