From what I have read I guess it's not safe to run more than 8psi boost on the 7.3 idi motoslrs. Even the ones with factory turbo. How do these guys put aftermarket turbos like the banks sidewinder and hypermax kits on their trucks and get a lot of boost? Or am I missing something? My truck had a stock turbo and a upgraded down pipe and it has a 3 inch to a 4 inch exhaust and it's half as loud as these other idi trucks I see on YouTube. I'm just curious to learn about this

 

You need to turn up the fuel to get more boost, especially if you don't have a waste gate.

 

and if you do have a wastegate then you need to adjust that.you can run 10-12 lbs without worry.past that you really should consider head studs.though,if you have it in tune,you don't need more imo.plenty of power to get in trouble with.

moosepump.com for "tweaked" injector pumps.

 

494,000 miles with most of them put on at over 14 lbs boost and still running fine. keeping your exhaust temps down is way more important than keeping the boost down. there are a few guys here that used to regularly run their engines at 4,000 rpm and 20+ psi boost and never had any issues.

 

The turbo on mine has a waste gate and it's blocked off. I did not do that it was like that when I got the truck. Iv only owned it for a month. Is that bad? Also the fuel is turned up a little. The guy I got truck from told me that the owner before him turned it up but he doesn't know how much. I don't have a gauge either I really want to get one though i feel its important.

 

What do you mean the waste gate is blocked off? You should be making a lot more than 8 pounds with a blocked wastegate.

 

The hose going to the waste gate is removed and has a nail in it. I don't know what I'm making for boost I don't have a gauge yet. The 8 pounds I was referring to was just something I read saying that more was harmful

 

first thing i would do is put a pyrometer in the truck.
then once you know what the exhaust temps are doing, you can adjust the fuel.

i turn fuel up until i see a faint hint of black smoke at full throttle, then back off a little for clean full throttle exhaust.

 

What I notice now is if I give it a little Rev on the throttle it puffs a tiny tiny bit but nothing crazy. And if I'm driving and really get on it, it sometimes gives an extremely low amount of smoke like barely any at all and even then it doesn't do it every time. If I look in mirror behind me to check if it did, and of it did leave smoke I struggle to see it it's so low. With a gauge I hear that anything below 1500 degrees is safe is that true? And even then if I run at almost that temp what is the benefit of power having it high vs of i have it just as u explained in your last reply?

 

sounds like you are properly fueled. max exhaust temp is much lower. i keep it below 1100 degrees. you will start to melt the pistons if you get over 12-1300 degrees.
my average exhaust temps are 600-700 degrees, i will hit 900-1000 on a long uphill pull with a heavy load. once i hit 900-1000 i have to downshift and get out of the throttle to lower temps.

 

So I guess my first step is to get the gauge and go from there. But about 1100 degrees is max before melting pistons?

 

A closed wqstegate is what you want as long as you aren't overboosting...and overboosting is not exactly easy with an idi.

Aluminum melting point is ~1250* F...but it'll take much more than that in the form of exhaust gas temp (which is nowhere close to accurate representation of piston temp) to melt a piston. Temp spikes of 1800-2000 won't melt a piston as long as it isn't sustained. The problem with idis is the lack of boost to cool the pistons, 1800 @ 50 psi is a lot different than 1800@20 psi. Nonetheless, it's not easy to melt a piston.

 

true this. as long as you keep the exhaust temps below 1100 though, you will not have to worry about anything.

 

Yea, absolutely worry free but there's a lot of power left on the table if kept at those Temps. Nothin wrong with keepin it safe for the sake of never having to worry regardless of the scenario.

Unloaded, there's not much to worry about unless you're doing time trials akin to pikes peak hill climbs.