For those of you who followed my 6.9 build, I posted a few things on the progress. I did my first trailer pull with it yesterday. It went very well, I hauled a car on my 20' bumper pull car trailer. The total weight was approximately 7k lbs. I encountered a few long grades on the 40 mile trip that would have brought it to its knees with the old engine. With very little throttle and about 6-7 psi boost it sailed to the top with ease. The off idle torque is strong, got the load moving easily even starting on a grade. I still have a few things to do to get it really dialed in, overall very happy with it.

 

cool - it's nice to be rewarded with a job well done with every turn of the key ..

building any engine especially a tight tolerance diesel requires great attention to detail and great planning an execution .. not to mention the expensive parts - glad it all worked out and that it's running like a champ .

 

Most definitely couldn't be happier with it, actually it has exceeded my expectations. I still have a few things to straighten out, the crossover pipe needs to be replaced it has a couple rust holes in it; costing me some boost. I'd like to ditch the muffler and tweak the fuel and possibly the wastegate just a little more. I would dare say it pulls just a bit harder than my 97 PSD.

 

Yes that is good to hear! What truck is this? Year, etc. I didn't see any diesels in your profile.

Or a link to your build topic.

 

Sorry haven't had much time or opportunity to update my profile. It's an 84 F250 RC LB 4wd, has the 6.9L/C6/BW1345 combo with D70U rear and D60 front; 4.10 gears. It's been my work truck for almost 10 years now, it's used as a tow rig and a plow truck; recently it's become somewhat of a toy as well. Over the years pretty much every drivetrain component has been completely rebuilt, most recently was the engine. The worn out 6.9 was completely torn down and given the full machine shop treatment. The heads are completely rebuilt, new valves, guides, seats, springs, seals, the whole shootin match. The the block was bored .020" over, new cam bearings, freeze plugs, new pistons, the crankshaft was polished and checked, rebuilt oil cooler, rebuilt IP, new injectors, R&D performance stage one camshaft, and a Banks Sidewinder turbo. Of course working full time and having other things going on, it took the better part of a year to get it going. It was a lot of time, money, and work; but the end result proved to be worth it. The next stage for this truck is a cab swap, the Michigan winter has taken its toll on the body. I swapped a flatbed onto the truck shortly after I got it. I really like the truck and have absolutely no interest in parting with it, might as well keep a good thing going. Something about having a simple heavy duty truck with a mechanical diesel engine brings peace of mind.

 

Sorry this is so long.

Thanks for adding that information about your truck! I'm familiar with N. Michigan, WI, and MN weather. I grew up with snow and ice and salt on the roads, learned how to drive in it, handle spin outs, etc. practicing on ice skating rinks at night when I was about 12-13 in my older friends' hot rods. We pretended like we were professional stock car drivers on the track. Since then I've driven through some horrible blizzards and at night when no one in their right mind would even attempt to drive through.

The work you did in that amount of time is impressive! I'm in no condition to do that much work anymore. If I had a fully equipped shop space AND THE MONEY I could probably do it but fortunately I don't need to.

I was interested because I have a 6.9L C6 and I will be towing up to 15K CGVW 3500 to 7500 lb. bumper pull and 5th wheel trailers, sometimes over mountain ranges. My truck is factory rated for 14K CGVW and runs very very well. I can hardly wait to get out there and in the mountains with a 4,000 lb. trailer for my first run (600 miles round trip) to see how it does. I'm very confident in this truck. I have been babying the truck until I get everything I want to get fixed finished, then I'll test it with a work load.

Yeah, for me there is almost something mystical about these Ford IDIs. They seem to me like the real diesel pick-up including the appearance. I'm convinced that the 6.9L is the best diesel engine that Ford ever used, in terms of durability and longevity and the 1987 is the best model year for the 6.9L. (Upgraded with roller rockers, solid state controller etc.) but yours matches that and then some! I did read a few of your previous topics on that truck.

