Hello! Iam new to diesels and wondering if i can get some insite on the truck i just bought. Its my first diesel. Anyways its a 92 7.3 IDI with an ATS Turbo on it. I feel like the truck isn't getting the boost it should. Wondering how you increase the amount of psi also heard something about messing with the fuel pump. Any help would be great thank you!

 

Read some of the threads on this issue .. do a serch ... you will find awnswers ..

 

I'm sure people a lot smarter than i will reply to this. There are a lot of threads on just this topic. In short, there's a couple things you need be aware of before increasing boost or fuel. the 7.3 (and 6.9) have very high compression (21.5:1) so increasing boost much over 10 psi or so will run the risk of blowing head gaskets. Do some research on this before messing with increasing boost. A useful mod is to install head studs, this will hold the heads down better with higher boost pressures. Increasing fuel is also tricky, too much fuel and your EGT's will hit the roof fast. I think the max your engine can endure is 1250. I try to stay below 1000 under heavy loads. I would highly recommend getting a pyrometer before adjusting fuel delivery, if you don't have one already.

 

Do you know how much boost you are getting now? If not I would get a gauge before adding more. I think the waste gated turbos are preset to something like 7psi. I have adjusted mine to allow 12psi. There is no point going higher without an intercooler as the air is getting too hot and may actually hinder performance.

 

Thank you for the replies. So would those head studs allow me to increase the boost even more? i know you cant run the trucks higher than 12-15 psi. I have a pyrometer installed and the highest its ever gotten is 500 F. I don't have a boost gauge installed but the previous owner had the turbo professionally installed and never messed with it so iam guessing its running at 7 psi.

 

Head studs are always good to have, but you should be able to run that kind of boost without them. Some people run much more but that seems to be asking for trouble. You should grab yourself a cheap boost gauge, any kind of reading is better than guessing. They can usually be had at an auto parts store for around $30.

Where is the probe for your pyrometer mounted, maxing out at 500* seems pretty low.

 

My truck isn't gonna be used to tow anything heavier than are 3000 lb boat. Thats why iam curious if i could go higher than 12-15 psi. I got a friend with a 6.0 that's pushin 70 psi it blows my mind haha. I know the 7.3 IDI could never get to that but is 7-10 more psi gonna be noticeable at all? I bought one but it required cutting the vacuum hose in half and putting the t fitting inside, didn't want to f it up. Ill try again though. Ill look into where the probe is as well

 

The newer motors run much lower compression allowing them to push higher boost numers as there is more room in the cylinders. These IDI's have really high compression about 22.5:1 versus newer trucks that run around 16:1 or 18:1. Unless you have an intercooler, there is no point in going past 12psi. At that point the air is getting so hot that it wont help you any. The boost gauge should not "T" into a vacumn line, these trucks make no vacumn, only what the belt driven vacumn pump supplies. Your gauge should come with a hard plastic line that needs to be threaded into a port on your intake hat. I suppose you could use a rubber line and some clamps as the boost isn't to high. That is the only place you will be able to measure boost. I assume your setup is similar to this, the black hose in the middle of the intake hat is the boost line.

 

my setup looks different than yours the rubber hose going to the waste gate is what i thought you put the t fitting in but iam guessing its that white rope type material hose?

 

Boost does not = More power ... "Boost is a sign of restriction on the intake sude of the manifold to the engine....

by over boosting these idi's you can do manny things, like melt a prechamber, melt a piston, pop a HG, all just by over doing it by just 2-3 psi ...

there are cams that do help bleed some compression pressure and therfore you can run a bit more turbo pressure in the intake but in all .... its not going to be a PSD, or a 12V ..

You could lower the comp buy installing low CR pistons and then build around that ... but stock your limited my flow, both in and out, and the design just wont make 300hp with out some real $$$$$ invested... better off swapping a ve or P-pump 12V Cummins if your wanting a tire burner ..

I have a N/A engine and I regularly beat PSD 7.3's getting on the freeway .. 35's, 3.55's and a 4 spd..

its all about how efficent you can make the air go in and out .. its nothing more tha a V8 air compressor that feed on fuel ...