At some point in the last post I got rid of my trusty lil Fass 95 and upgraded to a Fuelab pump and a high speed check valve on the return side. Kept a drawstraw in the factory fuel module but bumped it up to 5/8" tubing and ran -10AN lines all the way to the pump. Now fuel pressure was a constant 70psi no matter what.
Called up Weston and told him my goals now that I had a better idea of where I wanted the truck to be at and what I wanted to do with it. Decided on a cast S472/83/1.0, my same 6x.013s with some more needle lift, drilled out edge filters, and a better pump. Was still deciding between a benched 12mm pump or building my current pump into a 13mm, building a pump still scared me some at this point so I kept my eye out.
I was 3 months into owning the 6.7 and completely over it. Was sick of fighting a bunch of little s**t with a daily driver and getting tossed around on these bumpy Michigan roads in a 1 ton on my commute. Didn't really need something this capable when 90% of my driving was to and from work. Decided to lease a Ram 1500 and see how I liked it.
Tax season came around and Jlbayes was still sitting on Don Ms old 13mm pump so I decided I might as well go big and picked it up. Got the pump thrown on after having to learning how to time one again. While setting the idle I experienced my first runaway and promptly threw a frisby on the turbo inlet, intake horn was still off so that did nothing. After some blind scrambling in a smoke filled shop we started cracking injector lines loose and got it to shut off. Luckily Matt was there keeping his cool and knew what to do.
Took a while for the adrenaline to wear off but we got back to it and figured everything out. Took the truck for a test drive and HOLY S**T we had a runner, charger started waking up at 1500 rpm and came on way harder than any setup I've been in before. Cruising at 60mph on a dry road in 3rd gear, tipping into the throttle until I heard a whistle, then matting it would just blow the tires off like no other. This was it, everything I wanted out of the truck performance wise, we finally did it, just a little fine tuning and we can wrap things up then just enjoy it. Took some buddies for a ride the following day, did some boosted launches and pulls, we couldn't believe how this thing ran. Was having too much fun so just one last pull and we'll head back. Locked the truck in 4wd and 2nd gear, brake boosted until I saw about 30psi then let it go. Broke all 4 tires loose for a second then it hooked and planted us in our seats, grabbed 3rd gear and the madness continued until about 3k rpm. The turbo surged hard while I was still on the throttle and the truck started puking black smoke. Slowed down and the truck was idling fine, no leaking fluids. Got back into a bit and it was a little lazy but fine otherwise, tried another pull and even at light throttle the truck wouldn't clean up.
Maybe timing just slipped? I was running a stock gear with a 13mm after all. Bought an adjustable gear slapped it on, set timing the same and the truck still didn't seem to run right. Rechecked timing and changed it either way, same result. During this cluster I found out my DIY gear cover was rubbing on the pump nut and backed that off so I sheared a key. That wasn't enough so 2 bolts backed out of the gear and got lodged in the timing case, there were metal shavings everywhere and at this point I was convinced something was wrong with the engine anyways. Out it comes again to have a good look and clean everything up.
Went back together with the same result. This is weird, maybe something in the pump messed up? Swapped the 215 pump back on and my truck was still a dog but maybe that was compared to the 13mm I was expecting, same exact setup as before. Did a compression test and all cylinders were over 400 but 1 and 6 were 50 psi higher, coolant wasn't pressurizing or going anywhere so it wasn't the head gasket. Valve lash checked out ok too. Threw the 13mm back on, same damn thing.
Didn't want to waste another summer doing nothing so we made a dune trip and were still able to have some fun with it, was just tough to stage at the drag strip. Accidentally got airborne a couple times, almost lawn darted it first run up the hill.
For some reason I still thought it could've been the pump so I swapped on a known good 175 pump, sold the 215 pump to fund the new 13mm build. Thought the turbo could've been a cause so I swapped the GTA4202 back on and went to the track with this 175 pump, couldn't even get the truck to stage with that turbo. Swapped the Borg back on in the pits and went back out. Kept falling under the charger on shifts but I was able to get one more "good" run. 12.4 @ 108 :doh:
While I was at Matts Diesel Supply talking with him about the pump build there was a crusty looking head with a ZZ Fab intake shelf on it, the price was right and I was convinced my head was coming off anyways. He had it sent out to Engineered Diesel to get surfaced and fire ringed. Turned out great, Glenn does some awesome machine work.
Picked up what looks to be a 0 mile rebuilt 160 pump to build the new 13mm out of. Everything was brand new inside.
Matt and I pulled the plugs off the bottom of the pump and found that the cam was beat up in a few places, not good but probably well enough to run. Either way it wasn't going back on like this. Got a reground cam with a little different profile, had the pins and rollers coated, kept my 5k springs in it and decided to start with 131 DVs. Mapped out the pump cam and graphed it, with a little thought and talking with the right people I was able to figure out where to set LPC and why. Put the whole pump together myself with Matt looking over my shoulder and we spent a day at the shop getting it benched, there really isn't as much black magic to these things as most believe.
While it was on the bench we decided to learn a few things. Had 3 different sets of DVs and also some open holders so we put a different combination in each of the 6 plungers hen ran the pump from 11mm of rack all the way up to 21mm rack. Learned a few new things, was pretty cool to have all that info at our disposal.
Put the pump back on and the truck perked up a little bit but it still wasn't what it used to be. There was a dyno event shortly after so I went to see what it would do for fun, pump was pulled all the way back and the truck never really cleaned up. Made 677/1148 on the best run.
When the head came back from machining I got it cleaned up and we threw it on one weekend with Matt. Did a hot torque and took it for a few easy pulls, felt like the truck was back but it was still early. Put a few hundred nice miles on it, was painful to drive the truck nice for that long, then did one last retorque. It rips again! :rockwoot:
Old head had over a dozen cracked valve seats and many of the valve seals were torn up. The tracks were closing soon and I was itching to get that 11s pass again. Spent an evening at Matts shop and we swapped a bunch of different turbos on to see how the truck responded. A cast 75/83/.90, cast 75/83/1.0, cast 80/96/1.10 T4, an Engineered 76/96/1.10 T4, and a cast 80/92/1.0 T4. The 76 ran the hardest but my converter was too tight to spool it, my 72/83/1.0 wasn't too far behind so that went back on. Got home at 6:00 the next morning and went to the track a few hours later. First pass was an 11.695 @ 115, finally the truck was back. Shifted it manually for the next pass 11.438 @ 117.7 :woohoo:. Noticed a bit of oil coming from my janky blowby setup so I called it a day and went home to get some sleep.