I have a 73 F350 which ive been trying to decide between building a 390 FE engine and a 7.3 IDI for.

A friend of mine has 3 7.3 IDI's sitting in his garage I know he would let go for cheap to me and I am wondering what would be some things I could do to get some more power out of these.

He has 2 apart engines and a complete one. Im thinking I could build the one short block up according to him is the best condition block out of them.

His father was building the engine before he passed and theyve been sitting for over a decade at this point.

I dont know much about diesel engines. I would assume you could put some higher compression pistons to bump up the power and put a cam into it.

Assuming thats what you do on these what pistons are good and what cam would be good for it. I do not know the bore dia.

I would like to put a turbo system on it as well if that changes anything and possibly with an intercooler if I can figure out how to fit that in the grill of my 50 year old truck.

I am open to pretty much any power modifications for the 7.3 however I need it to be reliable.

Roughly how much power could I make a 7.3 IDI make reliably as well using stock crank and rods?

I also plan to put one of the other IDI's he has into my 76 F250 which has a tow truck bed on it.

 

the 7.3 non turbo IDI is 21.5 to 1 compression already, i dont think they make higher compression pistons.
the best power upgrade for a 7.3 IDI is a turbo.

 

I see, is there anything else you can do to get more power out of an IDI on top of the turbo?

I know you can turn up the lift or injection pump is there something on top of that I could do?

 

Mitsubishi TE06H/banks turbo blanket + 24"x12" core FMIC installation w/ats hat & 9th gen truck

the installation of the 2nd generation banks turbo sidewinder kit (w/instructions & detailed pics)

 

There was an aftermarket cam made for 7.3l IDIs. I don't know if it is available now.

https://www.ford-trucks.com/forums/9...-cam-typ4.html

There were also headers available for the 7.3l IDI. I'm not sure how you would find them now and I think running headers eliminates the ability to use a turbo.

https://www.oilburners.net/threads/7...headers.63504/

Don't just turn up the fuel delivery screw on your injection pump so your truck billows black smoke. The IP needs to be set for your engine and whether or not it has a turbo.

Here are the suppliers that can help you build HP with a 7.3l IDI.

https://idiperformance.com/

https://moosediesel.com/

https://classicdieseldesigns.com/

 

Installing a turbo requires turning up the injector pump.
turning up the pump alone doesn't really do much except burn more fuel and draw unwanted attention to you due to black smoke out of the exhaust.

 

Thanks, ill check out your threads there!

I see, I would have to contact that oilburners people and see if they still sell them.

Im not sure if I would want headers on my diesel theyre loud enough as they are.

I know some guys who turn those injection pumps all the way up just to roll coal I think its so dumb. Especially where i live in California so diesel is around 5$ a gallon at the moment.

I will make sure to give those companies a call for information about building up one of these IDI's thanks.

I want to get the most power and economy out of these things personally.

 

If you get a pyrometer you can adjust your IP this way.

https://www.oilburners.net/threads/h...n-turbo.44479/

 

I assume it would be tuned the same way with a turbo?

Is a pyrometer a egt gauge?

 

Yes, rotate the allen screw clockwise to turn up the fuel (on an NA & turbo truck). Only rotate it 1 flat; or 60*, at a time. Correct, a pyrometer is an Exhaust Gas Temperature gauge.

My Bullnose truck is NA and I installed a pyrometer.



I've since added a vacuum gauge above the coolant temperature sensor. We'll see if I ever install a turbo.

Here's the pyrometer I installed. Interestingly, it wasn't listed on the Summit Racing website. That's where I bought it from a few years ago.

https://www.autometer.com/2-e-g-t-ki...-z-series.html

Here's another highly rated supplier of automotive gauges. I bought a Glow Shift fuel pressure gauge that I just keep in my tune up bag with my timing light and piezoelectric timing adapter.

https://www.glowshiftdirect.com/

 

What temperature should I keep it below and is turning it up going to cause it to run hotter or cooler?

I know on gassers the richer they are the cooler it will tend to run but I dont have much experience with diesels.

What do you use a vacuum gauge for on a diesel I thought only gassers had vacuum and the diesels had electric vaccum pumps?

Thanks, Ill take a look at those pyrometers!

 

exhaust temps should be kept below 1100 degrees.
over 1200 degrees will start to melt the aluminum pistons causing irreversable engine damage.
too much fuel in a diesel will create excessive heat in the cylinders causing piston melting among other things.

 

^^^THIS^^^

I added a vacuum gauge because I went through a few vacuum pumps pretty quickly. I actually think a failed vacuum pump is one reason the C6 in my Bullnose truck failed. That and the fact that my truck has 140k+ miles.

The 6.9l & 7.3l IDIs have a belt operated vacuum pump below the alternator on the passenger's side. Vacuum is used to power the power booster (unless you have hydro boost brakes) and used in a metered vacuum orifice (VRV) on the C6 trucks.

 

a diese actually DOES produce some vacuum. that is how i knew my exhaust manifold to turbo up pipes were bad, i went from showing boost on the gauge at light throttle to showing vacuum.
the reason for the vacuum pump is a non turbo diesel only produces very low vacuum, like 2-3 inches. and power brakes need at least 17-19 inches ot work properly.

 

Just keep in mind, adding fuel to an N/A IP will only add power if the pump is worn out and you're compensating for the worn pump. Even then, don't expect much. 5hp maybe? If lucky. For real power gains with the IDI, you have to start with a turbo, preferably intercooled and preferably at least turbo spec IP with it. Then you'll feel like your driving a "modern enough" truck, with more than enough power to get the job done, without crawling up hills. If you keep it N/A, you'll never get performance from it. You'll always be crawling up hill when loaded or towing. The trick to driving N/A is downshift early, hold it to the floor and give it as much show pre-hill as you can and let it rev against the governor, but even then, depending on the grade, you'll probably be making more noise than speed haha.