2009 GEP 6.5 swap

[TrenchFoot]

Why the different crossover? Was it for clearance to fit the OBA? I'm looking for a different crossover because I have the stepvan version with a thermostat housing that points up and will interfere with the hood.

I was just planning on the more common truck style from a 6.2. Curious why you chose that one from a 6.5, single tstat.

[BA_051]

I'll have to get some more pics of the whole truck uploaded and posted at some point. Just been real busy working 2 jobs for the time being.

I actually still have the 6.2 crossover with thermostat that I removed when I installed this one. I went with the 92-96 6.5 single tstat over the dual because of clearance issues with the db2 pump, but yes, it was for clearance for the York to fit where the factory AC compressor would. I didn't feel like having to rework the throttle cable around the tstat housing as well. It's coming together slowly but surely.

Next fix will be the front seal on my 205... don't know why that's leaking... leaving that for the spring...

[BA_051]

Ok well I finally had some time to download my pics from photobucket... i HATE that site now, way to many adds and lag... Now I'm using google photos... So much better.... slowly but surely making my pictures visible to all again

[BA_051]

Well it has been almost 2 years since I swapped in the NA 6.5. Long story short, I picked up the F code upper and lower intake manifold, the oil feed and return lines, both exhaust manifolds and a new crossover pipe for $300 in August 2016 along with an HX35 (a lot of people recommended it on various forums) and did a 4" strait exhaust from the turbo all the way back. I adjusted the fuel screw so it barely touches 17-18 psi boost at 2400 rpm at WOT and it rarely smokes (only if RPM's are lower than 1250-1300 and I'm laying on the gas). It really, really woke it up.

In September, My family and I moved from NM to WA and I weighed in at 14,000 lbs and it performed admirably despite it had the military NA coolant crossover and no fan shroud and it still maintained 13-14 mpg's. It now has a fiberglass fan shroud (that I made) and the bypass blocking Tstat crossover from the 1992-1995 6.5TD's.

This summer, I am planning the next 'upgrade' which will eliminate that factory super restrictive passenger side manifold and either do 1 of 2 things. I will either try and fit the van/centermount turbo log manifolds and move my turbo to be similar to a center mount but not be an actual centermount, Or 2, use the shops waterjet and create my own exhaust flanges and use 1.625" tube and run them (all 8) behind the motor into a single 4x2 row collector to either a T3 or T4 flange... Option 2 is a lot more fab but if i cant get the factory manifolds to fit, then i will have to it that way. In either case, the restrictive exhaust manifolds will be gone and it will breathe easier... Which leads to my second 'upgrade'... Ditching the HX35 for an HE351.... Based on the boost profiles, its quite a bit more efficient and its a single scroll vs twin scroll. My HX35 is 54/58/12 and the HE351 is 60/60/9 so the the compressor and turbines are larger, but the turbine housing is smaller... I will keep you updated as I progress through this project...

I am even considering creating a 7.4L stroker (449ci), but the $9-10k is way out of budget right now... If your curious, I would use a P400 block/girdle/oil pan ($3000), International 6.9 0.060" over pistons (drop in, $800), rebushed rods ($150 shop quote), and a custom billet crank from Scat with a 4.15" stroke ($5000 at least quote from Scat). It would also drop the compression down to 18.6:1 making it perfect for 30lbs of boost.... That would be a really mean motor.....but a 12/24v cummins would cost less even with a rebuild...

[Mikel]

[BA_051]

Ok, so I purchased various parts to put together a modified HE351... Here are some pics.... It started as parts from various sellers for dirt cheap... Compressor housing was $25... turbo cartridge was $100 and the turbine housing was $250 with the new turbine/shaft and $50 for a complete rebuild kit. Then it was about another $50 for vbands and flanges, ect.. So not in all a budget breaker!

I cut off that area where the boost controller bolts into, had it sandblasted, then powder coated at work and finally drilled and tapped the hole to 1/8NPT for an elbow to the WG diaphragm... I may just make it regulate from drive pressure with a spring, but haven't decided yet.

The specs:
Turbine: 67mmx76mm HX40 turbine (stock is 58mmx65mm)
Compressor: stock 60mmx85mm

So its pretty much a super HX40, but with a single scroll and smaller housing than the HX35. This combo should drop my drive pressure and EGT's, and spool wicked fast...

[BA_051]

I have ordered a set of new GEP centermount/hmmwv exhaust manifolds but haven't received them yet... I also got the flush mount oil pump drive so i can get rid of that cam position sensor thats used for the 4L80E that was used behind this motor. That will allow me to use that huge area to plumb the exhaust and put the turbo back there... I may even make a cowl hood too to supply fresh air to the area... or just plumb a cold air intake... so many options... Just Empty Every Pocket....

[BA_051]

Well, Im not sure what happened, but I just drained about 2 quarts of coolant out of my crankcase... And yes, its a genuine GEP 6500 Optimizer, not a GM or Chinese POS...

It starts great, idles great hot and cold, no white smoke hot or cold, no coolant smell in exhaust, no heavy blowby, no symptoms at all, none, except I lost almost a gallon of coolant in 15 miles... most of it ended up in the oil... hell oil pressure stayed in the 35psi range hot idle off the highway and 65+ while driving at 1800-1900 rpm...

If i wasnt paying attention to my temp guage (it was running about 192-195, which it has always stuck at 180ish with ambients in the 40-50 degree range) I would have missed it and kept using it....They seem to run a little hot when coolant gets low...

So i guess its time to tear it out and down, with no air tools, no engine stand or hoist, nothing but hand tools... It really sucks moving 1400 miles and leaving most your stuff behind because of lack of room....

[BA_051]

So after 2 hours of diagnosis, my 6.5 has a cracked block... Yep, a cracked block on a genuine 6500 optimizer... The #4 main web cracked and moved up into the #6 and #8 cylinder water jackets... So this hing is toast...

So now I am on the hunt for one of 2 motors... a P400 shortblock (preferred for ease of install) or a 12 or 24v cummins....

[BA_051]

Well no go on the P400 shortblock, only longblocks, and can only be had new... At $7200 for a new P400 longblock, I guess it?s time to look for something else... on the hunt for a mechanical 5.9 to swap in...

I know GEP is working on a direct injection version of the P400, but that can be many years down the road if it even makes it past testing...

[Mikel]

That sucks. Try www.car-part.com for finding an engine (or any other used components)

[BA_051]

I got in contact with a small wrecking yard in the Dallas area and have a 1996 12v on the way... Has 150k miles on it, they took a video of it starting and running and it has no blowby and good oil pressure. Just need to get a bellhousing, clutch kit, and new input shaft for my NV4500... I called Valair and for about $800, I will get a 13" upgraded clutch/flywheel, and 1 3/8" upgraded input shaft. Not a bad price at all! I will start a new build thread when I start the 12v swap.

Still a couple weeks out before I start the swap, but if anyone is interested in 6.5 parts, let me know...