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Emmott's Initiation

emmott

emmott

Well-Known Member
Messages
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Location
Alberta
I'm leaving the "silent majority" to actually participate in the forums. The 6.5 community here is great, and discussion / knowledge sharing betters every build. I'll post pics of my 6.5TD/GMT400 project work under the appropriate topics so others can provide feedback or get inspired. Disclaimer: I'm Canadian. Expect metric!

I'm a mechanically inclined Civil Engineering Technologist, the GMT400 & 6.5 has been my gateway to DIY diesel mechanics.

My 8+ year DD project is a Burgundy 1997.5 GMC K1500 Ext cab short box with the 6.5 TD. Preventative maintenance and weakest link upgrades on the go since day one.
First motor went when I blew a stock oil hose at 260KKm. I had done the double screw clamp and wire tie mod suggested in TDP Volume I book, but the failure was through the sidewall of the rubber about midway down the hose. Should have just went with braided steel and that's what I go with now.
Second motor was from a '95 GMC 2500LD parts truck. Didn't believe the seller when he said it had a rebuild HMVW block with 80KKm, I didn't know there was a difference at the time or how to check but he accepted my lowball offer.
In March I pulled the second motor at 340KKm after the #6 nylon intake rocker retainer failed. Threw smoke and imbalance DTC. The rings obviously failed in that cylinder. Fresh oil lined the #6 combustion chamber, passenger exhaust manifold, turbine housing, and tailpipe.

Recently discovered the ♦ stamp and "01 18 P" date. Meaning I have a 2008 Optimizer 6500 casting! It also had a girdle, timing gear, and updated DS4. I was going to just buy OEM rebuild kit then put it back together. Now that I know I have a Navistar block I will bomb proof the thing and build a solid highway commuter. Whatever reliable power I can get without blowing a head gasket is what I'll go for. Will likely try propane to get economy and make power if I peak out the DS4.

Here is my build & immediate plans at the time of writing. I'll update my signature line as things progress.

1997.5 K1500 6.5TD Highway Commuter:
Current Mods: '08 Navistar Block, ♦ Precups, DSG girdle, 4" wrapped SS exhaust, HX35W, Vac/EGR delete, F intake/plenum, Walbro + FTB fuel mod, Heath 80HP PCM, Boost/EGT gauges, #9, PMD relocate, Braided steel oil lines, dual alt's, G4D batteries, 4/0 cables, gear reduction starter, bosch glow plugs + PT wire upgrade.
In Progress: Marine 18:1 Pistons, ARP head studs, LB7 Rad + Intercooler + Fan, '00 Balanced Water Pump & Clutch, single T-stat downgrade, Poly Mounts, 1/4" SS riveted rocker retainers w. fat washers (a nylon one failed on me).
Future: Banks OBS Exhaust Manifold + 2.5" Crossover + left header, Exhaust pressure gauge, Heath cam, Steel crank, Gapless 2nd rings, Peninsular intake.
Wishlist: Machined 1-piece bedplate, Ceramic coated chamber & exhaust, Port matching, Marine Injectors.WP_20190716_20_42_17_Pro.jpgWP_20190716_20_41_37_Pro.jpg
 
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Nice! And that picture is hilarious btw.

I would Suggest balancing the lower rotating assembly.
Are you only using the studs on the half girdle or doing studs on all mains? I am doing all mains. Had to reem my non threaded part of the block above the threads so the arp shoulders wont hit. Pretty easy- I was concearned it would be a larger undertaking than it was.

If I could Afford, I would do the roller rockers to ditch the plastic rocker pins, but will just do a bolt method instead to get rid of the stupid plastic rocker retainers. Can you expand on the ones you are doing/ did please?

Are you doing tty head bolts or arp studs? There is a thread here on fixing the leaky coolant issue of studs.
 
haha thanks, the "death cart" has a polaris snowmobile engine so it really rips!

There's a veteran engine machinist in Grande Prairie I'll use for balancing. He's been in the business for 40 years or so. $100/hr shop rate. He cleaned & pressure tested the heads for me, I'm happy with the work so far.

I'm trying to get a quote for a forged crank delivered to Canada, might have to go with cast steel instead. In the meantime I'll get the cylinders bored to match the +.020" marine pistons. But balancing is definitely in the checklist. Got a spare flywheel in case he can't balance with a fluidampr.

Im interested in getting a 1-piece steel alloy bedplate machined, I intend to use main studs everywhere but I don't know the lengths I will need yet (unless I keep the stock caps).
 
