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Optimizer/P400 Engine Parts

W

wyattearp

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Location
McCall, Idaho
So the question of the day is this. In talking with Matt Koenig at Peninsular Diesel, the only things compatible between the Optimizer/P400 engine and the GM 6.5l TD are the external parts. That means that none of the internal parts are compatible between the old GM and newer GEP engines. So if you need internal parts, where do you go?:???:
 
For starters, the Optimzer and P400 are different engines. I don't know about the P400, but between the GM and Optimizer, the internals are interchangeable. Connecting rods, pistons, bearings, lifters, pushrods, rockers, valves, etc.

When I built my optimizer, I had a brand new set of pistons that i put in my 1994 599 block that went into the optimizer without issue. 10K miles later no issues whatsoever.

Someone with more knowledge than me can chime in if I'm wrong.

I don't know about the P400, though. The biggest difference between the GM and Optimizer vs the P400 is the bottom end skirt that has been added for added strength. I wasn't aware that the crank, cam or bore were different, if they even are.
 
nope. the optimizer is the latest casting of the original block with some upgrades (cooling passages, better material). The p400 is a completely redesigned block.
 
when member LastChance was looking at getting one he was told he could get a pan for it from the company he was going to buy it from. Last I heard they were still unavailable
 
In April, Matt Koenig from Peninsular quote me the following prices.

New GEP 6.5 = $6,100
New performance GEP 6.5 = $6,500
P400 = $7,200

These prices do not include fuel system, including injector pump, injectors, fuel lines, return line or a turbo.
 
Supposedly forged crank and 18:1 pistons. As I work on my 85 crew cab, there is a complete 1st gen Cummins 12v available with both injector pump and turbo for $1,350. But in the end to make the Cummins work I need to put in a Dodge radiator, Dodge intercooler, Dodge bellhousing and probably a few other assorted Dodge parts.
 
I don't think the 1st gen Cummins was intercooled. I don't think they intercooled until the 2nd gen (1994, IIRC). The last 1st gen I looked at wasn't intercooled, anyways.

I love my 6.5, but if I'd have had the tools and could have gotten a 12v P-pump Cummins for that low of a price, I would have done it.
 
Your right. The 1st gen motors were not intercooled. I was planning on using a 2nd gen intercooler. I would like to keep my truck all GM. I have this uneasy feeling about using a rebuilt "599" block. I could possibly get a takeout engine for about $2,500. I like the sound of the V-8 diesel.
 
As long as the block is crack-free, you should be OK. The motor in my sig is a take out that i bought from Ted's Trucks 'n Stuffs off the auction site.
 
Thanks. I stand corrected. As much as I don't want to, it would seem that the 6.5 install in my truck would be harder than a Cummins. First is the obvious. The airbox is in the way. Second is that the 6.5 drivers side exhaust manifold conflicts with the slave cylinder. Then there is trying to squeeze in an intercooler. :mad2:
 
I think installing another 6.5 would be much easier than a cummins. Just unbolt everything you can, then pull and replace.

Cummins conversions are far from drop in, turn key. You have to think about moving trans xmembers, adapting your transmission or buying another one, fabbing/buying motor mounts, wiring (OK, that's easy), and having new driveshafts made. Then you have to hope you get a good engine that doesn't blow up on your first trip out. Don't get me wrong, the advantages outweigh the negatives for the conversion, but there is considerable work involved as well.

When you think that a stock Cummins with basically free pump mods can and will lay down more power than a built 6.5, and tow circles around it, the conversion starts to get much more interesting. But, just like any other engine to a gearhead, they are a money pit as well once you start modding them.
 
If my 85 was a complete truck, I would agree with you. However, since this is a frame-off restoration I think in the end a Cummins 12v 1st gen motor is going to go in. The nice thing about these motors is the dynamic advance.
 
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