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Got my engine choices narrowed down to 3 options

G

great white

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My 98 is runnin' fine right now (other than excessive blow by :rolleyes5:), but I've been planning out options for the future for a while now.

Here's where I've come to:

1. LB7 swap
pros:
newer drive train, better reliability in the "hard parts"
better aftermarket support
real time tuning with RR and tunercat II/efi live support
up to 6 selectable "tunes"
better powertrain in general
Quieter DI system

Cons:
not and easy swap! lots of mechanical and electrical work....
Down time to do swap
Work and sussing out to integrate with stock systems
Slightly increased overall vehicle weight

2. P400

Pros:
pretty much a "drop in" solution after building an oil pan
Time savings of just order it and drop it in
redesigned block/girdle for better longevity
Replacement parts are still available and much cheaper than Dmax parts

Cons:
limited power ceiling, although annecdotal evidence seems to indicate 500hp is the upper limit. More than enough for me.
Still dealing with limited stock OBDII PCM and management system
Limited aftermarket support
It's still an old design that will eventually run out of spare parts
no real time tuning possible
no switchable tunes possible (yet ;))
Still IDI
Have to make the "right connections" to get one...


Option 1 and 2 have pretty much the same price tag attached to them dollar wise. Duramx might be a tad higher due to need to find a complete donor vehicle, of which some cost may be recovered in selling off what's left of it. Option one also has a significant "hours to complete" price tag also.

which brings us to option 3:


Built 6.5 engine (splayed mians, etc)

pros:
Drop it in in a day solution (once it's built)
Can be built slowly to spread out cost while waiting for the stock 599 in the truck to "give up the ghost"
Parts are relatively cheap for diesel bits

Cons:
limited power ceiling (maybe 300-ish hp)
Still dealing with limited stock OBDII PCM and management system
No real time tuning possible
No switchable tunes
Limited aftermarket support
It's still an old design that will eventually run out of spare parts
Likely to drop it's guts any time just like a stock unit can
Finding a good block is not exactly an easy task
cost will be close to option 1 and 2 once it's all said and done

So, what would you do?

Dmax, P400 or built 6.5?

See anything I missed?

I'm learning heavily towards an LB7....
 
p400 will also need a custom pan. If you do it right I can't see a rebuilt 6.5 (even with splayed mains) costing but about 1/2 of option 1 and 2
 
ak diesel driver said:
p400 will also need a custom pan. If you do it right I can't see a rebuilt 6.5 (even with splayed mains) costing but about 1/2 of option 1 and 2
Click to expand...

Yup, I mentioned the pan.

To build a 65 the way I have in mind, I'm looking at around 6-7 grand.

If lucky enough, I can find an LB7 write off for around that price. couple grand more for bits and pieces minus whatever I can sell off the rest of a write off. So, figure around 7-8 for an LB7 swap.

P400 can be sourced around these parts for about 7 grand. Throw in a couple hundred more for a custom pan (which I can build myself) and you're around 7500-8000.

The prices are comparable. Once you're over 5 grand, I consider the 5-10,000 range as being in the same ballpark...

:)
 
I'm partial to the 6.5, it does alright by me. So if $8K was not a problem I would get a P400 instead of a DMax. But if $5K was a budget then you can build/rebuild/buy a real nice and beefy one to drop in for that.

Even if I got a P400 I would still want to get exhaust manifolds extrude honed, or headers made. The heads too but thats big bucks. If it came as a long block I wonder if it uses head studs or the TTY bolts still.

I think the 6.5 parts will be plentiful for a long time, considering they are still being built new for the military. There is an abundance of 6.2 engines out there, potentially even using GEP 506 6.5 blocks, because military is utilizing the 6.5 P400 now. So in a few years P400s should be showing up in surplus auctions.
 
Hit an Elk and what is the truck worth? Or get it stolen... There is a limit on what you should put into an old truck. You could buy a Duramax equipped truck and put injectors in it by the time you get carried away with a rebuild. After the engine something else will $50 and $100 you to death.

Like door latches. Another front end rebuild... Outside the power train items.
 
I vote for an OPTIMIZER myself. The DURAMAX is nice and all, but it was a royal PITA to swap in(and gets EXPENSIVE much faster than you can blink).
 
I am kind of assuming a P400 is an optimizer that is built with the girdle bottom end? Any other differences between a new GEP engine? Cranks different? Head bolts?
 
buddy said:
I am kind of assuming a P400 is an optimizer that is built with the girdle bottom end? Any other differences between a new GEP engine? Cranks different? Head bolts?
Click to expand...

The OPTIMIZER is just the latest 6.5 design whereas the P400 is a complete redesign of the 6.5 basically.
 
The OPTIMIZER is just the latest 6.5 design whereas the P400 is a complete redesign of the 6.5 basically.
Click to expand...

Then make mine the p400 . OR

Cummins maybe, if comparable in price. Definitely more power potential and even mileage maybe?

I only want to do it once and be able to tow 12.000 lbs. and be 90% reliable.

Being broke has a way of keeping you dreaming thou.

Love my truck,just wish it loved me back.
 
second page seems locked out, need to post to see it....

Cummins is out gents.

Too much weight over the IFS.

Even worse in winter when I through the 7.5 foot fisher plow on.

Even a 'Max is going to add another 150-200 lbs.

The weight consideration alone makes the P400 option attractive.

I don't think I'd go for an Optimizer. If I'm going to drop that type of coin on an IDI, I'll pony up a few thou more and get the biggest and baddest.

I've heard a few rumors that the P400 will produce and hold 500 HP at it's max capacity. That's more than I'll ever need......
 
500HP usually twin turbo marine app's with marine IP and unlimited cooling?

I've never heard of any 6.5 (truck engine) much over 300hp. Not that that isn't plenty, but 500hp seems way to far out of reach, seeing how when every bell and whistle including drugs are thrown in dyno reports barely break 300.

Please elaborate.
 
post to read

The P400 is a very different beast.

Basically, it looks like a 6.5 on the outside and other than being an IDI V8, everything has been reworked inside.

From the heads to the block to the integrated girdle to the forged crank......all different.

will it make 500HP?

Dunno.

But that's the number I've heard thrown around with it in it's center mounted turbo configuration......and that's a MAXIMUM number.
 
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buy a new optimizer or p400, put all new accessories on it (including injection pump and turbo) and have an engine that will last another 300k miles
 
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