When you hit it with a wrench, the pitch is high and it does ring for a bit.. doesn't sound like nodular iron. But the ground narrow lines and rippled surface indicate it's not forged, right?
I asked Quadstar Tuning about cranks and they said "The Optimizer has a cast crank that's pretty much identical to a stock GM crank. The P400 was the only forged crank version and it is no longer being produced as an entire engine assembly.". I'm reading a lot that says otherwise.
WP_20190720_18_50_08_Pro.jpgWP_20190720_18_47_11_Pro.jpgWP_20190720_18_48_01_Pro.jpgWP_20190720_18_49_24_Pro.jpgWP_20190720_18_50_08_Pro.jpgWP_20190720_18_52_23_Pro.jpg
 
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If you get a forged crankshaft, let me know please. Take lots of pics and weigh it compared to your optimizer crank.

Anyone for that matter that has a p400 crankshaft, please do the same. I know a couple of brand new p400 that I worked on, one I helped remove from shipping crate did not have fully forged cranks- only cast nodular.

Afaik, the optimizer crank is nodular.

The Scat crank is cast nodular as well.
I would love to see multiple pics of one again also, been several years since handling one.
 
Welcome to TTS. Looks like a quality build in progress.

Oh, and we are pretty good at encouraging spending money. I would want to coat piston tops with a thermal barrier and underneath with thermal dispersant. Don't think they can balance with Fluidampr.

Seen several posts on the heath cam questioning whether it is really an improvement. ????? I think I would save my money on that and offset the cost of coating pistons. If pistons are being coated then coat something else instead with cam budget ie timing gears or stock cam.
 
@Twisted Steel Performance
Please do.
The two that I saw came from a popular hummer parts supplier And I question if they swapped the cranks.
One broke after being machined dramatically and a replacement crank he bought from a different source looked different. It too was dramatically altered and it is holding up fine to more power than the first.

Dont panic p400 crank owners, this engine is stomping most dmaxs around, and crossing 6,000 rpm mark.

The other one in question is in a build slightly less powerful than Nate’s and holding just fine being beaten regularly.
 
@Will L. , it will be a few days, everything's at the shop being balanced... and a FYI this rotating assembly is really bad, waiting on heavy metal to arrive to finish it... Might have found out why a few P400 cranks have snapped....
 
Les, The lighter pump is a db2 the other one is a p pump.

Chris, No problem on delay for pics, it will be a while before I see him again.

@emmott as well as you sound to be building this and not afraid to drop a couple nickles- consider chryogenics for strength and wear. Do all machine work first, then chryo, then coatings.
 
My plan is to bomb proof the bottom end first, finish all the external upgrades, then do the heads next summer. I'd like to cryo the pistons and block for sure. Hopefully I find a decent quote for a p400 crank & rods, if not I would get a scat crank and cryo that and the rods I already have. I'll take pics.

I'll port the banks manifold then if I'm not happy with my polish job I'll send it for extrude hone and ceramic coat it professionally. I'll aerosol ceramic paint the custom SS left header and crosspipe, wrap with 2000°F header wrap, then DIY aerosol ceramic paint the wrap. I know I could use a van manifold, but the outlet is small, and the NA manifold involves a long crosspipe, and the hummer header is rare and would need modified anyway.

For the new downpipe, I'll go with 4" SS and have an adapter right at the turbine outlet in case I want to swap in a HX40w. The HX35w was a city choice but now I mostly drive twinned highways in northern Alberta. With the 18:1 compression change, ARP studs, and the intercooler, I may need a bigger turbo now. The exhaust pressure gauge will be the proof if it reads way over boost pressure. I'm thinking 18PSI boost at cruise and 25-30 intermittent-max should be safe/reliable for my build.

The heads I currently have were already decked from the previous rebuild, and the precups are all quite cracked, barely within tolerance. I wouldn't want to get new cups and immediately take away metal to match the decked heads. Plus there is a lot of conflicting info on where to get genuine precups. Even though the heads I have passed pressure testing I don't think they are worth new cups, polishing and coating. I'll probably just DIY port the heads to match the intake/exhaust gaskets then buy new heads to do everything right on in a couple years.

Tomorrow I'm dropping off the block to be inspected then bored to fit the +.020" pistons. I'll leave the pistons with him so he can match per cylinder. I'll ask if he can determine weather my crank is cast steel or cast nodular iron. Next step is the gapless rings.

I think I'll hold off on the camshaft regrind until after I get the engine together and running for a while. That way I get a chance to do a dyno before and after. Someone has to be the guinea pig and take a leap on the cam from Washington, there's been too much debate without any numbers to back one side or the other.
 
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