6.9 & 7.3 IDI Commandment Lists - IDI Do’s and Don’ts

stick_witch

Full Access Member
Joined
Aug 23, 2020
Posts
151
Reaction score
89
Location
Homer, Alaska
I have to wonder why you say this? What is the difference between loaded and empty? Is it ok if you put a turbo on your N/A engine? Is it ok to do this with a Factory Turbo engine?
Mostly just bad experience... I have had buddies who have gone to do something like try and pass people on the highway with their stock, worn out, NA idi’s (stupid idea in the first place), then maxed out their rpms and then promptly either threw a push rod, dropped a valve, or threw a connecting rod.

By loaded i just mean like under load, like as in driving, but I guess it doesn’t matter too much really. Minor detail.

I mean, these engines will hold up just fine running into the 3ks when they’re in good shape, gone through and rebuilt, or better yet rebuilt specifically with better components with boost and more power in mind.

But, most idis on the roads these days are old, neglected work trucks that’ll still run and do work for forever, despite a handful of “invisible” issues/wear and tear (which is what makes them so great), but as soon as you push them you’ll do it in, so thats kinda what I meant. Don’t push it unless you’ve gone through your motor and/or have confidence in it. These are burly, dirty beasts, they aren’t really meant to run at super high rpm and speed, they’re all about the low end grunt. So really my point is that theres just no reason for it, thats what gears are for, and if you’re maxed out on gears or can’t hang onto one than like I said in Do #10, learn to enjoy going slower than everyone else :). Idi’s are slow, thats just the nature of the beast, better to just accept it, or go out and get your motor rebuilt with better components and a turbo to handle that kind of use better. But, stock with 150,000 miles of neglect and wear and tear I have not had a positive experience running these to the limiter, and at the same time I’ve never seen a reason to do so besides to go faster or keep a unnecessarily high gear, and my answer to that is just go slower, and if you want to go faster either get a newer truck or bite the bullet and build a fresh idi with upgraded connecting rods, valve train, cam, head studs, low compression pistons, sleeved, with a girdle, turbo, cranked pump, the whole entire works, because thats what it takes[emoji23]

Sent from my iPhone using Tapatalk
 
Last edited:

stick_witch

Full Access Member
Joined
Aug 23, 2020
Posts
151
Reaction score
89
Location
Homer, Alaska
I was wondering the same. I would say most of the guys that tow heavy with them run 'em against the rev limiter going up hill, so it can't be that bad for them as long as they don't get too hot.


Rock
If you’re having to run your idi at 3300+rpm IMO you’re either trying to go way too fast or you’re towing something absolutely gigantic somewhere you shouldn’t be towing it with that truck... Sure, you can do it, but why? You should be able to pull most things most places just fine at 3400 or under. These aren’t freeway charging machines, pull to the right lane or the shoulder and crawl up the grades in second like all the other slow moving, big rigs. Pulling in 3rd just isn’t always possible.

Im not saying you can’t do it, I’m just saying you shouldn’t. From my experience, over revving has killed a few idi’s that I know of, and just diesels in general, mostly with regards to the valve train, and some from thrown connecting rods. Again, totally different story if you’re running a beefed up, boosted idi that is basically a fresh motor purpose built to run a turbo and take more abuse and produce more power. On something like that you could probably even adjust the governor screw on the db2 up to about 3600 and then you’re golden and you can probably run 3400 all day long. Heard of guys doing that quite a bit.


Sent from my iPhone using Tapatalk
 
Last edited:

Forum statistics

Threads
91,294
Posts
1,129,863
Members
24,107
Latest member
lewisstevey7

Members online

Top