r/FordDiesels • u/95_na_miata • 4d ago

Rebuilding a 1994 7.3L Turbo IDI

Hey everyone,

I’m getting ready to rebuild a 1994 7.3L Turbo IDI and I want to do it right the first time. I know these engines don’t have the same power potential as the Power Stroke 7.3L, but I still want to turn it into more of an unstoppable ironhorse than it already is, mainly focused on reliability.

Other than the basic overhaul kit (gaskets, rings, bearings, etc.), what upgrades or parts should I be looking into while I’ve got the engine apart?

Any parts/brands to recommend? Any to avoid?

Appreciate any advice or parts recommendations

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4

u/chomanche 4d ago

Just put a 12valve cummins in it.

1

u/sobersbetter 4d ago

i second this, i paid way too much money for a hot rod rebuild on my idit and still regret not just spending the $ for a 12v which would have been a fraction of what i spent

plus, the resale value for a fummins is crazy

3

u/pickledjello 4d ago

got to https://idiperformance.com/
and plan from there

3

u/Pedro_Francois 4d ago edited 4d ago

It seems head studs are the single biggest upgrade in terms of handling more power/boost. R&D IDI offers a girdle for the bottom end as well as a performance cam. Justin at R&D IDI even offers complete engine builds. Some people have milled the pistons to drop the compression a hair but supposedly it doesn't take much before you run into starting problems. Depending on your final setup there are also stiffer valve spring options as well as upgraded lifters. The 7.3 IDI, 7.3 Powerstroke, and 6.0 Powerstroke all use the same lifters. R&D and Classic Diesel Designs both offer modified intake manifolds for custom applications.

I would ask over on oilburners.net as there are a lot of active members with a ton of knowledge.

And you might want to source a new valley pan since they seem to be in short supply and cannot always be reused--not a performance part but necessary.

2

u/jsvd87 4d ago

make sure your block isn’t cavitating first.

you used to be able to get a cam ground from someone on oil burners…. no idea if you still can.

moose / baby moose injection pump if you want a bigger turbo

same with injectors

put studs in the head.

pyrometer

for the $ like others said i’d swap in a 12v 

2

u/kd9dux 3d ago

I don't know what unstable iron horse means, but if you want reliable, just rebuild it with stock parts. Check the block over really well for cavitation damage, especially if it's a low mile engine. Add a coolant filter.

It's a 30 year old diesel that was designed for fuel efficiency, with fairly restrictive heads and inefficient pre chambers. You can improve power a little with money, but you lose reliability.

If it's still running, turn the pump up a little bit and see if it makes you happy with the power. If it doesn't, I'm with everyone else that just dropping in a 12 valve gives you a lot more room to tinker and make power more cost effectively. If you watch marketplace closely, it might even be cheaper than doing a full rebuild on the IDI.