Building a 7.3 HotShot motor

So with the engine out I disassembled it and started checking things as I went. I didn't find a whole lot until I started measuring the clearances. Upon pulling the pistons I found that all the top ring groove clearances were way out. I couldn't find a spec but .055-.085" top ring groove clearance has got to be out of spec. Then on pistons 7 and 8 the top and second rings were broken. Surprisingly or luckily no cylinder scoring was evident at all. Dodged that bullet.... So, it was evident that this engine suffered one heck of an overheat to sustain that much damage. Being a Powdered metal Rod engine I checked the rods for damage and straightness. They all seemed to be OK. So on to the cylinder head strip down. I pulled a couple of intake valves and they looked pretty rough. Then I pulled the injector cups and found some more evidence of the overheat damage. The coolant passages were sure enough cracked in the intakes of both cylinder 7 and 8. I posted a question on here to see if everybody agreed with me that these cylinder heads were very heavy paper weights. We all agreed so now it was time to search for some 7.3 heads that weren't a small fortune. I found a set down in Biloxi Ms, for hundred dollars each. So a road trip with my RiffRaff injector cup puller and I was off. They both checked good so we were on the way. So once home I stripped them and checked them for any other damage. They looked pretty good except for valve wear. The intakes on these 7.3 engines seem to get pretty beat up over time.

So here is my build: I'm going after 450-500HP, no smoke and longevity. The first change was to go to forged rods. I managed to pick up a set of good rods and also picked up some ARP rod bolts to go with them. The crank was straight and did not need ground so that was just a set of new bearings and polishing. Because a set of different rods is now in play I had the assembly balanced. With the amount of torque and HP output this engine will create, a dual disk South bend clutch was chosen and the South Bend flywheel was included in the new balance. I also chose to utilize main studs from ARP as well. For the new pistons I chose Mahle reduced compression pistons with rings at +.020". So the Bottom end parts choice was pretty straight forward.

The top end was another story altogether. My machinist let me know that the heads would need cut .005" and new intake seats would need to be installed. I had decided to buy new OEM valves so one of many orders to come was placed to RiffRaff. I decided to go with CompCams 910 springs set at 1.78" height. That will yield about 125lbs of seat pressure. Smith brothers stage three push rods will be installed with new Ford lifters. I found a trick to getting lifters at a decent price. The same lifters were used from the 7.3idi to the 6.4. So ordering part number 8C3Z-6C329-B is a set of four lifters for a 6.4 at the cost of $58.03. A set of 16 lifters comes out to be $232.12 as compared to Ford 7.3 lifters at $35 each or $560 per set for the same lifter. I chose not to use Mahle lifters as they seem to be a bit lacking in durability. My machinist did all the seat replacements with new guides and a three angle valve job. I will be setting the new springs in with new keepers.

The fuel system is where big money seems to migrate. After talking with a bunch of vendors about the end use of the truck and the desired longevity I decided on FullForce 205cc 30% injectors, a Jelibuilt tuned Hydra, and a T4 turbo kit with a S364.5 Turbo and .91 housing. These will be driven by an Adrenaline HPOP and a full regulated return fuel system. Exhaust will be a stainless four inch Diamondeye kit. Of course this took all kinds of research and tons of emails and phone calls to come to this build level. There are also tons of small parts and "other items" needed to get this all tied together. I 'll be starting the assembly next weekend as I just got the block and the balanced reciprocating assembly back from my machinist this past week.

I did get some powder coating done on a bunch of miscellaneous stuff that turned out pretty well.

PDR60 said:

That's correct. What I'm documenting at this time is just the engine and periferals. The rest of the truck will be dealt with after the engine is back in and broken in. I've done a couple of ZF transmissions, they aren't too bad. The rear end will just get a freshening up with all new bearings and seals. Then there is brakes, and suspension. By the time I'm done she should be better than new and able to run well.

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Don't want to sound rude but here it is...

The 7.3l is the wrong platform to start hotshoting unless you get some super magic luck and find dedicated routes with reasonable loads. Plenty of the 2014 rams being ran have over 500k miles on them using tandem axel, single tire 25-35ft gooseneck flatbeds. As a new entrant your insurance alone is going be $750 plus through progressive for just one truck and one trailer. You'll be burning so much fuel you'll not have much time for any repairs with a 20 yr old truck. Can it be done with a 7.3l? Yes should it be done no. You'll be competing for everything as a new truck and you'll be forced to take all the lower paying freight and the 7.3l will just not be as comfortable, fuel efficient, and reliable due to its age. Not that a emissions running truck doesn't have its problems but just feel you should really reach out to others in your area who are doing it before you put all this time and money into a truck that don't get me wrong I love my 7.3l, just would never hot shot with it in a million years after all the success of a different platform.

The 7.3l engine is amazing but you drive 500k miles in 6 yrs with a 7.3l vs the newer and softer riding and stronger suspension, quitter, more powerful engine your body and bank account will tell you the difference. ps multiple trucks with 500k or more miles all 2014 or newer.... There is just too much completion out there cutting cost and corners for anyone to make a profit with out having some luck, $$$, and networking etc.

Just something to consider if you truly want to start hotshoting etc.

Jeff-F350 said:

After many many years - decades - in business... I found its best to just keep your mouth shut about what you are about to do and why, and just go do it. Right, wrong, or indifferent. If it’s what you want, just go do it. You’ll learn and you’ll adjust.

I’ve heard every reason why not to do something.

Justin is not playing nice today. Which I actually find unusual for his posts...

Enjoy! Keep up the build thread.


Watch this video. Over a million miles hotshoting on his 7.3, and still going. Happy trails PDR60!

https://m.youtube.com/watch?v=kNHax-CHSEs

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Thanks for the reply. I've seen that video, great stuff. I kind of figured I might get the negative response from someone eventually. Justin is certainly entitled to his opinion and I take it and evaluate it against my goals. I've worked hard all my life, some physically demanding jobs and some more mentally demanding. In the end its planning and preperation that makes the difference. Apparently completely rebuilding and renewing an older vehicle just doesn't measure up to a $65k new model that will need even more expensive maintenance within 2 years. One of my careers was deep cycle refrigeration. I drove my service truck, a 92 f350 over 750k miles in 6 years. I worked in almost every state in the lower 48. It was fun and challenging. That 460 was never cracked open and I did all the maintenance. Precheck is invaluable. I overhauled the transmission twice, the rear end once. When I got out of that field of work and sold it, it ran great. So we'll see how it goes. I look foward to the challenge, it will be both fun and rewarding. As far as finances go, don't worry I have that covered. By the way, I planned for insurance to be around $1200-$1500 per month. My refrigeration insurance in 92 was $400 a month with a required $5 million dollar bond required for the work I was doing. It's part of the operating costs.