The 7.3L version removed fully 1/5th of the cylinder wall thickness (If I remember correctly, from 0.25 in. down to 0.19xx in.) making it more susceptible to vibration, ie: cylinder expansion/contraction and thus more susceptible to cavitation pitting, (probably more-so with a turbo-charger). I think that significant cavitation pitting in the 7.3L is more common than people who own them on this forum are willing to acknowledge. Especially with a truck that's nearly 30 years old and had numerous previous owners. Ford recognised that this was an issue and it appears that the 7.3L IDI really opened their eyes to it but it was a bit too late for some owners. From what I've read they didn't print anything in the owner's manuals about the need for 'anti-cavitation additives' until 2 or 3 years after the production of the 7.3L IDIs had ended. If people didn't use the specified Motorcraft Coolant listed in the owner's manual, what could happen?

I just think that the 6.9L is more durable and will last longer. It was extremely well engineered specifically as a strong 6.9L non-turbo diesel, right down to the engineering calculations and design for the strength of the engine block webbing*.

Boring it out and introducing it as a 7.3L and adding the turbocharger, no doubt sacrificed some of that original strength and durability. (you can consider that an 'opinion'). Increasing performance almost always tends to be a compromise against durability and longevity which for me are the two most important things for my truck.

*IDIoit has a performance built engine block with cracked webbing now. That could be a result of less relative strength in the bored out 7.3L version and further sacrificing the durability and strength for more performance alterations. I did read that the engine block webbing was specifically designed for strength for the 6.9L non-turbo engine. That is different than a 7.3L with thinner cylinder walls (more expansion contraction), a turbocharger, and not to mention installing after-market performance cams and modified injection pumps, etc.

Personally, I don't care about added speed and acceleration, or more power by adding a Turbo Charger, that's just something extra that needs to be set up, monitored and maintained and I'm in no condition to be adding more work, more concerns and expenses like that to my truck. It runs GREAT and the Banks Power Pack set up (simply a special air cleaner and larger exhaust, mainly) does put more air through the combustion chambers and increases efficiency and performance to some extent. The next year Gale Banks was building turbo chargers for these engines so this 'Power Pack' idea although it did provide some improvements was no comparison to a turbocharger so the Idea was abandoned and forgotten.

All that being said, I found a couple of videos on Youtube about 2 years ago. The videos are probably about 8 yrs old by now. A guy in Eastern Washington with a 1986 6.9L F250 (might be a 4x4) hauling two different loads. One trip was with a load of hardwood firewood on a gooseneck trailer with a combined gross vehicle weight at the scale of about 34,000, lbs. He pulled up a long grade with that load! He wasn't going fast and was blowing black smoke going up the hill but that impressed the heck out of me! The other load was a big old bulldozer on a trailer and the combined GVW was about 26k to 28k as I recall - on a flat highway running nicely at about 55mph.

After reviewing one of the videos he mentioned that he had a 4 speed with a Gear Venders Overdrive. I don't remember the differential/ gearing BUT STILL, I was very impressed and I knew then that my truck was going to handle anything that I'll ever hitch up behind it.

I've learned that the C6 is a very strong transmission for pulling, not great on fuel economy but when it's doing hard work it's worth it.

Thanks for the additional information on your truck build

 

Absolutely no doubt on how tough these engines really are. I worked mine like a dog for seven years before the engine took its last breath, before that it had the hard life of being a farm truck. For three years this truck was used hard in commercial snow plowing, then all summer long pulling my Bronco to various wheeling spots. Everywhere I went, foot to the floor dragging something behind it. Honestly if it weren't for the blown head gasket, I would probably still dumping oil in it once a week and beating the crap out of it as I did for years. I probably could have done a cheap patch job on the engine and continued to run it, that's just not how I operate. Rather, I took it as an opportunity to finally make the truck what I always wanted it to be. I've dealt with a lot of peer pressure to "just put a Cummins in it) typical stubborn me out to prove people wrong, took the old 6.9 to the next level. I'm not one to blend in with the masses, it's cool and fun to have something that stands out from the crowd. It wouldn't be what it is today without the help of my fellow IDI fans from FTE.